Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/27/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
817 PM MST MON JAN 26 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO AFFECT THE REGION TONIGHT
WITH PERIODS OF LIGHT RAIN. THIS DISTURBANCE WILL MOVE NORTH OF THE
REGION TUESDAY...AND IN ITS WAKE ABOVE NORMAL TEMPERATURES AND
HIGHER THAN NORMAL HUMIDITIES WILL PREVAIL. ANOTHER LOW PRESSURE
SYSTEM WILL BRING ADDITIONAL MOISTURE AND RENEWED HIGHER CHANCES FOR
PRECIPITATION LATE IN THE WEEK AND INTO THE WEEKEND.
&&
.DISCUSSION...
RAINFALL HAS LARGELY ENDED ACROSS SOUTHEAST CALIFORNIA AND FAR
SOUTHWEST ARIZONA AS LOW PRESSURE CONTINUES TO ROTATE THROUGH THE
AREA THIS EVENING. A BAND OF PRECIPITATION WAS LOCATED FROM LAS
VEGAS TO PHOENIX TO NOGALES BUT THUS FAR RAINFALL HAS BEEN VERY
LIGHT ACROSS THE AREA. SOME SPOTS IN THE PHOENIX METRO ARE JUST NOW
/03Z/ SEEING THEIR FIRST DROPS OF RAIN AS DEWPOINTS HAVE HELD STEADY
IN THE UPPER 20S TO LOWER 30S ALL EVENING. FINALLY STARTING TO SEE
DEWPOINT DEPRESSIONS DECREASE AFTER A COUPLE HOURS OF VIRGA ACROSS
THE METRO.
MODELS CONTINUE TO PUSH THE LOW OUT OF THE AREA RAPIDLY OVERNIGHT.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA ARE PRETTY MUCH DONE WITH
RAIN FOR THE NIGHT ASIDE FROM A FEW WIDELY SCATTERED SHOWERS.
HOWEVER THE HRRR SEEMS TO HAVE A DECENT DEPICTION OF THE CURRENT
WEATHER AND BRINGS ON LAST AREA OF RAINFALL INTO THE AREA BETWEEN
06Z-09Z. THIS APPEARS TO BE EVIDENT ON RADAR NEAR NOGALES ALTHOUGH
IT WILL STILL BE SEVERAL MORE HOURS BEFORE ANY OF THIS RAINFALL
MAKES INTO THE LOWER AZ DESERTS. THE INHERITED FORECAST DRIES OUT
CONDITIONS ACROSS THE WESTERN FORECAST AREA WHEREAS 30-50 POPS ARE
RETAINED FOR THE REST OF THE OVERNIGHT HOURS. THIS MATCHES WELL WITH
INCOMING 00Z MODEL DATA AND NO CHANGES APPEAR TO BE NECESSARY AT
THIS POINT. JUST MADE SOME MINOR REVISIONS TO TEMPS AND DEWPOINTS
BASED ON OBSERVATIONAL TRENDS SO FAR...OTHERWISE NO SIGNIFICANT
CHANGES NECESSARY.
&&
.PREVIOUS DISCUSSION...
DRIER AIR ALOFT WILL SURGE INTO THE FORECAST AREA TUESDAY...BUT
RESIDUAL LOW LEVEL MOISTURE WILL KEEP SOME LINGERING STRATO-CU
THROUGH AT LEAST THE EARLY AFTERNOON. HOWEVER...THERE SHOULD BE
SUFFICIENT CLOUD BREAKS DURING PEAK HEATING ALONG WITH ABNORMALLY
WARM H8 TEMPERATURES TO RESULT IN AFTERNOON HIGHS ABOVE 3F-6F ABOVE
NORMAL. SHORTWAVE RIDGING...WARM TEMPERATURES ALOFT AND NEARLY FULL
INSOLATION WILL PREVAIL THROUGH WEDNESDAY PROVIDING ANOTHER
UNUSUALLY WARM DAY WITH HIGHS SOME 5F-10F ABOVE NORMAL.
ANOTHER UPPER LOW EMANATING FROM THE EAST PACIFIC WILL MOVE INTO THE
REGION WEDNESDAY NIGHT...INITIALLY AS AN OPEN WAVE HOWEVER TAPPING A
WEALTH OF SUBTROPICAL MOISTURE WITH A DEEP FETCH OF MERIDIONAL FLOW.
WHILE THE MAGNITUDE OF SUBTROPICAL MOISTURE REMAINS IN
QUESTION...SUBJECTIVE PATTERN RECOGNITION AND MODEL TRENDS SUPPORT A
MORE SIGNIFICANT SURGE THAN PREVIOUSLY FORECAST BY GLOBAL MODELS.
FOR NOW...BEST RAINFALL CHANCES WERE HEDGED ACROSS CENTRAL AND
EASTERN ARIZONA. EXACT TIMING OF THE RAIN IS HARD TO NAIL DOWN AT
THIS POINT...BUT FEEL BEST CHANCES WILL BE DURING THE DAYTIME HOURS
FRIDAY. WOULD NOT BE SURPRISED IF LINGERING SHOWERS PERSIST THROUGH
MUCH OF SATURDAY AS THE UPPER LOW COULD BECOME QUASI-STATIONARY OVER
THE REGION FOR A DAY OR SO. HAVE SELECTIVELY DECREASED HIGHS BY A
FEW DEGREES ON FRIDAY GIVEN THE HIGHER CONFIDENCE OF RAIN AND
MAINTAINED A NEAR PERSISTENCE FORECAST FOR SATURDAY.
CONFIDENCE FOR THIS COMING WEEKEND IS STILL FAIRLY LOW AS MODELS
HAVE HAD SOME DIFFICULTY OVER THE PAST FEW MODEL RUNS...BUT IN
GENERAL IT WOULD SEEM THINGS MAY DRY OUT BY SATURDAY NIGHT OR EARLY
SUNDAY. SLIGHT CHANCE POPS REMAIN IN THE FORECAST INTO SATURDAY
NIGHT...BUT HAVE TRIMMED POPS ON SUNDAY WITH THE ONLY SLIGHT CHANCE
POPS NOW OVER THE HIGHER TERRAIN EAST OF PHOENIX.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
SHOWERS FINALLY STARTING TO FILL IN ACROSS THE AREA THIS EVENING AS
OF 03Z ALTHOUGH AMOUNTS HAVE BEEN LIGHT AND UPSTREAM AVIATION
IMPACTS APPEAR TO BE MINIMAL. THINKING THERE IS A GOOD CHANCE
CEILINGS WILL DROP TO 7-8KFT OVERNIGHT COINCIDENT WITH THE ONSET OF
THE RAIN BUT WIDESPREAD VSBY REDUCTIONS LOOK MINIMAL. PRECIP SHOULD
END AFTER 09Z WITH IMPROVING CONDITIONS AFTERWARD. GRADUAL CLEARING
EXPECTED THROUGH THE DAY TUESDAY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SHOWERS STARTING TO TAPER OFF AS OF 03Z BUT WILL CONTINUE TO MONITOR
CEILINGS. CEILINGS SHOULD GRADUALLY RISE TO AROUND 5-6KFT OVERNIGHT.
AS FOR FOR...ITS A TOUGH CALL AS IR IMAGERY STILL SUGGESTS QUITE A
BIT OF CLOUD COVER WILL HAVE TO MOVE THROUGH THE AREA BEFORE SKIES
CLEAR ENTIRELY. MAY INTRODUCE A 3-5SM PERIOD BEFORE 12Z TO SUGGEST
THE PRESENCE OF HAZE BUT WILL HOLD SHORT OF MENTIONING ANYTHING IFR
OR LOWER.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
ABOVE NORMAL TEMPERATURES AND RELATIVELY MOIST CONDITIONS WILL
PREVAIL WEDNESDAY-THURSDAY AS A RIDGE PREDOMINATES ACROSS MEXICO.
ANOTHER LOW PRESSURE SYSTEM WILL RESULT IN INCREASING RAIN CHANCES
AND COOLER TEMPERATURES FRIDAY AND SATURDAY. A WARMING AND DRYING
TREND IS EXPECTED SUNDAY AS A RIDGE BUILDS ACROSS CALIFORNIA.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...LEINS/MO/KUHLMAN
AVIATION...LEINS
FIRE WEATHER...HIRSCH
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
440 PM MST MON JAN 26 2015
.UPDATE...UPDATED AVIATION DISCUSSION...
&&
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO AFFECT THE REGION TONIGHT
WITH PERIODS OF LIGHT RAIN. THIS DISTURBANCE WILL MOVE NORTH OF THE
REGION TUESDAY...AND IN ITS WAKE ABOVE NORMAL TEMPERATURES AND
HIGHER THAN NORMAL HUMIDITIES WILL PREVAIL. ANOTHER LOW PRESSURE
SYSTEM WILL BRING ADDITIONAL MOISTURE AND RENEWED HIGHER CHANCES FOR
PRECIPITATION LATE IN THE WEEK AND INTO THE WEEKEND.
&&
.DISCUSSION...
A WEAKENING PV ANOMALY NEAR 31N 118W WAS LIFTING NORTH ON THE
LEEWARD SIDE OF A HIGH AMPLITUDE RIDGE DOMINATING THE WRN CONUS THIS
AFTERNOON. ASCENT IN THE FORM A BROAD ISENTROPIC LIFT AND WARM
ADVECTION WAS ACTING ON A PLUME OF HIGHER THETA-E AIR STRETCHING
FROM SERN ARIZONA THROUGH WEST CENTRAL ARIZONA. WITHIN THE OVERALL
FLOW PATTERN OF BACKED MIDTROPOSPHERIC WINDS...RADAR ECHOES INDICATE
A MESO-VORT NEAR KIPL WHICH APPEARS TO BE ENHANCING ECHOES LIFT
THROUGH SERN CALIFORNIA. ACROSS CNTRL ARIZONA...A DEEP LAYER OF DRY
AIR BELOW THE H7 LEVEL STILL PERSISTS WITH T/TD DEPRESSIONS NEAR 40F
SUGGESTING MORE DIFFICULTY WILL BE ENCOUNTERED REACHING WETBULB
TEMPERATURES AND ACCUMULATING RAINFALL REACHING THE SFC.
THE PREPONDERANCE OF HIGH RESOLUTION MODELS MATCH CURRENT RADAR
RETURNS QUITE CLOSELY SHOWING A SOLID CORRIDOR OF SHOWERS LIFTING
THROUGH WRN ARIZONA...DEVELOPING AREA OF BROKEN SHOWERS IN THE
VICINITY OF THE AFOREMENTIONED MESO-VORT...AND WEAKER ECHOES LIFTING
NORTH FROM THE TUCSON AREA. WHILE THE ENTIRE FORECAST AREA WILL
LIKELY SEE SOME MEASURE OF RAINFALL...PREFERRED HIGH RESOLUTION EMC
WRF AND NSSL WRF MEMBERS DEPICT THE INITIAL CNTRL ARIZONA RAIN BAND
STRUGGLING THIS AFTERNOON...AND MORE SCT FAST MOVING SHOWERS THIS
EVENING AND OVERNIGHT LIFTING INTO NRN ARIZONA.
EVENTUALLY...SUBSIDENT DOWNGLIDE AND DRYING (ALREADY SEEN IN WV
IMAGERY PROPAGATING UP THE BAJA PENINSULA WILL OVERSPREAD THE
REGION...DRASTICALLY LIMITING THE RAIN POTENTIAL.
DRIER AIR ALOFT WILL SURGE INTO THE FORECAST AREA TUESDAY...BUT
RESIDUAL LOW LEVEL MOISTURE WILL KEEP SOME LINGERING STRATO-CU
THROUGH AT LEAST THE EARLY AFTERNOON. HOWEVER...THERE SHOULD BE
SUFFICIENT CLOUD BREAKS DURING PEAK HEATING ALONG WITH ABNORMALLY
WARM H8 TEMPERATURES TO RESULT IN AFTERNOON HIGHS ABOVE 3F-6F ABOVE
NORMAL. SHORTWAVE RIDGING...WARM TEMPERATURES ALOFT AND NEARLY FULL
INSOLATION WILL PREVAIL THROUGH WEDNESDAY PROVIDING ANOTHER
UNUSUALLY WARM DAY WITH HIGHS SOME 5F-10F ABOVE NORMAL.
ANOTHER UPPER LOW EMANATING FROM THE EAST PACIFIC WILL MOVE INTO THE
REGION WEDNESDAY NIGHT...INITIALLY AS AN OPEN WAVE HOWEVER TAPPING A
WEALTH OF SUBTROPICAL MOISTURE WITH A DEEP FETCH OF MERIDIONAL FLOW.
WHILE THE MAGNITUDE OF SUBTROPICAL MOISTURE REMAINS IN
QUESTION...SUBJECTIVE PATTERN RECOGNITION AND MODEL TRENDS SUPPORT A
MORE SIGNIFICANT SURGE THAN PREVIOUSLY FORECAST BY GLOBAL MODELS.
FOR NOW...BEST RAINFALL CHANCES WERE HEDGED ACROSS CENTRAL AND
EASTERN ARIZONA. EXACT TIMING OF THE RAIN IS HARD TO NAIL DOWN AT
THIS POINT...BUT FEEL BEST CHANCES WILL BE DURING THE DAYTIME HOURS
FRIDAY. WOULD NOT BE SURPRISED IF LINGERING SHOWERS PERSIST THROUGH
MUCH OF SATURDAY AS THE UPPER LOW COULD BECOME QUASI-STATIONARY OVER
THE REGION FOR A DAY OR SO. HAVE SELECTIVELY DECREASED HIGHS BY A
FEW DEGREES ON FRIDAY GIVEN THE HIGHER CONFIDENCE OF RAIN AND
MAINTAINED A NEAR PERSISTENCE FORECAST FOR SATURDAY.
CONFIDENCE FOR THIS COMING WEEKEND IS STILL FAIRLY LOW AS MODELS
HAVE HAD SOME DIFFICULTY OVER THE PAST FEW MODEL RUNS...BUT IN
GENERAL IT WOULD SEEM THINGS MAY DRY OUT BY SATURDAY NIGHT OR EARLY
SUNDAY. SLIGHT CHANCE POPS REMAIN IN THE FORECAST INTO SATURDAY
NIGHT...BUT HAVE TRIMMED POPS ON SUNDAY WITH THE ONLY SLIGHT CHANCE
POPS NOW OVER THE HIGHER TERRAIN EAST OF PHOENIX.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
RAIN HAS BEEN SLOW TO MOVE INTO THE METRO SO FAR TODAY AND DEWPOINTS
REMAIN IN THE LOWER 30S. UNLESS THERE IS A RAPID SURGE OF MOISTURE
NORTHWARD BY EARLY EVENING...MOST OF THE ACTIVITY ON RADAR WILL BE
VIRGA OR SPRINKLES. TONED DOWN THE TAFS A BIT MAINLY TO INDICATE
VCSH AND IT APPEARS LESS AND LESS LIKELY THERE WILL BE SEVERAL HOURS
OF STEADY RAIN. HRRR BEGINNING TO LATCH ON TO THIS IDEA AS WELL. AS
FOR CIGS WITH LESS RAINFALL ACROSS THE METRO I DONT THINK CIGS WILL
GET LOWER THAN 7-8KFT OVERNIGHT. CLEARING EXPECTED BY MID MORNING
TUESDAY ACROSS THE AREA.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
RAIN ALREADY WRAPPING UP IN IMPERIAL BUT STILL LOOKING AT A FEW MORE
HOURS IN BLYTHE. OVERALL EXPECT CONDITIONS TO CONTINUE TO IMPROVE
FROM APPROX 03-06Z ONWARD AS RAIN EXITS THE AREA. THE THREAT OF
LOWERED CEILINGS IS STILL VALID AS BOTH SITES SAW RAINFALL TODAY BUT
THINKING THEY SHOULD REMAIN AT 4-5KFT OR HIGHER. NOT GOING TO
MENTION ANY FOG AT EITHER SITE AS CLOUDS SHOULD REMAIN THICK ENOUGH
TO PRECLUDE WIDESPREAD DEVELOPMENT BUT IF THINGS CLEAR OUT
RAPIDLY...MAY NEED TO INTRODUCE MVFR/IVF VSBYS TOWARD DAYBREAK.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
ABOVE NORMAL TEMPERATURES AND RELATIVELY MOIST CONDITIONS WILL
PREVAIL WEDNESDAY-THURSDAY AS A RIDGE PREDOMINATES ACROSS MEXICO.
ANOTHER LOW PRESSURE SYSTEM WILL RESULT IN INCREASING RAIN CHANCES
AND COOLER TEMPERATURES FRIDAY AND SATURDAY. A WARMING AND DRYING
TREND IS EXPECTED SUNDAY AS A RIDGE BUILDS ACROSS CALIFORNIA.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MO/KUHLMAN
AVIATION...LEINS
FIRE WEATHER...HIRSCH
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
418 PM PST MON JAN 26 2015
.SYNOPSIS...A WEAK STORM OVER SOUTHERN CALIFORNIA WILL SPREAD HIGH
CLOUDS OVER THE BAY AREA TONIGHT WITH A CHANCE OF SHOWERS FOR THE
CENTRAL COAST OVERNIGHT INTO TUESDAY MORNING. THE SYSTEM WILL MOVE
EASTWARD BY TUESDAY NIGHT WITH DRY AND MILD WEATHER FORECAST WEDNESDAY
THROUGH FRIDAY. A WARMING TREND IS FORECAST OVER THE WEEKEND AS
HIGH PRESSURE STRENGTHENS.
&&
.DISCUSSION...AS OF 2:19 PM PST MONDAY...TEMPERATURES IN THE BAY
AREA ARE TRENDING SLIGHTLY WARMER THIS AFTERNOON DUE TO LESS FOG
COVERAGE THIS MORNING. FARTHER SOUTH TEMPERATURES ALONG THE
CENTRAL COAST ARE MUCH COOLER AFTER YESTERDAYS RECORD WARMTH...AS
HIGH CLOUDS NOW BLANKET THE REGION IN ASSOCIATION WITH THE
CIRCULATION LOCATED WEST OF SAN DIEGO. RIGHT NOW SOME RAIN IS
FALLING IN THE DESERTS OF SOUTHERN CALIFORNIA WITH 29 PALMS AND
CHINA LAKE REPORTING LIGHT RAIN LAST HOUR. ITS AN UNUSUAL SET-UP
BUT ITS THE MOISTURE TO OUR SOUTH THAT WILL BE ADVECTED NORTHWARD
OVER THE NEXT 12-18 HOURS. LATEST MODELS CONTINUE TO KEEP BEST
CHANCES OF PRECIP EAST OF OUR DISTRICT BUT SOME OF THE MESO-SCALE
MODELS PAINT SOME SHOWERS OVER THE HILLS OF MONTEREY AND SAN
BENITO COUNTY AROUND SUNRISE TUESDAY AS THE SYSTEM BEGINS TO EJECT
INLAND. IN PARTICULAR THE LATEST RAP MODEL RUNS HAVE TRENDED
WETTER OVER MONTEREY/SAN BENITO COUNTY TUESDAY MORNING. HAVE LEFT
SHOWER CHANCES IN THE FORECAST TO ACCOUNT FOR THIS. ANY SHOWER
THREAT SHOULD END BY TUESDAY AFTERNOON AS THE MAIN UPPER LOW MOVES
EASTWARD.
AS THAT LOW MOVES TO OUR EAST THE SYNOPTIC PATTERN REMAINS FAIRLY
NONDESCRIPT WITH WEAK CYCLONIC FLOW ALOFT THAT MAY GENERATE SOME
SHOWERS OVER THE SIERRA BY THURSDAY BUT NO PRECIP FOR THE BAY
AREA. OUR TEMPERATURES WILL TREND SLIGHTLY ABOVE NORMAL WITH
AFTERNOON HIGHS IN THE 60S THROUGH THE WORK-WEEK.
ANOTHER WARM WEEKEND LOOKS TO BE IN STORE AS A RIDGE BUILDS
SATURDAY AND SUNDAY WITH 850 MB TEMPS TO AROUND 15 CELSIUS. DOESN`T
LOOK AS WARM AS LAST WEEKEND SO NOT EXPECTING ANY RECORDS.
THE PATTERN BEYOND SUNDAY BECOMES MORE MUDDLED. THE ECMWF AND GEM
MODEL ARE ACTUALLY TRENDING A LITTLE WETTER WHILE THE GFS REMAINS
DRY. GIVEN THE HISTORIC DRY PATTERN WERE UNDER WILL NOT BE
INTRODUCING DAY 7 POPS AT THIS TIME.
&&
.AVIATION...AS OF 4:00 PM PST MONDAY...A WEAK WEATHER SYSTEM
OFF THE SOUTHERN CALIFORNIA COAST WILL CONTINUE TO DRAW A BLANKET
OF MID AND HIGH LEVEL CLOUDS OVER THE AREA TONIGHT AND TUESDAY.
MOSTLY VFR CONDITIONS ARE EXPECTED EXCEPT LOCAL IFR CONDITIONS IN
FOG IN THE VALLEYS LATE TONIGHT AND EARLY TUESDAY. LIGHT AND
LOCALLY VARIABLE WINDS WILL PREVAIL.
VICINITY OF KSFO...VFR. LIGHT AND VARIABLE WINDS.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR. LIGHT WINDS.
&&
.MARINE...AS OF 1:49 PM PST MONDAY...EAST WINDS OVER THE COASTAL
WATERS WILL TURN TO THE SOUTHEAST LATER TODAY AND TONIGHT AS WEAK
LOW PRESSURE DEVELOPS OFFSHORE. HIGH PRESSURE WILL BUILD OFF THE
NORTHERN CALIFORNIA COAST BY MIDWEEK...RESULTING IN LIGHT TO
MODERATE NORTHWEST WINDS DURING THE SECOND HALF OF THE WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...NONE.
$$
PUBLIC FORECAST: RWW
AVIATION: CW
MARINE: DYKEMA
VISIT US AT WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1234 AM EST SUN JAN 25 2015
.SYNOPSIS...
BEHIND A DEPARTING COASTAL STORM...SOME LINGERING SNOW
SHOWERS OR PATCHY FREEZING DRIZZLE WILL OCCUR THIS EVENING. A COLD
FRONT WILL MOVE ACROSS THE REGION LATE TONIGHT WITH SOME ADDITIONAL
SNOW SHOWERS...MAINLY FOR NORTHWESTERN PARTS OF THE AREA. AN ARCTIC
AIR MASS MOVING IN BEHIND THIS FRONT WILL ALLOW FOR MUCH COLDER
TEMPERATURES ON SUNDAY. ANOTHER COASTAL STORM WITH ACCUMULATING SNOW
IS POSSIBLE DURING THE UPCOMING WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1225 AM EST...SNOW SHOWERS WERE MOVING ACROSS THE WESTERN
PORTION OF THE FA. THESE SNOW SHOWERS WILL TEND TO WEAKEN AS THEY
MOVE FARTHER EAST INTO DRIER AIR.
THE 3KM HRRR SHOWS THIS ACTIVITY WEAKENING AND DRYING UP AS IT
MOVES FURTHER EASTWARD...AND 00Z KALY SOUNDING WOULD SUGGEST DRY
AIR WOULD PROBABLY WIN OUT. STILL...WILL CONTINUE TO MONITOR AS IT
PROGRESSES FURTHER EASTWARD. WITH COLDER AIR AND DEEPENING
MOISTURE ALOFT ARRIVING AHEAD OF THE NEXT FRONTAL SYSTEM...PTYPE
WILL BE SNOW SHOWERS.
THE COLD FRONT LOCATED TO OUR NORTHWEST ACROSS THE EASTERN GREAT
LAKES ASSOCIATED WITH NORTHERN STREAM ENERGY WILL MOVE
SOUTHEASTWARD INTO THE AREA LATE TONIGHT. SCATTERED SNOW SHOWERS
WILL PRECEDE AND ACCOMPANY THE BOUNDARY AND SHORT WAVE FOR THE
ADIRONDACKS...WITH LITTLE ACTIVITY EXPECTED FURTHER SOUTH AND
EAST.
TEMPERATURES WILL DROP ONLY GRADUALLY TONIGHT AS THE COLD FRONT
APPROACHES...AND MAY WIND UP HOLDING STEADY FOR MANY LOCATIONS IN
THE MID TO UPPER 20S. FAR NORTHWESTERN AREAS MAY FALL LATE
TONIGHT INTO THE TEENS AS THE COLD FRONT PASSES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
THE PASSAGE OF THE COLD FRONT IS EXPECTED AROUND DAY BREAK ACROSS
THE NORTHWESTERN PORTION OF THE FORECAST AREA AND BEFORE MIDDAY
ACROSS THE SOUTHEAST. HIGHER PRESSURE WILL BEGIN TO BUILD IN BEHIND
THE BOUNDARY DURING THE AFTERNOON. THERE WILL BE LITTLE RECOVERY IN
TEMPERATURES SUNDAY WITH THE COLD AIR ADVECTION IN THE WAKE OF THE
BOUNDARY. IN ADDITION THE BRISK NORTHWESTERLY WINDS WILL MAKE IN
FEEL EVEN COLDER.
HIGH PRESSURE CENTERED TO OUR NORTH WILL PASS OVER THE REGION SUNDAY
NIGHT INTO MONDAY AS AN AREA OF LOW PRESSURE PASSES TO OUR SOUTH IN
ASSOCIATION WITH A VIGOROUS SHORT WAVE. THE SURFACE LOW IS THEN
EXPECTED TO MOVE OFF THE CAROLINA COAST ON MONDAY. HOWEVER ALOFT AN
UPPER LOW IS EXPECTED TO DEVELOP ALONG THE MID ATLANTIC COAST MONDAY
NIGHT AS THE SHORT WAVE ROTATES THROUGH THE BASE OF THE DEEP LONGWAVE
TROUGH OVER THE EASTERN UNITED STATES. THIS WILL RESULT IN FURTHER
DEVELOPMENT/DEEPENING OF THE SURFACE LOW OFF THE MID ATLANTIC COAST.
IT WILL BE COLD AND FAIR SUNDAY NIGHT AS THE RIDGE DOMINATES OUR
WEATHER. LOWS ARE FORECAST TO BE IN THE SINGLE DIGITS WITH BELOW
ZERO READINGS ACROSS THE NORTHWESTERN THIRD OF THE FORECAST AREA.
WINDS WILL BE LIGHT. TEMPERATURES MONDAY ARE EXPECTED TO RUN AROUND
10 DEGREES BELOW NORMAL.
AT THIS TIME IT APPEARS THE FORECAST AREA MAY BE ON THE NORTHERN
EDGE OF THE PRECIPITATION SHIELD MONDAY WITH GREATER AND MORE
WIDESPREAD CHANCES FOR SNOW MONDAY NIGHT AS THE SURFACE LOW
DEEPENS AND IS DRAWN UNDER THE UPPER LOW MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE LONG TERM PERIOD WILL START OFF ACTIVE...ALTHOUGH THE DEGREE OF
IMPACT IS STILL YET TO BE DETERMINED. IN ADDITION...RATHER COLD
WEATHER IS EXPECTED THROUGH THE ENTIRE LONG TERM PERIOD.
AS AN UPPER LEVEL DISTURBANCE DIVES OUT OF THE NORTHERN STREAM
TOWARDS THE EASTERN SEABOARD...A NEW AREA OF LOW PRESSURE WILL
DEVELOP OFF THE COAST AND RAPIDLY DEEPEN ON TUESDAY. THIS IS SHOWN
IN THE 12Z ECMWF...GGEM...GFS...NAM AND MOST MEMBERS OF THE 12Z
GEFS. THE UPPER LEVEL ENERGY WILL BECOME CUT OFF...ALLOWING FOR A
PROLONGED PERIOD OF PRECIP IN THE FORM OF SNOW TO OCCUR ACROSS MUCH
OF NEW ENGLAND. OUR REGION WILL BE ON THE WESTERN FRINGE OF THIS
SYSTEM...ALTHOUGH THE EXACT TRACK IS STILL FAR FROM CERTAIN. WHILE
SOME SNOW LOOKS TO OCCUR ON TUESDAY...AMOUNTS ARE STILL QUITE
UNCERTAIN...WITH THE BEST CHANCE ACROSS EASTERN PARTS OF THE AREA.
WHILE THE 12Z NAM/ECMWF BOTH HAD A LOT OF PRECIP OVER OUR AREA...THE
12Z GGEM/GFS AND 18Z NAM KEPT THE HEAVIER PRECIP TO OUR EAST. AT
THIS POINT...WILL FAVOR AREAS EAST OF THE HUDSON RIVER FOR THE MOST
SNOWFALL AND HIGHEST POPS FOR TUESDAY INTO TUESDAY NIGHT.
STILL...THERE IS POTENTIAL FOR THIS STORM TO TRACK CLOSER TO OUR
AREA AND BRING A SIGNIFICANT SNOWFALL TO THE ENTIRE CWA...AND THE
WITH THE UPPER LEVEL LOW BECOMING CUTOFF...THIS MAKES THE FORECAST
RATHER DIFFICULT AND PARTICULAR UNCERTAIN. WE WILL MENTION THIS
SYSTEM IN OUR HWO. TEMPS WILL CONTINUE TO BELOW NORMAL WITH AN
ARCTIC AIRMASS IN PLACE...WITH HIGHS ONLY IN THE TEENS AND 20S...AND
LOWS BETWEEN -10 AND 5.
BY WEDNESDAY...THE STORM WILL BE MOVING AWAY...BUT IT REMAIN COLD
AND BLUSTERY BEHIND THE SYSTEM. TEMPS WILL CONTINUE TO BE IN THE
TEENS AND 20S FOR WED...WITH SINGLE DIGITS FOR WED NIGHT. NO PRECIP
IS EXPECTED...WITH A PARTLY TO MOSTLY CLEAR SKY.
ANOTHER NORTHERN STREAM CLIPPER SYSTEM LOOK TO IMPACT THE REGION
SOMETIME BETWEEN THURSDAY AFTERNOON AND FRIDAY. A ROUND OF LIGHT
SNOW LOOKS TO SPREAD FROM WEST TO EAST ACROSS THE AREA...WITH SOME
ACCUMULATION POSSIBLE FOR ALL AREAS. TEMPS LOOK A LITTLE WARMER THAN
RECENT DAYS...WITH HIGHS IN THE 20S FOR THURS/FRI. OVERNIGHT LOWS ON
THURS NIGHT WILL BE IN THE MID TEENS TO MID 20S.
COLDER AIR WILL ARRIVE BEHIND THIS NORTHERN STREAM CLIPPER SYSTEM.
MIN ON FRI NIGHT WILL BE IN THE SINGLE DIGITS. IT WILL BE COLD AND
BLUSTERY FOR SATURDAY WITH A PARTLY CLOUDY SKY...AND HIGHS IN THE
TEENS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AN ARCTIC COLD FRONT WILL APPROACH FROM THE NORTHWEST TOWARD
DAYBREAK...AND PASS ACROSS THE TAF SITES SUNDAY MORNING. HIGH
PRESSURE WILL THEN BUILD ACROSS THE TAF SITES FROM THE NORTH FOR
LATER SUNDAY AND SUNDAY NIGHT.
ABUNDANT LOW LEVEL MOISTURE POOLING AHEAD OF THE INCOMING FRONT HAS
RESULTED IN AREAS OF MVFR CIGS...WITH EVEN SOME ISOLATED IFR CIGS
AT KPSF. WE EXPECT MAINLY MVFR CIGS TO PERSIST AT ALL TAF SITES
EXCEPT KPOU UNTIL THE FRONT PASSES BETWEEN 11Z-13Z/SUN.
ALSO...SOME SNOW SHOWERS/FLURRIES MAY REACH KGFL/KALB/KPSF...ESP AS
THE FRONT PASSES THROUGH. THIS COULD CREATE BRIEF REDUCTIONS OF
VSBYS INTO THE MVFR/IFR RANGE.
ONCE THE FRONT PASSES...VFR CONDITIONS ARE THEN EXPECTED THROUGH
AT LEAST 06Z/MON.
WEST WINDS WILL CONTINUE THROUGH DAYBREAK AT 5-10 KT...BUT MAY
OCCASIONALLY GUST INTO THE 15-20 KT RANGE AT KALB AND KPSF. AS THE
FRONT PASSES...WINDS WILL VEER SLIGHTLY INTO THE NORTHWEST TO
NORTH...AND INCREASE TO 10-15 KT FOR LATER SUNDAY MORNING INTO THE
AFTERNOON...WITH SOME GUSTS POSSIBLY REACHING INTO THE 20-25 KT
RANGE AT KALB AND KPSF. WINDS WILL DECREASE TO LESS THAN 8 KT
SHORTLY AFTER SUNSET.
OUTLOOK...
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SN.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SN.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDRO PROBLEMS ARE EXPECTED THROUGH EARLY NEXT WEEK.
THE PRECIPITATION THAT DOES OCCUR WILL BE IN THE FORM OF SNOW.
ICE WILL CONTINUE TO THICKEN ON RIVERS...STREAMS...CREEKS...LAKES
AND OTHER BODIES OF WATER.
THE EAGLE BRIDGE GAGE ON THE HOOSIC RIVER CONTINUES TO BE HAMPERED
BY ICE EFFECTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/11
NEAR TERM...IAA/FRUGIS/11
SHORT TERM...IAA
LONG TERM...FRUGIS
AVIATION...FRUGIS/KL
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1226 AM EST SUN JAN 25 2015
.SYNOPSIS...
BEHIND A DEPARTING COASTAL STORM...SOME LINGERING SNOW
SHOWERS OR PATCHY FREEZING DRIZZLE WILL OCCUR THIS EVENING. A COLD
FRONT WILL MOVE ACROSS THE REGION LATE TONIGHT WITH SOME ADDITIONAL
SNOW SHOWERS...MAINLY FOR NORTHWESTERN PARTS OF THE AREA. AN ARCTIC
AIR MASS MOVING IN BEHIND THIS FRONT WILL ALLOW FOR MUCH COLDER
TEMPERATURES ON SUNDAY. ANOTHER COASTAL STORM WITH ACCUMULATING SNOW
IS POSSIBLE DURING THE UPCOMING WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1225 AM EST...SNOW SHOWERS WERE MOVING ACROSS THE WESTERN
PORTION OF THE FA. THESE SNOW SHOWERS WILL TEND TO WEAKEN AS THEY
MOVE FARTHER EAST INTO DRIER AIR.
THE 3KM HRRR SHOWS THIS ACTIVITY WEAKENING AND DRYING UP AS IT
MOVES FURTHER EASTWARD...AND 00Z KALY SOUNDING WOULD SUGGEST DRY
AIR WOULD PROBABLY WIN OUT. STILL...WILL CONTINUE TO MONITOR AS IT
PROGRESSES FURTHER EASTWARD. WITH COLDER AIR AND DEEPENING
MOISTURE ALOFT ARRIVING AHEAD OF THE NEXT FRONTAL SYSTEM...PTYPE
WILL BE SNOW SHOWERS.
THE COLD FRONT LOCATED TO OUR NORTHWEST ACROSS THE EASTERN GREAT
LAKES ASSOCIATED WITH NORTHERN STREAM ENERGY WILL MOVE
SOUTHEASTWARD INTO THE AREA LATE TONIGHT. SCATTERED SNOW SHOWERS
WILL PRECEDE AND ACCOMPANY THE BOUNDARY AND SHORT WAVE FOR THE
ADIRONDACKS...WITH LITTLE ACTIVITY EXPECTED FURTHER SOUTH AND
EAST.
TEMPERATURES WILL DROP ONLY GRADUALLY TONIGHT AS THE COLD FRONT
APPROACHES...AND MAY WIND UP HOLDING STEADY FOR MANY LOCATIONS IN
THE MID TO UPPER 20S. FAR NORTHWESTERN AREAS MAY FALL LATE
TONIGHT INTO THE TEENS AS THE COLD FRONT PASSES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
THE PASSAGE OF THE COLD FRONT IS EXPECTED AROUND DAY BREAK ACROSS
THE NORTHWESTERN PORTION OF THE FORECAST AREA AND BEFORE MIDDAY
ACROSS THE SOUTHEAST. HIGHER PRESSURE WILL BEGIN TO BUILD IN BEHIND
THE BOUNDARY DURING THE AFTERNOON. THERE WILL BE LITTLE RECOVERY IN
TEMPERATURES SUNDAY WITH THE COLD AIR ADVECTION IN THE WAKE OF THE
BOUNDARY. IN ADDITION THE BRISK NORTHWESTERLY WINDS WILL MAKE IN
FEEL EVEN COLDER.
HIGH PRESSURE CENTERED TO OUR NORTH WILL PASS OVER THE REGION SUNDAY
NIGHT INTO MONDAY AS AN AREA OF LOW PRESSURE PASSES TO OUR SOUTH IN
ASSOCIATION WITH A VIGOROUS SHORT WAVE. THE SURFACE LOW IS THEN
EXPECTED TO MOVE OFF THE CAROLINA COAST ON MONDAY. HOWEVER ALOFT AN
UPPER LOW IS EXPECTED TO DEVELOP ALONG THE MID ATLANTIC COAST MONDAY
NIGHT AS THE SHORT WAVE ROTATES THROUGH THE BASE OF THE DEEP LONGWAVE
TROUGH OVER THE EASTERN UNITED STATES. THIS WILL RESULT IN FURTHER
DEVELOPMENT/DEEPENING OF THE SURFACE LOW OFF THE MID ATLANTIC COAST.
IT WILL BE COLD AND FAIR SUNDAY NIGHT AS THE RIDGE DOMINATES OUR
WEATHER. LOWS ARE FORECAST TO BE IN THE SINGLE DIGITS WITH BELOW
ZERO READINGS ACROSS THE NORTHWESTERN THIRD OF THE FORECAST AREA.
WINDS WILL BE LIGHT. TEMPERATURES MONDAY ARE EXPECTED TO RUN AROUND
10 DEGREES BELOW NORMAL.
AT THIS TIME IT APPEARS THE FORECAST AREA MAY BE ON THE NORTHERN
EDGE OF THE PRECIPITATION SHIELD MONDAY WITH GREATER AND MORE
WIDESPREAD CHANCES FOR SNOW MONDAY NIGHT AS THE SURFACE LOW
DEEPENS AND IS DRAWN UNDER THE UPPER LOW MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE LONG TERM PERIOD WILL START OFF ACTIVE...ALTHOUGH THE DEGREE OF
IMPACT IS STILL YET TO BE DETERMINED. IN ADDITION...RATHER COLD
WEATHER IS EXPECTED THROUGH THE ENTIRE LONG TERM PERIOD.
AS AN UPPER LEVEL DISTURBANCE DIVES OUT OF THE NORTHERN STREAM
TOWARDS THE EASTERN SEABOARD...A NEW AREA OF LOW PRESSURE WILL
DEVELOP OFF THE COAST AND RAPIDLY DEEPEN ON TUESDAY. THIS IS SHOWN
IN THE 12Z ECMWF...GGEM...GFS...NAM AND MOST MEMBERS OF THE 12Z
GEFS. THE UPPER LEVEL ENERGY WILL BECOME CUT OFF...ALLOWING FOR A
PROLONGED PERIOD OF PRECIP IN THE FORM OF SNOW TO OCCUR ACROSS MUCH
OF NEW ENGLAND. OUR REGION WILL BE ON THE WESTERN FRINGE OF THIS
SYSTEM...ALTHOUGH THE EXACT TRACK IS STILL FAR FROM CERTAIN. WHILE
SOME SNOW LOOKS TO OCCUR ON TUESDAY...AMOUNTS ARE STILL QUITE
UNCERTAIN...WITH THE BEST CHANCE ACROSS EASTERN PARTS OF THE AREA.
WHILE THE 12Z NAM/ECMWF BOTH HAD A LOT OF PRECIP OVER OUR AREA...THE
12Z GGEM/GFS AND 18Z NAM KEPT THE HEAVIER PRECIP TO OUR EAST. AT
THIS POINT...WILL FAVOR AREAS EAST OF THE HUDSON RIVER FOR THE MOST
SNOWFALL AND HIGHEST POPS FOR TUESDAY INTO TUESDAY NIGHT.
STILL...THERE IS POTENTIAL FOR THIS STORM TO TRACK CLOSER TO OUR
AREA AND BRING A SIGNIFICANT SNOWFALL TO THE ENTIRE CWA...AND THE
WITH THE UPPER LEVEL LOW BECOMING CUTOFF...THIS MAKES THE FORECAST
RATHER DIFFICULT AND PARTICULAR UNCERTAIN. WE WILL MENTION THIS
SYSTEM IN OUR HWO. TEMPS WILL CONTINUE TO BELOW NORMAL WITH AN
ARCTIC AIRMASS IN PLACE...WITH HIGHS ONLY IN THE TEENS AND 20S...AND
LOWS BETWEEN -10 AND 5.
BY WEDNESDAY...THE STORM WILL BE MOVING AWAY...BUT IT REMAIN COLD
AND BLUSTERY BEHIND THE SYSTEM. TEMPS WILL CONTINUE TO BE IN THE
TEENS AND 20S FOR WED...WITH SINGLE DIGITS FOR WED NIGHT. NO PRECIP
IS EXPECTED...WITH A PARTLY TO MOSTLY CLEAR SKY.
ANOTHER NORTHERN STREAM CLIPPER SYSTEM LOOK TO IMPACT THE REGION
SOMETIME BETWEEN THURSDAY AFTERNOON AND FRIDAY. A ROUND OF LIGHT
SNOW LOOKS TO SPREAD FROM WEST TO EAST ACROSS THE AREA...WITH SOME
ACCUMULATION POSSIBLE FOR ALL AREAS. TEMPS LOOK A LITTLE WARMER THAN
RECENT DAYS...WITH HIGHS IN THE 20S FOR THURS/FRI. OVERNIGHT LOWS ON
THURS NIGHT WILL BE IN THE MID TEENS TO MID 20S.
COLDER AIR WILL ARRIVE BEHIND THIS NORTHERN STREAM CLIPPER SYSTEM.
MIN ON FRI NIGHT WILL BE IN THE SINGLE DIGITS. IT WILL BE COLD AND
BLUSTERY FOR SATURDAY WITH A PARTLY CLOUDY SKY...AND HIGHS IN THE
TEENS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
MAINLY VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HOURS.
THE EXCEPTION WILL BE THIS EVENING...AS LINGERING LOW LEVEL
MOISTURE MAY ALLOW FOR A BRIEF PERIOD OF MVFR MIST/LOW
STRATUS...MAINLY FOR KGFL OR KPSF. OTHERWISE...ENOUGH OF A GRADIENT
THANKS TO AN APPROACHING COLD FRONT LATE TONIGHT SHOULD KEEP
THINGS MIXED ENOUGH TO PREVENT ANY MVFR/IFR LOW CLOUDS FROM
OCCURRING. OTHERWISE CIGS WILL BE BKN-OVC AT AROUND 5-6 KFT FOR
MOST OF THE NIGHT.
THE PASSAGE OF THE FRONT LOOKS TO OCCUR EITHER LATE TONIGHT OR
EARLY SUNDAY MORNING AFTER SUNRISE. THE WIND SHIFT WITH THIS
BOUNDARY WILL BE SUBTLE...DUE TO W-NW FLOW ALREADY IN PLACE BEHIND
THE DEPARTING COASTAL STORM. WINDS WILL BECOME MORE WESTERLY FOR
SUNDAY AT AROUND 10 KTS.
CLOUDS SHOULD DECREASE THROUGH THE DAY ON SUNDAY BEHIND THE ARCTIC
BOUNDARY...BECOMING NEARLY CLEAR IN MOST AREAS BY ABOUT MIDDAY.
LITTLE TO NO PRECIP IS EXPECTED WITH THE PASSAGE OF THE BOUNDARY
FOR VALLEY SITES DUE TO LIMITED MOISTURE.
OUTLOOK...
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SN.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SN.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDRO PROBLEMS ARE EXPECTED THROUGH EARLY NEXT WEEK.
THE PRECIPITATION THAT DOES OCCUR WILL BE IN THE FORM OF SNOW.
ICE WILL CONTINUE TO THICKEN ON RIVERS...STREAMS...CREEKS...LAKES
AND OTHER BODIES OF WATER.
THE EAGLE BRIDGE GAGE ON THE HOOSIC RIVER CONTINUES TO BE HAMPERED
BY ICE EFFECTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/11
NEAR TERM...IAA/FRUGIS/11
SHORT TERM...IAA
LONG TERM...FRUGIS
AVIATION...FRUGIS
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
105 PM EST SUN JAN 25 2015
.SYNOPSIS...
A STRONG COLD FRONT WILL CONTINUE TO PUSH SOUTHEAST THROUGH OUR
REGION TODAY, REACHING A LATE DAY POSITION FROM THE DELMARVA WEST
INTO LOW PRESSURE OVER THE LOWER OHIO VALLEY. THAT LOW WILL REACH
THE NORTH CAROLINA COAST MONDAY MORNING THEN TURN NORTH NORTHEAST,
INTENSIFYING VERY RAPIDLY AS IT NEARS CAPE COD TUESDAY. HIGH
PRESSURE FOLLOWS BY LATE WEDNESDAY, THEN ANOTHER LOW WILL
REDEVELOP ON THE NEXT COLD FRONTAL PASSAGE OFF THE MID ATLANTIC
COAST LATE THURSDAY AND FRIDAY. HIGH PRESSURE FOLLOWS SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WITH THE 12:30 PM UPDATE, WE HAVE INCREASED TEMPERATURES FROM PHL
SOUTH AHEAD OF A COLD FRONT ALONG WITH CLOUD COVER FOR THE
REMAINDER OF THE AFTERNOON. THIS CLOUD COVER SHOULD KEEP THE
TEMPERATURES IN CHECK FROM WARMING TO MUCH MORE AS THE DAY GOES
ON. THE LATEST RAP AND HRRR HOLD OFF ANY PRECIPITATION TILL THIS
EVENING, THIS FORECAST UPDATE TAKES OUT AMY MENTION OF
PRECIPITATION TILL THIS EVENING.
OTHERWISE, AS THE LOW PRESSURE FROM YESTERDAY PULLS FARTHER TO
OUR NORTHEAST AN ARCTIC-TYPE COLD FRONT PUSHES THROUGH OUR REGION
FROM LATE MORNING AND THROUGH THIS AFTERNOON. WATER VAPOR IMAGERY
THIS MORNING SHOWS ONE TROUGH AXIS TO OUR NORTHEAST WHILE ANOTHER
SHORTWAVE AXIS PUSHES THROUGH THE GREAT LAKES...THIS IS DRIVING
THE ARCTIC FRONT TODAY. WAY BACK ACROSS THE NORTHERN PLAINS IS THE
ENERGY THAT WILL BE THE DRIVING FORCE FOR THE CLIPPER SYSTEM LATE
TONIGHT AND THEN THE MUCH LARGER COASTAL NOR`EASTER EXPECTED ON
MONDAY- TUESDAY.
OVERALL A MAINLY DRY AND TRANQUIL DAY IS EXPECTED ACROSS THE
REGION. THE AFOREMENTIONED FRONT WILL SLIP THROUGH THE REGION BY
THIS AFTERNOON USHERING IN A COOLER AIRMASS. THE MORNING STRATOCU
SHOULD LIFT AND MIX OUT A LITTLE AS THE DAY WEARS ON. DECENT
DOWNSLOPING COMPONENT SHOULD ALLOW HIGHS TO REACH AROUND 40F THIS
AFTERNOON, SLIGHTLY WARMER SOUTH AND EAST OF PHILLY, AHEAD OF THE
FRONTAL PASSAGE. BEHIND THE FRONT WEAK MID-LEVEL WARM AIR
ADVECTION OCCURS TO OUR SOUTHWEST AS MORE MOISTURE AND CLOUDS
ADVECT IN BEGINNING LATER THIS EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
BROAD SCALE SURFACE LOW PRESSURE, RIDING ALONG THE SAGGING COLD
FRONT LATER THIS EVENING, WILL PASS TO OUR SOUTH TONIGHT. HIGH
PRESSURE TO OUR NORTH WITH WEAK MID-LEVEL RIDGING WILL ALLOW FOR THE
MID-LEVEL SHORTWAVE DRIVING THE SURFACE LOW TO DEEPEN AND TAKE MORE
OF A NEGATIVE TILT TONIGHT. STRENGTHENING WAA, IN RESPONSE TO THIS
PROCESS, WILL OCCUR ACROSS OUR REGION AS A LIGHT SNOW SHOULD BREAK
OUT FROM WEST-EAST. ONSET TIMING IS STILL A BIT OF A QUESTION BUT A
MAJORITY OF THE HI-RES GUIDANCE IS SHOWING THE INCREASING CHANCES
DURING THE LATE EVENING. PTYPE SHOULD NOT BE MUCH OF AN ISSUE EXCEPT
ACROSS OUR EXTREME SOUTHERN ZONES AS LOW-LEVEL TEMPERATURES STRUGGLE
TO TRANSITION COLDER (BELOW 0C) JUST AHEAD OF THE APPROACHING
LOW...WAA SHOULD KEEP A RAIN/SNOW MIX SOUTH OF DOVER WHILE NORTHWARD
IS ALL SNOW.
DECENT CONVERGENCE ACROSS OUR CENTRAL ZONES LATE TONIGHT, BOTH
THERMALLY AND DYNAMICALLY. GUIDANCE IS PAINTING A NOSE OF A TENTH OF
LIQUID FROM A PHL/ABE LINE WEST SO THIS IS WHERE WE SHOULD SEE
SLIGHTLY HIGHER SNOW AMOUNTS...ON THE ORDER OF 1-2" IN AND AROUND
PHILLY, 2-3" FARTHER WEST TOWARDS RDG...MESOSCALE BANDING POTENTIAL
ALSO EXISTS ALBEIT NOT NEARLY AS ROBUST AS SATURDAY MORNING.
EVEN THOUGH THIS SNOW WILL AFFECT THE MONDAY MORNING COMMUTE WE DID
NOT WANT TO ADD TO ANY CONFUSION WITH MULTIPLE WINTER WEATHER
HEADLINES DEALING WITH THE SAME EVENT...JUST TWO DIFFERENT PIECES OF
ENERGY. GIVEN WE ARE EXPECTING A MUCH MORE IMPACTFUL STORM BEGINNING
LATER ON MONDAY...SEE LONG TERM DISCO...WE DECIDED TO FORGO AN
ADVISORY BUT MAKE MENTION OF THE EARLY MORNING SNOWFALL IN THE
HWO/WSW PRODUCTS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
**MAJOR DISRUPTIVE SNOWSTORM POTENTIAL LATE MONDAY INTO TUESDAY
MORNING PHILLY AREA NEWD TO NEW ENGLAND...WINTER STORM WATCH IN
PLACE FOR MOST OF THE FORECAST AREA**
**BLIZZARD WATCH HAS BEEN ISSUED FOR MONMOUTH, OCEAN, AND
MIDDLESEX COUNTIES**
500 MB: A STRONG SHORT WAVE MONDAY MORNING OVER THE CENTRAL APPALACHIANS
INTENSIFIES INTO A CLOSED LOW SOUTH OF LONG ISLAND TUESDAY. RIDGING
IN THE WAKE OF ITS MARITIMES DEPARTURE FOLLOWS TO THE EAST COAST
WEDNESDAY. A SOUTHEASTWARD MOVING SHORT WAVE REACHES THE MID
ATLANTIC COAST FRIDAY WITH A TEMPORARILY FLATTENED WESTERLY FLOW
NEXT WEEKEND.
TEMPERATURES (ENERGY USE): BELOW NORMAL MONDAY THROUGH THURSDAY,
POSSIBLY 5 TO 10 DEGREES BELOW MON-WED; NEAR NORMAL FRI, CHILLING
AGAIN SATURDAY.
FORECAST BASIS: UNLESS OTHERWISE NOTED WITHIN THE DAILIES. THIS
FORECAST IS A 50 50 BLEND OF THE 00Z/25 MAV/MET FOR MONDAY-TUESDAY.
THE 00Z/25 MEX MOS WAS APPLIED TUESDAY NIGHT AND WEDNESDAY. THE 05Z/25
WPC D4-8 ELEMENTS OF DEWPOINTS/WIND/SKY/POP/MAX-MIN TEMPS WERE NOT USED
FOR THE LONGER RANGE DUE TO FOCUS ON THE POTENTIALLY VERY HIGH IMPACT
STORM FOR MONDAY NIGHT.
THEREFORE...THERE WAS NO UPDATE OF THE FORECAST BEYOND WEDNESDAY
IN THE EARLY ISSUANCE TODAY.
THE DAILIES...
MONDAY-TUESDAY...WSA IN DIFFERING SEGMENTS TO BE REFINED WHEN
WATCHES CONVERT TO WARNINGS AND OR ADVISORIES.
MODEL DISAGREEMENT FOR THE 00Z/25 CYCLE WITH THE NAM THE MAIN OUTLIER
RIGHT NOW. THE UKMET IS LARGE BUT A FASTER DEPARTURE THAN THE ECMWF.
THE 00Z/06ZNAM WAS ACCEPTABLE THROUGH MIDDAY MONDAY AND THEREAFTER
DID NOT RELY ON THE NAM FOR ITS QPF...INSTEAD THIS FORECAST IS
BASED HEAVILY ON NCEP QPF/SNOWFALL AS WELL AS THE 00Z/25 ECMWF
AND GFS BLEND.
MONDAY: SEVERAL INCHES OF SNOW EXPECTED BUT AN ADVISORY NOT ISSUED
SINCE WE DID NOT WISH TO DRAW ATTENTION AWAY FROM THE POTENTIALLY
VERY HIGH IMPACT EVENT FOR MONDAY NIGHT. TOO WARM FOR MUCH ACCUMULATION
FAR SNJ AND MUCH OF THE DELMARVA. THE ARCTIC FRONT AND ITS SLOWLY
DEEPENING BOUNDARY LAYER COLD IS CRUCIAL FOR THE LIFT OF THE SELY
850MB FLOW AND A GENERAL SNOW IN EASTERN PA/MUCH OF NJ. COMMUTES
IMPACTED. HIGH CONFIDENCE.
MONDAY NIGHT INTO TUESDAY MORNING...UNCERTAINTY ON AMOUNTS ETC ALL
HINGING ON INTENSITY AND TRACK OF A COASTAL STORM. OVERALL, THIS
LOOKS LIKE A MAJOR STORM FOR US AND POTENTIAL FOR BLIZZARD CONDITIONS
IN NE NJ. OUR FORECAST AMOUNTS ARE PROBABLY CONSERVATIVE.
BANDING IN THE COMMA HEAD WITH A BENT BACK FRONT ALOFT LOOKS TO BE
A MAJOR PLAYER...GENERATING SNOWFALL RATES MONDAY NIGHT POSSIBLY
IN EXCESS OF AN INCH AN HOUR ACROSS NJ AND PORTIONS OF E PA. IF
THE 00Z/06Z NAM MASS FIELDS ALOFT ARE CORRECT THEN ALL THIS HEAVY SNOW
WOULD MISS TO THE EAST.
THOSE WITH TRAVEL PLANS IN E PA AND NJ ESPECIALLY FOR MONDAY NIGHT
AND TUESDAY SHOULD BE AWARE THAT THOSE PLANS MAY NEED MAJOR
ALTERATION/CANCELLATION. BE PREPARED WITH ALTERNATE PLANS. "IF"
CONFIDENCE IS VERY HIGH, WE MAY CONVERT TO WARNINGS LATE TODAY.
WATCHES DO NOT MEAN A DONE DEAL BUT DO PAY ATTENTION. A DRIER
MORE POWDERY SNOW WILL BE EASIER TO ACCUMULATE IN THE COLDER
AIRMASS THAN JUST WHAT OCCURRED EARLY SATURDAY. WIND WILL BECOME A
FACTOR IN BLOWING/DRIFTING, MAINLY IN NJ/DEL.
TUE NIGHT THRU WED NIGHT... HIGH PRESSURE WILL DOMINATE DURING THIS
PERIOD WITH FAIR BUT COLD WEATHER EXPECTED.
THU INTO FRI...THIS FORECAST WAS NOT UPDATED ON THIS MID SHIFT.
MODELS ARE SHOWING ANOTHER CLIPPER TYPE SYSTEM APPROACHING FROM
THE WEST AFTER THE MID WEEK PERIOD. TEMPERATURES WILL HAVE BEGUN
TO MODERATE BY THE TIME THE PRECIP ARRIVES...SO SOME RAIN/SNOW
LINE ISSUES WILL OCCUR. MOSTLY USED CHC POPS FOR NOW. TEMPS WILL
STILL BE BELOW NORMAL...BUT NOT AS COLD AS WED.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR CIGS AOA 4000 FT. STRATOCU DECK WILL REMAIN IN PLACE
MOST OF THE DAY UNDER WESTERLY WINDS WITH A FEW GUSTS POSSIBLE TO
NEAR 20 KT.
TONIGHT...MVFR/IFR IN AREAS OF SNOW. TIMING IS STILL A BIT SUSPECT
BUT LIGHT SNOW SHOULD OVERSPREAD FROM THE WEST-EAST BY LATE TONIGHT.
MINIMAL RAIN/SNOW MIXING EXPECTED VCNTY KMIV TOWARD 12Z MONDAY.
EXPECT SOME LIGHT ACCUMULATIONS THROUGH EARLY MONDAY MORNING...AROUND
1-2 INCHES PHL/ILG/TTN/PNE, MAYBE 2-3 INCHES RDG/ABE.
OUTLOOK...
MON AND MON NIGHT...IFR/LIFR SOUTH AND MVFR OR INTERMITTENT IFR
NORTH IN SNOW OR PERIODS OF SNOW. N-NE WINDS GUSTING 20-30 KT AT
TIMES WITH 35 KT GUSTS POSSIBLE VCNTY KACY. VERY HIGH CONFIDENCE.
PLOWABLE AMOUNTS AND POTENTIAL FOR AIRPORT CLOSURES AT NIGHT INTO
EARLY TUESDAY DEPENDENT ON SNOW AMOUNTS AND RATE OF FALL AS WELL
AS DRIFTING.
TUE...IFR PROBABLE EARLY IN COMMA HEAD BENT BACK BANDING OF THE BIG
NOREASTER THEN PROBABLY BECOMING VFR BY LATE IN THE DAY. NORTHWEST
WINDS GUSTING 20-30KT, EXCEPT POSSIBLY STRONGER VCNTY KACY.
AVERAGE CONFIDENCE.
TUESDAY NIGHT-WED: MOSTLY VFR. N-NW WINDS. HIGH CONFIDENCE:
THURSDAY: CONDITIONS MAY DEGRADE IN A PERIOD OF PCPN DURING THE
AFTERNOON OR NIGHT.
&&
.MARINE...
REST OF TODAY...WE REMOVED THE SCA FROM THE OCEAN FRONT AS WINDS AND
SEAS HAVE FALLEN BELOW THRESHOLDS.
TONIGHT...SUB-SCA EXPECTED. LOW PRESSURE WILL MOVE BY TO OUR SOUTH
LATE AS WINDS VEER TOWARDS THE NORTH-NORTHEAST. SEAS BEGIN TO BUILD
ACROSS THE SOUTHERN WATERS LATE AS DO THE WINDS. GALE WARNINGS/STORM
WATCHES IN PLACE STARTING MONDAY AFTERNOON.
OUTLOOK...
MONDAY INTO TUESDAY...MOSTLY GALE CONDITIONS ON THE WATERS BUT POCKETS
OF STORM FORCE GUSTS. HAVE FORECAST WHERE THE STORM FORCE 50 KT GUSTS
OVER THE NJ WATER WHERE THEY ARE MOST LIKELY TO OCCUR, BUT WITH THE
UNDERSTANDING THAT ISOLATED STORM FORCE GUSTS MAY OCCUR IN THE
DELAWARE WATERS AS WELL. THE HEADLINES ARE THE MOST LIKELY WORST
CASE SCENARIO.
TUESDAY AFTERNOON THROUGH THURSDAY...MAINLY SCA CONDITIONS WITH
AREAS OF FREEZING SPRAY EXPECTED.
&&
.TIDES/COASTAL FLOODING...
ANOTHER NORTHEASTER IS EXPECTED TO AFFECT THE COASTAL WATERS OF
DELAWARE AND NEW JERSEY FROM MONDAY NIGHT INTO TUESDAY. MINOR TO
POSSIBLY MODERATE TIDAL FLOODING SHOULD OCCUR AROUND THE TIMES OF
HIGH TIDE, MAINLY THE MIDNIGHT TUESDAY MORNING HIGH TIDE CYCLE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR PAZ054-055-060>062-070-071-101>106.
NJ...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR NJZ001-007>010-015>019-027.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR NJZ021>025.
BLIZZARD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR NJZ012>014-020-026.
DE...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR DEZ001.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR DEZ002>004.
MD...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR MDZ008.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR MDZ012-015-019-020.
MARINE...STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
ANZ450>453.
GALE WARNING FROM 11 AM MONDAY TO 11 AM EST TUESDAY FOR ANZ431-
454-455.
GALE WARNING FROM 5 PM MONDAY TO 11 AM EST TUESDAY FOR ANZ430.
&&
$$
SYNOPSIS...DRAG/KLINE
NEAR TERM...GAINES/HEAVENER/KLINE
SHORT TERM...HEAVENER
LONG TERM...DRAG/KLINE
AVIATION...DRAG/HEAVENER/KLINE
MARINE...DRAG/HEAVENER/KLINE
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1233 PM EST SUN JAN 25 2015
.SYNOPSIS...
A STRONG COLD FRONT WILL CONTINUE TO PUSH SOUTHEAST THROUGH OUR
REGION TODAY, REACHING A LATE DAY POSITION FROM THE DELMARVA WEST
INTO LOW PRESSURE OVER THE LOWER OHIO VALLEY. THAT LOW WILL REACH
THE NORTH CAROLINA COAST MONDAY MORNING THEN TURN NORTH NORTHEAST,
INTENSIFYING VERY RAPIDLY AS IT NEARS CAPE COD TUESDAY. HIGH
PRESSURE FOLLOWS BY LATE WEDNESDAY, THEN ANOTHER LOW WILL
REDEVELOP ON THE NEXT COLD FRONTAL PASSAGE OFF THE MID ATLANTIC
COAST LATE THURSDAY AND FRIDAY. HIGH PRESSURE FOLLOWS SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WITH THE 12:30 PM UPDATE, WE HAVE INCREASED TEMPERATURES FROM PHL
SOUTH AHEAD OF A COLD FRONT ALONG WITH CLOUD COVER FOR THE
REMAINDER OF THE AFTERNOON. THIS CLOUD COVER SHOULD KEEP THE
TEMPERATURES IN CHECK FROM WARMING TO MUCH MORE AS THE DAY GOES
ON. THE LATEST RAP AND HRRR HOLD OFF ANY PRECIPITATION TILL THIS
EVENING, THIS FORECAST UPDATE TAKES OUT AMY MENTION OF
PRECIPITATION TILL THIS EVENING.
OTHERWISE, AS THE LOW PRESSURE FROM YESTERDAY PULLS FARTHER TO
OUR NORTHEAST AN ARCTIC-TYPE COLD FRONT PUSHES THROUGH OUR REGION
FROM LATE MORNING AND THROUGH THIS AFTERNOON. WATER VAPOR IMAGERY
THIS MORNING SHOWS ONE TROUGH AXIS TO OUR NORTHEAST WHILE ANOTHER
SHORTWAVE AXIS PUSHES THROUGH THE GREAT LAKES...THIS IS DRIVING
THE ARCTIC FRONT TODAY. WAY BACK ACROSS THE NORTHERN PLAINS IS THE
ENERGY THAT WILL BE THE DRIVING FORCE FOR THE CLIPPER SYSTEM LATE
TONIGHT AND THEN THE MUCH LARGER COASTAL NOR`EASTER EXPECTED ON
MONDAY- TUESDAY.
OVERALL A MAINLY DRY AND TRANQUIL DAY IS EXPECTED ACROSS THE
REGION. THE AFOREMENTIONED FRONT WILL SLIP THROUGH THE REGION BY
THIS AFTERNOON USHERING IN A COOLER AIRMASS. THE MORNING STRATOCU
SHOULD LIFT AND MIX OUT A LITTLE AS THE DAY WEARS ON. DECENT
DOWNSLOPING COMPONENT SHOULD ALLOW HIGHS TO REACH AROUND 40F THIS
AFTERNOON, SLIGHTLY WARMER SOUTH AND EAST OF PHILLY, AHEAD OF THE
FRONTAL PASSAGE. BEHIND THE FRONT WEAK MID-LEVEL WARM AIR
ADVECTION OCCURS TO OUR SOUTHWEST AS MORE MOISTURE AND CLOUDS
ADVECT IN BEGINNING LATER THIS EVENING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
BROAD SCALE SURFACE LOW PRESSURE, RIDING ALONG THE SAGGING COLD
FRONT LATER THIS EVENING, WILL PASS TO OUR SOUTH TONIGHT. HIGH
PRESSURE TO OUR NORTH WITH WEAK MID-LEVEL RIDGING WILL ALLOW FOR THE
MID-LEVEL SHORTWAVE DRIVING THE SURFACE LOW TO DEEPEN AND TAKE MORE
OF A NEGATIVE TILT TONIGHT. STRENGTHENING WAA, IN RESPONSE TO THIS
PROCESS, WILL OCCUR ACROSS OUR REGION AS A LIGHT SNOW SHOULD BREAK
OUT FROM WEST-EAST. ONSET TIMING IS STILL A BIT OF A QUESTION BUT A
MAJORITY OF THE HI-RES GUIDANCE IS SHOWING THE INCREASING CHANCES
DURING THE LATE EVENING. PTYPE SHOULD NOT BE MUCH OF AN ISSUE EXCEPT
ACROSS OUR EXTREME SOUTHERN ZONES AS LOW-LEVEL TEMPERATURES STRUGGLE
TO TRANSITION COLDER (BELOW 0C) JUST AHEAD OF THE APPROACHING
LOW...WAA SHOULD KEEP A RAIN/SNOW MIX SOUTH OF DOVER WHILE NORTHWARD
IS ALL SNOW.
DECENT CONVERGENCE ACROSS OUR CENTRAL ZONES LATE TONIGHT, BOTH
THERMALLY AND DYNAMICALLY. GUIDANCE IS PAINTING A NOSE OF A TENTH OF
LIQUID FROM A PHL/ABE LINE WEST SO THIS IS WHERE WE SHOULD SEE
SLIGHTLY HIGHER SNOW AMOUNTS...ON THE ORDER OF 1-2" IN AND AROUND
PHILLY, 2-3" FARTHER WEST TOWARDS RDG...MESOSCALE BANDING POTENTIAL
ALSO EXISTS ALBEIT NOT NEARLY AS ROBUST AS SATURDAY MORNING.
EVEN THOUGH THIS SNOW WILL AFFECT THE MONDAY MORNING COMMUTE WE DID
NOT WANT TO ADD TO ANY CONFUSION WITH MULTIPLE WINTER WEATHER
HEADLINES DEALING WITH THE SAME EVENT...JUST TWO DIFFERENT PIECES OF
ENERGY. GIVEN WE ARE EXPECTING A MUCH MORE IMPACTFUL STORM BEGINNING
LATER ON MONDAY...SEE LONG TERM DISCO...WE DECIDED TO FORGO AN
ADVISORY BUT MAKE MENTION OF THE EARLY MORNING SNOWFALL IN THE
HWO/WSW PRODUCTS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
**MAJOR DISRUPTIVE SNOWSTORM POTENTIAL LATE MONDAY INTO TUESDAY
MORNING PHILLY AREA NEWD TO NEW ENGLAND...WINTER STORM WATCH IN
PLACE FOR MOST OF THE FORECAST AREA**
**BLIZZARD WATCH HAS BEEN ISSUED FOR MONMOUTH, OCEAN, AND
MIDDLESEX COUNTIES**
500 MB: A STRONG SHORT WAVE MONDAY MORNING OVER THE CENTRAL APPALACHIANS
INTENSIFIES INTO A CLOSED LOW SOUTH OF LONG ISLAND TUESDAY. RIDGING
IN THE WAKE OF ITS MARITIMES DEPARTURE FOLLOWS TO THE EAST COAST
WEDNESDAY. A SOUTHEASTWARD MOVING SHORT WAVE REACHES THE MID
ATLANTIC COAST FRIDAY WITH A TEMPORARILY FLATTENED WESTERLY FLOW
NEXT WEEKEND.
TEMPERATURES (ENERGY USE): BELOW NORMAL MONDAY THROUGH THURSDAY,
POSSIBLY 5 TO 10 DEGREES BELOW MON-WED; NEAR NORMAL FRI, CHILLING
AGAIN SATURDAY.
FORECAST BASIS: UNLESS OTHERWISE NOTED WITHIN THE DAILIES. THIS
FORECAST IS A 50 50 BLEND OF THE 00Z/25 MAV/MET FOR MONDAY-TUESDAY.
THE 00Z/25 MEX MOS WAS APPLIED TUESDAY NIGHT AND WEDNESDAY. THE 05Z/25
WPC D4-8 ELEMENTS OF DEWPOINTS/WIND/SKY/POP/MAX-MIN TEMPS WERE NOT USED
FOR THE LONGER RANGE DUE TO FOCUS ON THE POTENTIALLY VERY HIGH IMPACT
STORM FOR MONDAY NIGHT.
THEREFORE...THERE WAS NO UPDATE OF THE FORECAST BEYOND WEDNESDAY
IN THE EARLY ISSUANCE TODAY.
THE DAILIES...
MONDAY-TUESDAY...WSA IN DIFFERING SEGMENTS TO BE REFINED WHEN
WATCHES CONVERT TO WARNINGS AND OR ADVISORIES.
MONMOUTH AND OCEAN COUNTIES OF NE NJ ARE SEPARATED AS WINTER STORM
WATCH, BUT READY TO TO CONVERT TO A BLIZZARD WARNING IF THREE
SUCCESSIVE RUNS OF THE ECMWF OPERATIONAL AND ENSEMBLE SOLUTIONS
ARE CORRECT.
MODEL DISAGREEMENT FOR THE 00Z/25 CYCLE WITH THE NAM THE MAIN OUTLIER
RIGHT NOW. THE UKMET IS LARGE BUT A FASTER DEPARTURE THAN THE ECMWF.
THE 00Z/06ZNAM WAS ACCEPTABLE THROUGH MIDDAY MONDAY AND THEREAFTER
DID NOT RELY ON THE NAM FOR ITS QPF...INSTEAD THIS FORECAST IS
BASED HEAVILY ON NCEP QPF/SNOWFALL AS WELL AS THE 00Z/25 ECMWF
AND GFS BLEND.
MONDAY: SEVERAL INCHES OF SNOW EXPECTED BUT AN ADVISORY NOT ISSUED
SINCE WE DID NOT WISH TO DRAW ATTENTION AWAY FROM THE POTENTIALLY
VERY HIGH IMPACT EVENT FOR MONDAY NIGHT. TOO WARM FOR MUCH ACCUMULATION
FAR SNJ AND MUCH OF THE DELMARVA. THE ARCTIC FRONT AND ITS SLOWLY
DEEPENING BOUNDARY LAYER COLD IS CRUCIAL FOR THE LIFT OF THE SELY
850MB FLOW AND A GENERAL SNOW IN EASTERN PA/MUCH OF NJ. COMMUTES
IMPACTED. HIGH CONFIDENCE.
MONDAY NIGHT INTO TUESDAY MORNING...UNCERTAINTY ON AMOUNTS ETC ALL
HINGING ON INTENSITY AND TRACK OF A COASTAL STORM. OVERALL, THIS
LOOKS LIKE A MAJOR STORM FOR US AND POTENTIAL FOR BLIZZARD CONDITIONS
IN NE NJ. OUR FORECAST AMOUNTS ARE PROBABLY CONSERVATIVE.
BANDING IN THE COMMA HEAD WITH A BENT BACK FRONT ALOFT LOOKS TO BE
A MAJOR PLAYER...GENERATING SNOWFALL RATES MONDAY NIGHT POSSIBLY
IN EXCESS OF AN INCH AN HOUR ACROSS NJ AND PORTIONS OF E PA. IF
THE 00Z/06Z NAM MASS FIELDS ALOFT ARE CORRECT THEN ALL THIS HEAVY SNOW
WOULD MISS TO THE EAST.
THOSE WITH TRAVEL PLANS IN E PA AND NJ ESPECIALLY FOR MONDAY NIGHT
AND TUESDAY SHOULD BE AWARE THAT THOSE PLANS MAY NEED MAJOR
ALTERATION/CANCELLATION. BE PREPARED WITH ALTERNATE PLANS. "IF"
CONFIDENCE IS VERY HIGH, WE MAY CONVERT TO WARNINGS LATE TODAY.
WATCHES DO NOT MEAN A DONE DEAL BUT DO PAY ATTENTION. A DRIER
MORE POWDERY SNOW WILL BE EASIER TO ACCUMULATE IN THE COLDER
AIRMASS THAN JUST WHAT OCCURRED EARLY SATURDAY. WIND WILL BECOME A
FACTOR IN BLOWING/DRIFTING, MAINLY IN NJ/DEL.
TUE NIGHT THRU WED NIGHT... HIGH PRESSURE WILL DOMINATE DURING THIS
PERIOD WITH FAIR BUT COLD WEATHER EXPECTED.
THU INTO FRI...THIS FORECAST WAS NOT UPDATED ON THIS MID SHIFT.
MODELS ARE SHOWING ANOTHER CLIPPER TYPE SYSTEM APPROACHING FROM
THE WEST AFTER THE MID WEEK PERIOD. TEMPERATURES WILL HAVE BEGUN
TO MODERATE BY THE TIME THE PRECIP ARRIVES...SO SOME RAIN/SNOW
LINE ISSUES WILL OCCUR. MOSTLY USED CHC POPS FOR NOW. TEMPS WILL
STILL BE BELOW NORMAL...BUT NOT AS COLD AS WED.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR CIGS AOA 4000 FT. STRATOCU DECK WILL REMAIN IN PLACE
MOST OF THE DAY UNDER WESTERLY WINDS WITH SOME GUSTS EXPECTED TO
NEAR 20 KT WITH THE CFP LATER THIS MORNING.
TONIGHT...MVFR/IFR IN AREAS OF SNOW. TIMING IS STILL A BIT SUSPECT
BUT LIGHT SNOW SHOULD OVERSPREAD FROM THE WEST-EAST BY LATE TONIGHT.
MINIMAL RAIN/SNOW MIXING EXPECTED VCNTY KMIV TOWARD 12Z MONDAY.
EXPECT SOME LIGHT ACCUMULATIONS THROUGH EARLY MONDAY MORNING...AROUND
1-2 INCHES PHL/ILG/TTN/PNE, MAYBE 2-3 INCHES RDG/ABE.
OUTLOOK...
MON AND MON NIGHT...IFR/LIFR SOUTH AND MVFR OR INTERMITTENT IFR
NORTH IN SNOW OR PERIODS OF SNOW. N-NE WINDS GUSTING 20-30 KT AT
TIMES WITH 35 KT GUSTS POSSIBLE VCNTY KACY. VERY HIGH CONFIDENCE.
PLOWABLE AMOUNTS AND POTENTIAL FOR AIRPORT CLOSURES AT NIGHT INTO
EARLY TUESDAY DEPENDENT ON SNOW AMOUNTS AND RATE OF FALL AS WELL
AS DRIFTING.
TUE...IFR PROBABLE EARLY IN COMMA HEAD BENT BACK BANDING OF THE BIG
NOREASTER THEN PROBABLY BECOMING VFR BY LATE IN THE DAY. NORTHWEST
WINDS GUSTING 20-30KT, EXCEPT POSSIBLY STRONGER VCNTY KACY.
AVERAGE CONFIDENCE.
TUESDAY NIGHT-WED: MOSTLY VFR. N-NW WINDS. HIGH CONFIDENCE:
THURSDAY: CONDITIONS MAY DEGRADE IN A PERIOD OF PCPN DURING THE
AFTERNOON OR NIGHT.
&&
.MARINE...
TODAY...WE REMOVED THE SCA ON THE BAY AS WINDS AND SEAS ARE BELOW
THRESHOLDS. THE OCEAN FRONT CONTINUES TO GO THROUGH 18Z TODAY THOUGH
IT IS POSSIBLE THAT OUR SOUTHERN WATERS MAY BE PULLED SOONER AS SEAS
CONTINUE TO SUBSIDE THROUGHOUT THE MORNING.
TONIGHT...SUB-SCA EXPECTED. LOW PRESSURE WILL MOVE BY TO OUR SOUTH
LATE AS WINDS VEER TOWARDS THE NORTH-NORTHEAST. SEAS BEGIN TO BUILD
ACROSS THE SOUTHERN WATERS LATE AS DO THE WINDS. GALE WARNINGS/STORM
WATCHES IN PLACE STARTING MONDAY AFTERNOON.
OUTLOOK...
MONDAY INTO TUESDAY...MOSTLY GALE CONDITIONS ON THE WATERS BUT POCKETS
OF STORM FORCE GUSTS. HAVE FORECAST WHERE THE STORM FORCE 50 KT GUSTS
OVER THE NJ WATER WHERE THEY ARE MOST LIKELY TO OCCUR, BUT WITH THE
UNDERSTANDING THAT ISOLATED STORM FORCE GUSTS MAY OCCUR IN THE
DELAWARE WATERS AS WELL. THE HEADLINES ARE THE MOST LIKELY WORST
CASE SCENARIO.
TUESDAY AFTERNOON THROUGH THURSDAY...MAINLY SCA CONDITIONS WITH
AREAS OF FREEZING SPRAY EXPECTED.
&&
.TIDES/COASTAL FLOODING...
ANOTHER NORTHEASTER IS EXPECTED TO AFFECT THE COASTAL WATERS OF
DELAWARE AND NEW JERSEY FROM MONDAY NIGHT INTO TUESDAY. MINOR TO
POSSIBLY MODERATE TIDAL FLOODING SHOULD OCCUR AROUND THE TIMES OF
HIGH TIDE, MAINLY THE MIDNIGHT TUESDAY MORNING HIGH TIDE CYCLE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR PAZ054-055-060>062-070-071-101>106.
NJ...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR NJZ001-007>010-015>019-027.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR NJZ021>025.
BLIZZARD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR NJZ012>014-020-026.
DE...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR DEZ001.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR DEZ002>004.
MD...WINTER STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR MDZ008.
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR MDZ012-015-019-020.
MARINE...STORM WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR
ANZ450>453.
SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
ANZ450>455.
GALE WARNING FROM 11 AM MONDAY TO 11 AM EST TUESDAY FOR ANZ431-
454-455.
GALE WARNING FROM 5 PM MONDAY TO 11 AM EST TUESDAY FOR ANZ430.
&&
$$
SYNOPSIS...DRAG
NEAR TERM...GAINES/HEAVENER/KLINE
SHORT TERM...HEAVENER
LONG TERM...DRAG/KLINE
AVIATION...DRAG/HEAVENER
MARINE...DRAG/HEAVENER
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
409 PM CST SUN JAN 25 2015
.SHORT TERM...
206 PM CST
TONIGHT THROUGH MONDAY NIGHT...
COOL AIR HAS STRUGGLED TO SLIDE SOUTH THIS AFTERNOON...HOWEVER TEMPS
ARE BEGINNING TO FALL INTO THE UPR 20S ACROSS FAR NORTHEAST IL.
ACROSS THE CENTRAL/SOUTHERN CWFA TEMPS REMAIN IN THE LOW 30S WITH
DEW POINT DEPRESSIONS NOT MUCH MORE THAN 1 TO 2 DEGREES. NORTH OF
I-80 PRECIP IS MAINLY FLURRIES...WITH A RAIN/SNOW MIX SLOWLY
CHANGING TO ALL SNOW LATER THIS AFTERNOON ACROSS THE SOUTHERN CWFA.
THE SHORTWAVE THAT BROUGHT THE LIGHT SNOW CONTINUES TO SLIDE EAST
ACROSS SOUTHERN IL...AND WILL STEADILY BRING AN END TO THE PRECIP
ACROSS THE FORECAST AREA THIS EVENING FROM NORTHWEST TO SOUTHEAST.
WINDS WILL GRADUALLY DIMINISH AS WELL AS THE PRESSURE GRADIENT
RELAXES.
SFC RIDGE CENTERED TO THE NORTH THIS AFTERNOON...WILL SAG SOUTH AND
EXPAND TO COVER A PORTION OF THE WESTERN GREAT LAKES/MISSOURI VALLEY
OVERNIGHT. WHILE SOME EROSION TO THE CLOUDS IS PROBABLE NORTH OF THE
FORECAST AREA...EXPECT SOME DECREASE IN CLOUDS CLOSER TO DAYBREAK
MON. CURRENTLY EXPECT OVERNIGHT LOWS TO DIP INTO THE MID/UPR
TEENS...HOWEVER THIS WILL LIKELY NOT OCCUR UNTIL CLOSER TO DAYBREAK
MON.
THE BRIEF BREAK IN CLOUDS MON MORNING WILL QUICKLY GIVE WAY TO THE
NEXT CLIPPER SYSTEM ARRIVING MON AFTN/EVE. GUIDANCE HAS MAINTAINED A
PROGRESSIVE LOOK TO THIS NEXT WAVE...HOWEVER OPERATIONAL SOLUTIONS
ARE EQUALLY BULLISH ON EROSION OF MOISTURE WITHIN THE LOWEST FEW
LAYERS OF THE ATMOS LATE MON NGT. HAVE SOME CONCERN ABOUT P-TYPE MON
AFTN/EVE. AT THE ONSET MOISTURE WILL QUICKLY SATURATE THRU THE -10
DEG C LAYER AND TOUCH THE FAVORED DGZ...HOWEVER THE DEPTH OF THE
MOISTURE BECOMES MORE SHALLOW MON EVE. ALONG WITH THE LACK OF GOOD
LIFT AND SHALLOW MOISTURE...IT IS LOOKING MORE LIKELY THAT PRECIP
MAY BE A MIX OF FREEZING DRIZZLE/LGT-SNOW.
A WEAK THERMAL RIDGE TRIES TO PUSH OVERHEAD MON AFTN...AS LLVL FLOW
TURNS SOUTHWESTERLY. TEMPS SHUD HOVER ARND FREEZING...HOWEVER THIS
WILL HINGE ON CLOUD COVER ARRIVAL AND DEVELOPMENT OF PRECIP. IF THIS
IS DELAYED...TEMPS COULD PUSH A FEW DEGREES WARMER MON EARLY AFTN.
HEIGHTS SLOWLY INCREASE MON NGT...WITH THE MOISTURE PEELING EAST
ALONG WITH THE WEAKENING SHORTWAVE. AT THIS TIME HAVE MAINTAINED A
MENTION OF LGT SNOW OR PATCHY FREEZING DRIZZLE MON NGT...BUT COULD
END UP WITH A DRY PERIOD.
BEACHLER
&&
.LONG TERM...
206 PM CST
TUESDAY THROUGH SUNDAY...
TOWARDS THE MIDDLE OF THE WEEK ENSEMBLES MAINTAIN A HIGH CONFIDENCE
IN THE TROUGH ALONG THE SOUTHEAST CONUS WEAKENING WITH RIDGING
EXPANDING EAST ACROSS THE CENTRAL PLAINS. THIS SHUD PLACE THE BULK
OF THE REGION INTO A WEAK SFC RIDGE TUE/WED. WED AFTN THE SFC RIDGE
QUICKLY SLIDES SOUTHEAST...WHICH COULD ALLOW SOME WARM AIR TO ADVECT
NORTHEAST INTO THE CWFA AND PUSH SFC TEMPS CLOSE TO 40 DEG.
WITH A QUASI-ZONAL SETUP WED NGT/THUR...GUIDANCE SUGGESTS A ROBUST
MID-LVL VORT WILL QUICKLY SLIDE EAST FROM THE ROCKIES TOWARDS THE
PLAINS WED EVE. GUIDANCE THEN FURTHER STRENGTHENS THIS WAVE AND
LIFTS NORTHEAST ACROSS THE FORECAST AREA THUR. SOUNDINGS SUGGESTS
THAT PRECIP COULD START AS MAINLY RAIN WITH THIS SYSTEM...THEN
DYNAMICALLY COOL OVERNIGHT INTO THUR AND TRANSITION PRECIP OVER TO
LGT SNOW.
A RELATIVELY ACTIVE PATTERN CONTINUES TOWARDS THE END OF THE WEEK
INTO EARLY NEXT WEEKEND...WITH TEMPS GENERALLY IN THE UPR 20S/LOW
30S.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* MVFR CIGS UNTIL EARLY EVENING
* STRONG/GUSTY NORTHEAST WINDS UNTIL EARLY EVENING
* LIGHT SNOW LATE MONDAY AFTERNOON
IZZI
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE NEAR STL WILL SLOWLY TRACK EAST ACROSS THE OHIO
VALLEY THIS AFTERNOON INTO TONIGHT. AS IT DOES...LIGHT SNOW WILL
SLOWLY TAPER OFF TO FLURRIES. NORTHEAST WINDS OFF THE LAKE MAY
ALLOW SOME LIGHT SNOW SHOWERS TO CONTINUE NEAR THE LAKE BUT NOT
EXPECTING ANYTHING SIGNIFICANT. HAVE MAINTAINED MENTION OF VFR
LIGHT SNOW THROUGH EARLY EVENING THOUGH CONFIDENCE REGARDING END
TIME IS FAIRLY LOW. VISIBILITIES AND CIGS ARE SLOWLY TRENDING UP
AND THIS WILL CONTINUE THRU THE AFTERNOON WITH PREVAILING MVFR
EXPECTED. NORTHEAST WINDS WILL REMAIN STRONG AND GUSTY WITH GUSTS
INTO THE MID/UPPER 20 KT RANGE THROUGH LATE AFTERNOON WITH A SLOW
RELAXING OF THE SPEEDS/GUSTS THRU THE EVENING. A RIDGE AXIS WILL
MOVE ACROSS THE AREA TOWARD DAYBREAK WITH WINDS BECOMING LIGHT AND
VARIABLE AND THEN SWITCHING TO SOUTHERLY MID/LATE MONDAY MORNING.
A WEAK CLIPPER SYSTEM WILL MOVE SOUTHEAST ACROSS THE WESTERN LAKES
MONDAY AFTERNOON INTO MONDAY NIGHT AND WHILE THIS FEATURE HAS BEEN
CONSISTENT FOR A FEW DAYS...IT HAS LIMITED MOISTURE. HOWEVER...
THERE COULD BE A PERIOD OF LIGHT SNOW BY MID/LATE AFTERNOON ACROSS
NORTHERN IL THAT CONTINUES INTO MONDAY EVENING. THE CLOUD LAYERS
APPEAR DEEP ENOUGH FOR LIGHT SNOW BUT AS THE MID LEVELS DRY OUT IN
THE EVENING...PRECIP COULD TRANSITION TO LIGHT FREEZING DRIZZLE.
STILL SOME UNCERTAINTY HOW THIS PLAYS OUT...BUT OPTED TO INCLUDE A
PROB30 IN THE 30HR ORD TAF. CMS
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM FOR LIGHT SNOW MONDAY AFTERNOON...LOW FOR ASSOCIATED
CIGS/VIS.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...CHANCE LIGHT SNOW/MVFR.
TUESDAY...MVFR CIGS POSSIBLE.
WEDNESDAY...MAINLY VFR DURING THE DAY THEN CHANCE OF -RASN AND
MVFR/IFR AT NIGHT.
THURSDAY...CHANCE OF SNOW. MVFR/IFR POSSIBLE.
FRIDAY...CHANCE OF MVFR CIGS.
SATURDAY...CHANCE OF LIGHT SNOW/MVFR.
RATZER
&&
.MARINE...
131 PM CST
A QUICK MOVING CLIPPER SYSTEM...CURRENTLY CENTERED ACROSS SOUTHERN
ILLINOIS...WILL RAPIDLY SHIFT EASTWARD TOWARDS THE ATLANTIC COAST
BY MONDAY MORNING. NORTHEASTERLY WINDS OF 30-35 KT CONTINUE ACROSS
THE SOUTHERN 1/3RD OF LAKE MICHIGAN...AND THESE WINDS LOOK TO
CONTINUE FOR THE NEXT FEW HOURS...BEFORE A DIMINISHING TREND BEGINS
EARLY THIS EVENING. ANOTHER WEAKENING LOW WILL SHIFT SOUTHWARD JUST
WEST OF THE LAKE LATE MONDAY AND MONDAY NIGHT. THIS WILL RESULT IN A
PERIOD OF SOUTHERLY WINDS OVER THE LAKE DURING THIS PERIOD. LATER IN
THE WEEK ANOTHER LOW IS EXPECTED TO IMPACT THE GREAT LAKES REGION.
THIS SYSTEM STILL HAS THE POTENTIAL TO PRODUCE A PERIOD OF STRONG
SOUTHERLY WINDS LATE WEDNESDAY AND WEDNESDAY NIGHT...FOLLOWED BY A
PERIOD OF STRONG NORTHERLY WINDS THURSDAY INTO EARLY FRIDAY.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-LMZ743-
LMZ744-LMZ745-LMZ777-LMZ779-LMZ874-LMZ876-LMZ878 UNTIL 6 PM
SUNDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 9 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
240 PM CST Sun Jan 25 2015
.SHORT TERM...(Tonight)
ISSUED AT 239 PM CST SUN JAN 25 2015
Area of low pressure which has brought our precipitation was
centered near Carbondale early this afternoon. Rain/snow transition
line has been struggling to move any further south, and in fact
areas from Macomb to Bloomington which had switched over were
starting to mix with rain again. Temperatures have been above
freezing over most of the snow area and accumulations have been
minor and slushy, but some more substantial 1-2 inch totals have
occurred north of Galesburg where temperatures are now below
freezing. The deformation band of snow has been weakening some the
last few hours, and there is a substantial hole in the precip over
the central 2/3 of the forecast area.
The RAP model shows a further weakening of the the deformation band
over the next few hours, and actually has the entire CWA dry by 6
pm. Have some concerns that may be too quick across the southeast,
as the upper wave continues to dig across southeast Missouri, and
have lingered some likely PoP`s down there slightly beyond that time
frame, but reduced PoP`s to below 20% by 9 pm.
Overnight, models are trying to show some substantial clearing over
most of the forecast area beginning late evening. While there is
some breakup of the clouds upstream across Wisconsin, it is not
completely clear up there and the north/northeast flow is not
especially conducive to rapid clearing. Have gone with partly cloudy
skies overnight across the northwest half of the forecast area, but
clouds will already been increasing ahead of the next clipper which
will be dropping southeast into northern Minnesota overnight.
&&
.LONG TERM...(Monday through Sunday)
ISSUED AT 239 PM CST SUN JAN 25 2015
A couple of cooler days are on tap across central and southeast
Illinois in the wake of today`s clipper. There is still a chance we
may see a few snow flakes or sprinkles on Monday as a shearing
upper-level wave, currently diving across the Canadian Prairies,
passes through the Great Lakes region and parts of the Midwest.
However, looking at forecast soundings, there will be a very small
window of opportunity where ice crystals will be present, suggesting
the chance of measurable precipitation is quite low. So, for now,
will only carry a chance of flurries Monday across the northern
portion of the forecast area as the very sheared wave passes to our
north. It is definitely possible that we will see nothing at all, or
perhaps some light drizzle or freezing drizzle (depending on surface
temperatures) due to the paucity of ice crystals.
Temperatures will warm heading into midweek as the persistent
amplified upper-level flow briefly turns more zonal, and a system
approaches from the Pacific coast. This system will mainly pose a
rain threat as it moves through Wednesday night into Thursday. A
brief period of snow is not out of the question later Thursday as
cold air filters in behind the system, but forecast soundings
currently suggest the moisture depth will be too shallow to support
precipitation (no ice crystals) by the time the thermal profile
would support snow.
Another cool down is expected in the wake of the midweek system, but
temperatures should still be near normal for late January. The
eastern North American mean trof that has been in place will try to
reestablish itself by the weekend. A clipper type wave in the
returning northwest upper-level flow may bring a chance of snow to
the area over the weekend. However, the current storm track keeps
the best snow chances to our north, and have only included a slight
chance of snow at this time.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1128 AM CST SUN JAN 25 2015
Several challenges with this TAF set. Widespread precipitation
north of a KIJX-KDNV line has been changing from rain to snow.
Radar data indicates the transition line is just south of KBMI to
about 30SW KPIA, although a bit of mixed precipitation has also
been reported near KCMI. Still seeing temperatures in the upper
30s to lower 40s from KSPI-KCMI so the transition is still a
couple hours away. High-resolution model data suggests some
erosion in the precip shield as the afternoon goes on, as a
surface low travels through the southern tip of the state, so most
of the TAF sites should see the precip end by 00Z. Strong
northeast winds kicking in on the north flank of the low
circulation, so winds 25-30 knots will be spreading over the TAF
sites over the next couple hours and persist much of the evening.
IFR/LIFR conditions will be occurring as the snow moves through.
Some improvement expected this evening, but have largely kept MVFR
ceilings at all TAF sites through the night, as the wind flow does
not favor rapid clearing. Did scatter out KPIA for a time after
06Z, as suggested by a narrow clear slot on the RAP model. Winds
to turn more southwesterly Monday morning ahead of a storm system
which will pass to our north.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Bak
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1158 AM CST SUN JAN 25 2015
.SHORT TERM...
329 AM CST
THROUGH TONIGHT...
HAVE FURTHERED THE DIMINISHING SNOWFALL TREND IN THE FORECAST FOR
TODAY...MAINLY NORTH OF INTERSTATE 80. ACROSS THE ENTIRE AREA THIS
LOOKS TO BE A MAINLY LOW IMPACT...NUISANCE TYPE SNOW...WITH SOME
COMMUNITIES IN THE NORTH QUITE POSSIBLY NOT SEEING ANY
ACCUMULATION. HAVE CONTINUED A SPECIAL WEATHER STATEMENT FOR AREAS
ALONG AND SOUTH OF I-80.
SATELLITE IMAGERY THIS MORNING DEPICTS THE CLOSED UPPER CIRCULATION
ACROSS WESTERN IA WITH AN AREA OF COOLING CLOUD TOPS IN ADVANCE OF
THIS MOVING INTO NORTHWEST IL. THIS IS CORRELATING WITH MAINLY LIGHT
RAIN OR RAIN/SNOW MIX IN THE SMALL WINDOW OF DEEPER MOIST
ADVECTION AHEAD OF THE LOW. SIMPLE EXTRAPOLATION OF THE CURRENT
AREA OF PRECIP IN IOWA AND THE DEVELOPING DEFORMATION ON THE
BACKSIDE CLEARLY INDICATE THE SOUTHERN CWA IS MORE SUPPORTED FOR
PRECIPITATION THAN THE NORTH. AT THE SURFACE...TEMPERATURES ARE
AROUND OR JUST ABOVE FREEZING ACROSS MUCH OF THE FORECAST AREA. A
DEVELOPING COLD FRONT IS ADVANCING SOUTHWARD INTO NORTHERN IL WITH
DEW POINTS IN THE MID TO UPPER 20S NORTH OF THIS FEATURE...ANOTHER
HINDRANCE OF APPRECIABLE PRECIPITATION IN NORTHERN AREAS OF THE
FORECAST AREA.
SHORT RANGE GUIDANCE LIKE ITS LONG RANGE COUNTERPARTS THE PAST
SEVERAL DAYS SHOW A FAIR AMOUNT OF DISCREPANCY...NAMELY ON COVERAGE
OF PRECIP TODAY AND PRECIP TYPE IN THE SOUTHERN CWA THIS
MORNING...BUT THEY LEND SUPPORT TO THE OBSERVATIONAL TRENDS. AS
THE AREA OF RAIN ASSOCIATED WITH ELEVATED ISENTROPIC ASCENT MOVES
INTO THE SOUTHERN FORECAST AREA...PROFILES SUPPORT A PERIOD OF
RAIN OR MIX INITIALLY...AND SOME LOCATIONS MIGHT HAVE AIR
TEMPERATURES RIGHT AT FREEZING. WOULD EXPECT ANY FREEZING RAIN
THREAT TO BE SHORT LIVED AS PROFILES TREND TOWARD SNOW. MESOSCALE
CONVERGENCE AND BAROCLINIC FORCING FOR INDUCED LIFT WOULD BECOME
MORE FAVORED JUST TO THE NORTHEAST OF THE CLOSED 850MB
CIRCULATION AS IT PIVOTS MORE EASTWARD. THAT IS FAVORED ACROSS
THE SOUTHERN TIER OR TWO OF COUNTIES LATER THIS MORNING INTO
EARLY AFTERNOON. PROFILES ARE MILD FOR IDEAL SNOW GROWTH...AND
MAYBE EVEN FOR SNOW AT ALL DOWN TOWARD GIBSON CITY FOR MUCH OF THE
MORNING. HAVE SNOW TOTALS AROUND ONE TO TWO INCHES FROM PERU TO
RENSSELAER AND SOUTHWARD FOR TODAY...WITH SNOW DEPARTING NEAR OR
SOON AFTER SUNDOWN.
AS FOR AREAS NORTH OF INTERSTATE 80...SHOULD SEE A GRADUAL INCREASE
IN LIGHT SNOW AREAWIDE BY MID-MORNING. DRY CORRIDOR NEAR 850MB
SEEN ON EARLY MORNING AMDAR SOUNDINGS OVER CHICAGO SHOULD LIMIT
INTENSITY OF ANY SNOW IN THE NORTHERN FORECAST AREA...AS WILL JUST
LESS FORCING. AREAS OF NORTHEAST ILLINOIS STILL LOOK TO HAVE
ONSHORE FLOW BEHIND THE COLD FRONT...BUT FORECAST INVERSION
HEIGHTS AS WELL AS ADAPTED ONES FROM THE 00Z GRB RAOB LAST
EVE...INDICATE VERY MARGINAL DEPTH OF CONVECTIVE CLOUDS. THUS NOT
EXPECTING MUCH IF ANY ENHANCEMENT TO ALREADY MINIMAL SYNOPTIC
FORCING OVER NORTHEAST IL. COULD SEE SOME DISORGANIZED LIGHT SNOW
OR FLURRIES LATE THIS AFTERNOON INTO THIS EVENING AS PROFILES OF
THE LAKE INDUCED STRATOCU COOL INTO THE ICE INITIATION LAYER...BUT
THIS SHOULD NOT BE A BIG DEAL.
AREAWIDE THE NORTHEAST WINDS WILL INCREASE TO 30 MPH AND MAYBE EVEN
A LITTLE HIGHER JUST OF THE LAKE. WITH MINIMAL SNOW NORTH NOT
EXPECTING ANY BLOWING SNOW ISSUES...AND SOUTH THE LOW SNOW-TO-
LIQUID RATIOS SHOULD SUPPRESS MUCH FOR BLOWING ISSUES...THOUGH
COULD LEAD TO MORE REDUCED VISIBILITY DURING THE TIME OF FALLING
SNOW THIS AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
MONDAY THROUGH SATURDAY...
THE DISTURBED FLOW PATTERN WILL TURN MORE NORTHWESTERLY MONDAY AND
TUESDAY AS A MAJOR SYSTEM IS EXPECTED TO DEVELOP OFF THE NORTHEAST
COAST. GIVEN THIS POSSIBLY LEADING TO A SLOWER PATTERN...AS WELL
AS THE TREND OF TODAYS SYSTEM...IT IS QUITE CONCEIVABLE THAT THE
NEXT DISTURBANCE FOR MONDAY AFTERNOON AND NIGHT TRENDS WEST AS
WELL...WHICH THE EC HAS HAD IN ITS SOLUTION FOR THREE CONSECUTIVE
RUNS. THIS SYSTEM THOUGH IS NOT AS STRONG AS TODAYS AS IT IS MORE
OF A SHEARED AREA OF VORTICITY ALONG THE LINGERING BAROCLINIC
ZONE. FORCING FOR PRECIP LOOKS PRETTY LIGHT ONCE AGAIN MONDAY
AFTERNOON AND NIGHT BUT ENOUGH TO GO A LITTLE HIGHER ON POPS FOR
NORTHERN PARTS OF THE FORECAST AREA. RIGHT NOW GUIDANCE IS IN
DECENT AGREEMENT WITH SATURATING DEEP ENOUGH FOR PRECIP TYPE TO BE
LIGHT SNOW IF IT CAN OCCUR...BUT NEED TO KEEP AN EYE OUT FOR SOME
FREEZING DRIZZLE POTENTIAL IN THESE LIGHT ASCENT SITUATIONS.
A SLOW MODERATION LOOKS TO OCCUR TUESDAY INTO WEDNESDAY AND THIS
COULD BE VERY MINIMAL DEPENDING ON CLOUD COVER WHICH REMAINS A BIG
QUESTION MARK. HAVE LEANED MORE CLOUDY TUESDAY BUT STILL THINK
WITH A WESTERLY PUSH WEDNESDAY WOULD HAVE SUN POTENTIAL. LONG
RANGE GUIDANCE INDICATES A PACIFIC SYSTEM TO BE THE NEXT ONE TO
POSSIBLY BRING PRECIPITATION TO THE AREA WEDNESDAY NIGHT INTO
THURSDAY. CONTINUE POPS DURING THIS TIME FRAME AND AT THIS POINT
PROFILES ARE NEAR THE BORDER FOR RAIN OR SNOW...SO DID NOT GET TOO
FANCY WITH THE FORECAST PRECIPITATION TYPE. BEHIND THIS SYSTEM IT
SEEMS FAVORED FOR TEMPERATURES TO COOL SOME DURING THE LATTER
HALF OF THE WEEK...TO SLIGHTLY BELOW NORMAL VALUES. OBVIOUSLY ANY
FRESH SNOW COVER WOULD HELP LEAN THAT MORE TOWARD BELOW NORMAL.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* LIGHT SNOW TAPERING TO FLURRIES THIS AFTERNOON.
* MVFR CIGS LIFTING THIS AFTERNOON THEN SCATTERING OUT TONIGHT.
* STRONG/GUSTY NORTHEAST WINDS THRU MID EVENING.
* LIGHT SNOW LATE MONDAY AFTERNOON. CMS
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE NEAR STL WILL SLOWLY TRACK EAST ACROSS THE OHIO
VALLEY THIS AFTERNOON INTO TONIGHT. AS IT DOES...LIGHT SNOW WILL
SLOWLY TAPER OFF TO FLURRIES. NORTHEAST WINDS OFF THE LAKE MAY
ALLOW SOME LIGHT SNOW SHOWERS TO CONTINUE NEAR THE LAKE BUT NOT
EXPECTING ANYTHING SIGNIFICANT. HAVE MAINTAINED MENTION OF VFR
LIGHT SNOW THROUGH EARLY EVENING THOUGH CONFIDENCE REGARDING END
TIME IS FAIRLY LOW. VISIBILITIES AND CIGS ARE SLOWLY TRENDING UP
AND THIS WILL CONTINUE THRU THE AFTERNOON WITH PREVAILING MVFR
EXPECTED. NORTHEAST WINDS WILL REMAIN STRONG AND GUSTY WITH GUSTS
INTO THE MID/UPPER 20 KT RANGE THROUGH LATE AFTERNOON WITH A SLOW
RELAXING OF THE SPEEDS/GUSTS THRU THE EVENING. A RIDGE AXIS WILL
MOVE ACROSS THE AREA TOWARD DAYBREAK WITH WINDS BECOMING LIGHT AND
VARIABLE AND THEN SWITCHING TO SOUTHERLY MID/LATE MONDAY MORNING.
A WEAK CLIPPER SYSTEM WILL MOVE SOUTHEAST ACROSS THE WESTERN LAKES
MONDAY AFTERNOON INTO MONDAY NIGHT AND WHILE THIS FEATURE HAS BEEN
CONSISTENT FOR A FEW DAYS...IT HAS LIMITED MOISTURE. HOWEVER...
THERE COULD BE A PERIOD OF LIGHT SNOW BY MID/LATE AFTERNOON ACROSS
NORTHERN IL THAT CONTINUES INTO MONDAY EVENING. THE CLOUD LAYERS
APPEAR DEEP ENOUGH FOR LIGHT SNOW BUT AS THE MID LEVELS DRY OUT IN
THE EVENING...PRECIP COULD TRANSITION TO LIGHT FREEZING DRIZZLE.
STILL SOME UNCERTAINTY HOW THIS PLAYS OUT...BUT OPTED TO INCLUDE A
PROB30 IN THE 30HR ORD TAF. CMS
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH FOR LIGHT SNOW TAPERING TO FLURRIES THIS AFTERNOON...LOW
FOR SPECIFIC TIMING AND ASSOCIATED CIGS/VIS.
* MEDIUM FOR CIGS THRU THE PERIOD.
* HIGH FOR WINDS THRU THE PERIOD.
* MEDIUM FOR LIGHT SNOW MONDAY AFTERNOON...LOW FOR ASSOCIATED
CIGS/VIS. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...CHANCE LIGHT SNOW/MVFR.
TUESDAY...MVFR CIGS POSSIBLE.
WEDNESDAY...MAINLY VFR DURING THE DAY THEN CHANCE OF -RASN AND
MVFR/IFR AT NIGHT.
THURSDAY...CHANCE OF SNOW. MVFR/IFR POSSIBLE.
FRIDAY...CHANCE OF MVFR CIGS.
SATURDAY...CHANCE OF LIGHT SNOW/MVFR.
RATZER
&&
.MARINE...
137 AM CST
MAIN MARINE FORECAST FOCUS CONTINUES TO BE A PERIOD OF STRONG
NORTHEAST WINDS ACROSS THE SOUTHERN 2/3 OR SO OF LAKE MICHIGAN
THROUGH THIS EVENING.
A COLD FRONT HAS PUSHED SOUTH ACROSS MUCH OF LAKE MICHIGAN SINCE
SATURDAY MORNING...WITH COLD HIGH PRESSURE SPREADING ACROSS
MANITOBA...WESTERN ONTARIO AND THE NORTHERN LAKES. EARLY THIS
MORNING AN AREA OF LOW PRESSURE WAS OVER IOWA...AND THIS LOW WILL
MOVE QUICKLY SOUTHEAST TO THE LOWER OHIO VALLEY BY THIS EVENING.
THIS LOW AND THE HIGH PRESSURE TO THE NORTH OF THE LAKES WILL
COMBINE TO RAPIDLY TIGHTEN THE SURFACE PRESSURE GRADIENT ACROSS THE
LAKE THIS MORNING...WITH NORTH-NORTHEAST WINDS INCREASING TO 25-30
KT. RECENT OBSERVATION PLATFORMS ALONG THE WEST SHORE OF THE LAKE
HAVE BEEN GUSTING 26-27 KTS BEHIND THE COLD FRONT AS FAR SOUTH AS
MILWAUKEE. THESE STRONGER WINDS WILL CONTINUE TO DEVELOP SOUTHWARD
DOWN THE REMAINDER OF THE LAKE THIS MORNING. FORECAST SOUNDINGS
INDICATE WINDS TO 30 KT WILL BE PREVALENT THROUGH THE DAY...WITH A
FEW GALE FORCE GUSTS TO 35 KT POSSIBLE. WINDS WILL REMAIN GUSTY INTO
THE EVENING HOURS ACROSS THE FAR SOUTHERN PORTION OF THE LAKE...BUT
WILL DIMINISH RAPIDLY FROM THE NORTH AS A WEAK RIDGE OF HIGH
PRESSURE SPREADS IN BEHIND THE QUICK MOVING LOW WHICH MOVE TO THE
CAROLINA COAST BY MONDAY MORNING.
THE WEAK RIDGE WILL MOVE QUICKLY SOUTHEAST OF THE LAKE MONDAY...
WITH WINDS BRIEFLY BECOMING SOUTHERLY AND INCREASING BACK AROUND 20
KT OR SO AHEAD OF ANOTHER LOW PRESSURE SYSTEM WHICH WILL DROP
SOUTHEAST ACROSS THE LAKE MONDAY NIGHT...WHILE FILLING. WEAK
GRADIENT CONDITIONS WILL THEN LINGER ACROSS THE LAKE TUESDAY AND
TUESDAY NIGHT AS THE TROUGH FILLS AND A WEAK RIDGE MOVES ACROSS THE
REGION. INDICATIONS ARE THAT ANOTHER LOW WILL DEVELOP ACROSS THE
PLAINS MID-WEEK...AND WILL APPROACH THE LAKE FROM THE WEST LATE
WEDNESDAY. THIS MAY RESULT IN A BRIEF PERIOD OF ENHANCED
EAST-SOUTHEAST WINDS LATE WEDNESDAY OR WEDNESDAY NIGHT...WITH A
PERIOD OF GUSTY NORTHERLY WINDS POSSIBLE THURSDAY AS THE LOW MOVES
EAST OF THE LAKE.
FOR THE IL/NORTHWEST INDIANA NEARSHORE AREA...SMALL CRAFT ADVISORY
IS IN EFFECT FROM 6 AM CST THIS MORNING AS WINDS/WAVES QUICKLY
INCREASE AND BUILD. ADVISORY HEADLINE WILL REMAIN IN EFFECT THROUGH
MID-MORNING MONDAY...AS WAVES SLOWLY SUBSIDE BELOW 4 FT.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-
LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 6 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...6 PM SUNDAY TO 9 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1128 AM CST Sun Jan 25 2015
.UPDATE...
ISSUED AT 1015 AM CST SUN JAN 25 2015
Surface low located just northwest of St. Louis late this morning.
Widespread precipitation continues over our northern CWA in the
deformation zone, with dual-pol radar data from showing the
rain/snow line roughly along a Canton to Lexington line, although
some mixed precipitation is showing up in the latest observation
from Champaign. Freezing level will continue to lower as the low
tracks toward Carbondale by midday, bringing the rain/snow line
closer to Springfield by early afternoon, where temperatures are
still currently in the lower 40s.
Will need to watch snow rates across the north closely. Already
have had 1 inch reported just northeast of Galesburg where light
to moderate snow continues. NOAA Satellite Analysis Branch shows
this area on the periphery of an area of enhanced snow production
over the next few hours, although drier air is being advected in
from the northeast where dew points in north central Illinois are
down to the low-mid 20s.
Have sent some updated zones/grids to update the precipitation and
transition trends, and to tweak the hourly temperatures especially
across the northern CWA.
&&
.SHORT TERM...(Today)
ISSUED AT 453 AM CST SUN JAN 25 2015
3am surface analysis has low pressure centered over southern Iowa
with the latest 3 hourly surface pressure falls suggesting a
continued southeast movement to the low this morning. Not a lot
of cold air associated with this particular storm system as surface
temperatures across Iowa, southern Minnesota and southeast South
Dakota were still above freezing after the low shifted away from
there area.
By 12z, the low is forecast by most models to be just west-southwest
of Quincy. Temperatures ahead of the low continue to slowly rise
early this morning with readings ranging from the mid 30s over far
eastern Illinois to the middle 40s over southwest Illinois. With the
low expected to push to near Lawrenceville by late this afternoon,
we expect the warmest temperatures across the north this morning
with steady or slowly falling temperatures this afternoon as winds
turn into the northeast and increase to between 15 and 25 mph with
gusts up to 30 mph at times.
The high resolution short term forecast soundings continue to show
temperatures at the surface too warm to support much in the way of
snow until later this morning across the north, and not until later
this afternoon over central through east central Illinois. Further
south, any changeover looks to hold off until the low shifts to
the south of the area this evening. Am a bit concerned with our
northern counties...roughly along and north of I-74...later this
morning and especially this afternoon when the low shifts further
to our southwest, surface winds up to 900 mb switch into the northeast
with soundings showing 30-40 kts around 900 mb. That may be enough
to bring surface temps down sufficiently for a brief period of time
for a period of moderate snowfall before soundings indicate we lose
the ice crystals in the upper layers of the clouds. However, except
for the NAM, which once again appears to have initialized too cold
in the lower levels of the atmosphere, all other forecast soundings
indicate surface temperatures should stay above freezing during the
daylight hours. Highest totals, in the 1 to 2 inch range will be
along and north of the I-74 corridor with lighter accumulations
to the south.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 453 AM CST SUN JAN 25 2015
Surface low pressure between Evansville and Louisville KY at sunset
and then into eastern KY by midnight tonight. Have increase chances
of mixed precipitation to likely over southeast IL during first half
of evening, as light rain changes to light snow before diminishing
during late evening. Snowfall amounts in southeast IL should be less
than a half inch. Gusty NNE winds linger during the evening before
diminishing overnight as low pressure pulls away from IL with weak
ridging into IL by dawn Monday. Lows tonight in the upper teens to
near 20F north and mid 20s south of I-70 in southeast IL.
Another clipper low pressure system will dive quickly southeast into
the upper MS river valley by sunset Monday, though this time best
chances of light snow to be NE of central IL Monday afternoon and
Monday night. Carried slight chances of light snow and flurries over
northern and NE counties Monday afternoon into Monday night. Highs
Monday range from lower 30s from Bloomington and Champaign NE to
near 40F from Jacksonville SW.
1025 mb surface high pressure drifts over IL Tue night and into the
eastern Ohio river valley Wed while upper level ridge noses into IL.
This to bring quiet weather with temps moderating again with highs
in the mid 30s to lower 40s Tue and 40s Wed and near 50F from
Jacksonville SW.
Low pressure off the Pacific northwest moves east into IL and Ohio
river valley Wed night and Thu returning a chance of mainly light
rain, though could be a mix of light snow northern counties before
ending. Highs Thu around 40F northern areas and mid 40s in southeast
IL. Cooler highs in the mid to upper 30s Friday which is close to
normal for late January. Extended models dig an upper level trof
over the Great Lakes and eastern states next weekend bringing
chances of light snow showers especially NE areas. Temps also cool
some more Sat night and Sunday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1128 AM CST SUN JAN 25 2015
Several challenges with this TAF set. Widespread precipitation
north of a KIJX-KDNV line has been changing from rain to snow.
Radar data indicates the transition line is just south of KBMI to
about 30SW KPIA, although a bit of mixed precipitation has also
been reported near KCMI. Still seeing temperatures in the upper
30s to lower 40s from KSPI-KCMI so the transition is still a
couple hours away. High-resolution model data suggests some
erosion in the precip shield as the afternoon goes on, as a
surface low travels through the southern tip of the state, so most
of the TAF sites should see the precip end by 00Z. Strong
northeast winds kicking in on the north flank of the low
circulation, so winds 25-30 knots will be spreading over the TAF
sites over the next couple hours and persist much of the evening.
IFR/LIFR conditions will be occurring as the snow moves through.
Some improvement expected this evening, but have largely kept MVFR
ceilings at all TAF sites through the night, as the wind flow does
not favor rapid clearing. Did scatter out KPIA for a time after
06Z, as suggested by a narrow clear slot on the RAP model. Winds
to turn more southwesterly Monday morning ahead of a storm system
which will pass to our north.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Smith
LONG TERM...07
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1005 AM CST SUN JAN 25 2015
.SHORT TERM...
329 AM CST
THROUGH TONIGHT...
HAVE FURTHERED THE DIMINISHING SNOWFALL TREND IN THE FORECAST FOR
TODAY...MAINLY NORTH OF INTERSTATE 80. ACROSS THE ENTIRE AREA THIS
LOOKS TO BE A MAINLY LOW IMPACT...NUISANCE TYPE SNOW...WITH SOME
COMMUNITIES IN THE NORTH QUITE POSSIBLY NOT SEEING ANY
ACCUMULATION. HAVE CONTINUED A SPECIAL WEATHER STATEMENT FOR AREAS
ALONG AND SOUTH OF I-80.
SATELLITE IMAGERY THIS MORNING DEPICTS THE CLOSED UPPER CIRCULATION
ACROSS WESTERN IA WITH AN AREA OF COOLING CLOUD TOPS IN ADVANCE OF
THIS MOVING INTO NORTHWEST IL. THIS IS CORRELATING WITH MAINLY LIGHT
RAIN OR RAIN/SNOW MIX IN THE SMALL WINDOW OF DEEPER MOIST
ADVECTION AHEAD OF THE LOW. SIMPLE EXTRAPOLATION OF THE CURRENT
AREA OF PRECIP IN IOWA AND THE DEVELOPING DEFORMATION ON THE
BACKSIDE CLEARLY INDICATE THE SOUTHERN CWA IS MORE SUPPORTED FOR
PRECIPITATION THAN THE NORTH. AT THE SURFACE...TEMPERATURES ARE
AROUND OR JUST ABOVE FREEZING ACROSS MUCH OF THE FORECAST AREA. A
DEVELOPING COLD FRONT IS ADVANCING SOUTHWARD INTO NORTHERN IL WITH
DEW POINTS IN THE MID TO UPPER 20S NORTH OF THIS FEATURE...ANOTHER
HINDRANCE OF APPRECIABLE PRECIPITATION IN NORTHERN AREAS OF THE
FORECAST AREA.
SHORT RANGE GUIDANCE LIKE ITS LONG RANGE COUNTERPARTS THE PAST
SEVERAL DAYS SHOW A FAIR AMOUNT OF DISCREPANCY...NAMELY ON COVERAGE
OF PRECIP TODAY AND PRECIP TYPE IN THE SOUTHERN CWA THIS
MORNING...BUT THEY LEND SUPPORT TO THE OBSERVATIONAL TRENDS. AS
THE AREA OF RAIN ASSOCIATED WITH ELEVATED ISENTROPIC ASCENT MOVES
INTO THE SOUTHERN FORECAST AREA...PROFILES SUPPORT A PERIOD OF
RAIN OR MIX INITIALLY...AND SOME LOCATIONS MIGHT HAVE AIR
TEMPERATURES RIGHT AT FREEZING. WOULD EXPECT ANY FREEZING RAIN
THREAT TO BE SHORT LIVED AS PROFILES TREND TOWARD SNOW. MESOSCALE
CONVERGENCE AND BAROCLINIC FORCING FOR INDUCED LIFT WOULD BECOME
MORE FAVORED JUST TO THE NORTHEAST OF THE CLOSED 850MB
CIRCULATION AS IT PIVOTS MORE EASTWARD. THAT IS FAVORED ACROSS
THE SOUTHERN TIER OR TWO OF COUNTIES LATER THIS MORNING INTO
EARLY AFTERNOON. PROFILES ARE MILD FOR IDEAL SNOW GROWTH...AND
MAYBE EVEN FOR SNOW AT ALL DOWN TOWARD GIBSON CITY FOR MUCH OF THE
MORNING. HAVE SNOW TOTALS AROUND ONE TO TWO INCHES FROM PERU TO
RENSSELAER AND SOUTHWARD FOR TODAY...WITH SNOW DEPARTING NEAR OR
SOON AFTER SUNDOWN.
AS FOR AREAS NORTH OF INTERSTATE 80...SHOULD SEE A GRADUAL INCREASE
IN LIGHT SNOW AREAWIDE BY MID-MORNING. DRY CORRIDOR NEAR 850MB
SEEN ON EARLY MORNING AMDAR SOUNDINGS OVER CHICAGO SHOULD LIMIT
INTENSITY OF ANY SNOW IN THE NORTHERN FORECAST AREA...AS WILL JUST
LESS FORCING. AREAS OF NORTHEAST ILLINOIS STILL LOOK TO HAVE
ONSHORE FLOW BEHIND THE COLD FRONT...BUT FORECAST INVERSION
HEIGHTS AS WELL AS ADAPTED ONES FROM THE 00Z GRB RAOB LAST
EVE...INDICATE VERY MARGINAL DEPTH OF CONVECTIVE CLOUDS. THUS NOT
EXPECTING MUCH IF ANY ENHANCEMENT TO ALREADY MINIMAL SYNOPTIC
FORCING OVER NORTHEAST IL. COULD SEE SOME DISORGANIZED LIGHT SNOW
OR FLURRIES LATE THIS AFTERNOON INTO THIS EVENING AS PROFILES OF
THE LAKE INDUCED STRATOCU COOL INTO THE ICE INITIATION LAYER...BUT
THIS SHOULD NOT BE A BIG DEAL.
AREAWIDE THE NORTHEAST WINDS WILL INCREASE TO 30 MPH AND MAYBE EVEN
A LITTLE HIGHER JUST OF THE LAKE. WITH MINIMAL SNOW NORTH NOT
EXPECTING ANY BLOWING SNOW ISSUES...AND SOUTH THE LOW SNOW-TO-
LIQUID RATIOS SHOULD SUPPRESS MUCH FOR BLOWING ISSUES...THOUGH
COULD LEAD TO MORE REDUCED VISIBILITY DURING THE TIME OF FALLING
SNOW THIS AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
MONDAY THROUGH SATURDAY...
THE DISTURBED FLOW PATTERN WILL TURN MORE NORTHWESTERLY MONDAY AND
TUESDAY AS A MAJOR SYSTEM IS EXPECTED TO DEVELOP OFF THE NORTHEAST
COAST. GIVEN THIS POSSIBLY LEADING TO A SLOWER PATTERN...AS WELL
AS THE TREND OF TODAYS SYSTEM...IT IS QUITE CONCEIVABLE THAT THE
NEXT DISTURBANCE FOR MONDAY AFTERNOON AND NIGHT TRENDS WEST AS
WELL...WHICH THE EC HAS HAD IN ITS SOLUTION FOR THREE CONSECUTIVE
RUNS. THIS SYSTEM THOUGH IS NOT AS STRONG AS TODAYS AS IT IS MORE
OF A SHEARED AREA OF VORTICITY ALONG THE LINGERING BAROCLINIC
ZONE. FORCING FOR PRECIP LOOKS PRETTY LIGHT ONCE AGAIN MONDAY
AFTERNOON AND NIGHT BUT ENOUGH TO GO A LITTLE HIGHER ON POPS FOR
NORTHERN PARTS OF THE FORECAST AREA. RIGHT NOW GUIDANCE IS IN
DECENT AGREEMENT WITH SATURATING DEEP ENOUGH FOR PRECIP TYPE TO BE
LIGHT SNOW IF IT CAN OCCUR...BUT NEED TO KEEP AN EYE OUT FOR SOME
FREEZING DRIZZLE POTENTIAL IN THESE LIGHT ASCENT SITUATIONS.
A SLOW MODERATION LOOKS TO OCCUR TUESDAY INTO WEDNESDAY AND THIS
COULD BE VERY MINIMAL DEPENDING ON CLOUD COVER WHICH REMAINS A BIG
QUESTION MARK. HAVE LEANED MORE CLOUDY TUESDAY BUT STILL THINK
WITH A WESTERLY PUSH WEDNESDAY WOULD HAVE SUN POTENTIAL. LONG
RANGE GUIDANCE INDICATES A PACIFIC SYSTEM TO BE THE NEXT ONE TO
POSSIBLY BRING PRECIPITATION TO THE AREA WEDNESDAY NIGHT INTO
THURSDAY. CONTINUE POPS DURING THIS TIME FRAME AND AT THIS POINT
PROFILES ARE NEAR THE BORDER FOR RAIN OR SNOW...SO DID NOT GET TOO
FANCY WITH THE FORECAST PRECIPITATION TYPE. BEHIND THIS SYSTEM IT
SEEMS FAVORED FOR TEMPERATURES TO COOL SOME DURING THE LATTER
HALF OF THE WEEK...TO SLIGHTLY BELOW NORMAL VALUES. OBVIOUSLY ANY
FRESH SNOW COVER WOULD HELP LEAN THAT MORE TOWARD BELOW NORMAL.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* LIGHT SNOW THROUGH THIS AFTERNOON.
* IFR CIGS LIFTING TO MVFR BY THIS AFTERNOON...THEN SCATTERING OUT
TONIGHT.
* STRONG/GUSTY NORTHEAST WINDS THRU MID EVENING. CMS
//DISCUSSION...UPDATED 14Z...
LOW PRESSURE OVER NORTHEAST MISSOURI WILL MOVE ACROSS THE OHIO
VALLEY TONIGHT. NORTHEAST WINDS WILL REMAIN STRONG AND GUSTY THRU
THIS EVENING WITH GUSTS IN THE MID/UPPER 20KT RANGE. HEAVIEST
PRECIP SHOULD REMAIN ALONG AND SOUTH OF I-80 WITH LIGHTER AMOUNTS
NORTH. MANY AREAS REPORTING LIGHT SNOW BUT STILL SOME MIXED RAIN
AT MDW AND GYY...WHICH SHOULD TRANSITION TO SNOW BY LATE MORNING.
CMS
PREVIOUS 12Z DISCUSSION...
WEAK COLD FRONTAL BOUNDARY HAS SAGGED INTO NORTHEAST ILLINOIS
EARLY THIS MORNING...WITH IFR/LIFR CIGS NOTED IN THE VICINITY OF
THE FRONTAL BOUNDARY. EXPECT THE LIFR CIGS TO BE SOMEWHAT SHORT-
LIVED HOWEVER...AS WINDS RAMP UP FROM THE NORTHEAST.
RADAR CLEARLY SHOWS CIRCULATION WITH ALBERTA CLIPPER DROPPING
SOUTHEAST ACROSS IA...WITH EXPANSION OF WEAK RETURNS OVER NORTHERN
ILLINOIS AND A FEW REPORTS OF LIGHT SNOW BEGINNING TO REACH THE
GROUND. HIGH-RES HRRR HAS BEEN FAIRLY CONSISTENT IN BRINING NORTH
EDGE OF MORE ORGANIZED SNOW BAND ACROSS THE TERMINALS THIS MORNING
INTO MIDDAY/EARLY AFTERNOON...AND IS EXPECTED TO PRODUCE A PERIOD
OF LIGHT ACCUMULATING SNOW WITH OCCASIONAL IFR VSBYS. SNOW SHOULD
TAPER OFF TO LIGHT SNOW SHOWERS/FLURRIES THIS AFTERNOON WITH CIGS
RISING TO MVFR.
AS INDICATED ABOVE...STRONG/GUSTY NORTHEAST WINDS ARE ALREADY
RAMPING UP EARLY THIS MORNING WITH GUSTS 20-30 KT ALREAD ACROSS
FAR NORTHERN IL. 040-060 DEG WINDS NEAR 20 KT WITH GUSTS NEAR 30
KT ARE EXPECTED TO CONTIUNE INTO THE AFTERNOON BEFORE SLOW DECLINE
IN WIND SPEEDS AND A GRADUAL BACKING TO THE NORTH OCCURS. WINDS
WILL DIMINISH MORE QUICKLY TONIGHT...AS A WEAK HIGH PRESSURE RIDGE
BUILDS IN FROM THE NORTHWEST. THIS SHOULD ALLOW LOWER CLOUDS TO
SCATTER OUT OVERNIGHT.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH FOR LIGHT SNOW...MEDIUM FOR DURATION/END TIME THIS
AFTERNOON OR EARLY THIS EVENING.
* HIGH FOR CIGS THRU THIS AFTERNOON...THEN MEDIUM FOR THE REST OF
THE PERIOD.
* HIGH FOR WIND SPEEDS/GUSTS/DIRECTIONS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...CHANCE LIGHT SNOW/MVFR.
TUESDAY...MVFR CIGS POSSIBLE.
WEDNESDAY...MAINLY VFR DURING THE DAY THEN CHANCE OF -RASN AND
MVFR/IFR AT NIGHT.
THURSDAY...CHANCE OF SNOW. MVFR/IFR POSSIBLE.
FRIDAY...CHANCE OF MVFR CIGS.
SATURDAY...CHANCE OF LIGHT SNOW/MVFR.
RATZER
&&
.MARINE...
137 AM CST
MAIN MARINE FORECAST FOCUS CONTINUES TO BE A PERIOD OF STRONG
NORTHEAST WINDS ACROSS THE SOUTHERN 2/3 OR SO OF LAKE MICHIGAN
THROUGH THIS EVENING.
A COLD FRONT HAS PUSHED SOUTH ACROSS MUCH OF LAKE MICHIGAN SINCE
SATURDAY MORNING...WITH COLD HIGH PRESSURE SPREADING ACROSS
MANITOBA...WESTERN ONTARIO AND THE NORTHERN LAKES. EARLY THIS
MORNING AN AREA OF LOW PRESSURE WAS OVER IOWA...AND THIS LOW WILL
MOVE QUICKLY SOUTHEAST TO THE LOWER OHIO VALLEY BY THIS EVENING.
THIS LOW AND THE HIGH PRESSURE TO THE NORTH OF THE LAKES WILL
COMBINE TO RAPIDLY TIGHTEN THE SURFACE PRESSURE GRADIENT ACROSS THE
LAKE THIS MORNING...WITH NORTH-NORTHEAST WINDS INCREASING TO 25-30
KT. RECENT OBSERVATION PLATFORMS ALONG THE WEST SHORE OF THE LAKE
HAVE BEEN GUSTING 26-27 KTS BEHIND THE COLD FRONT AS FAR SOUTH AS
MILWAUKEE. THESE STRONGER WINDS WILL CONTINUE TO DEVELOP SOUTHWARD
DOWN THE REMAINDER OF THE LAKE THIS MORNING. FORECAST SOUNDINGS
INDICATE WINDS TO 30 KT WILL BE PREVALENT THROUGH THE DAY...WITH A
FEW GALE FORCE GUSTS TO 35 KT POSSIBLE. WINDS WILL REMAIN GUSTY INTO
THE EVENING HOURS ACROSS THE FAR SOUTHERN PORTION OF THE LAKE...BUT
WILL DIMINISH RAPIDLY FROM THE NORTH AS A WEAK RIDGE OF HIGH
PRESSURE SPREADS IN BEHIND THE QUICK MOVING LOW WHICH MOVE TO THE
CAROLINA COAST BY MONDAY MORNING.
THE WEAK RIDGE WILL MOVE QUICKLY SOUTHEAST OF THE LAKE MONDAY...
WITH WINDS BRIEFLY BECOMING SOUTHERLY AND INCREASING BACK AROUND 20
KT OR SO AHEAD OF ANOTHER LOW PRESSURE SYSTEM WHICH WILL DROP
SOUTHEAST ACROSS THE LAKE MONDAY NIGHT...WHILE FILLING. WEAK
GRADIENT CONDITIONS WILL THEN LINGER ACROSS THE LAKE TUESDAY AND
TUESDAY NIGHT AS THE TROUGH FILLS AND A WEAK RIDGE MOVES ACROSS THE
REGION. INDICATIONS ARE THAT ANOTHER LOW WILL DEVELOP ACROSS THE
PLAINS MID-WEEK...AND WILL APPROACH THE LAKE FROM THE WEST LATE
WEDNESDAY. THIS MAY RESULT IN A BRIEF PERIOD OF ENHANCED
EAST-SOUTHEAST WINDS LATE WEDNESDAY OR WEDNESDAY NIGHT...WITH A
PERIOD OF GUSTY NORTHERLY WINDS POSSIBLE THURSDAY AS THE LOW MOVES
EAST OF THE LAKE.
FOR THE IL/NORTHWEST INDIANA NEARSHORE AREA...SMALL CRAFT ADVISORY
IS IN EFFECT FROM 6 AM CST THIS MORNING AS WINDS/WAVES QUICKLY
INCREASE AND BUILD. ADVISORY HEADLINE WILL REMAIN IN EFFECT THROUGH
MID-MORNING MONDAY...AS WAVES SLOWLY SUBSIDE BELOW 4 FT.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-
LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 6 PM SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...6 PM SUNDAY TO 9 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
813 AM CST SUN JAN 25 2015
.SHORT TERM...
329 AM CST
THROUGH TONIGHT...
HAVE FURTHERED THE DIMINISHING SNOWFALL TREND IN THE FORECAST FOR
TODAY...MAINLY NORTH OF INTERSTATE 80. ACROSS THE ENTIRE AREA THIS
LOOKS TO BE A MAINLY LOW IMPACT...NUISANCE TYPE SNOW...WITH SOME
COMMUNITIES IN THE NORTH QUITE POSSIBLY NOT SEEING ANY
ACCUMULATION. HAVE CONTINUED A SPECIAL WEATHER STATEMENT FOR AREAS
ALONG AND SOUTH OF I-80.
SATELLITE IMAGERY THIS MORNING DEPICTS THE CLOSED UPPER CIRCULATION
ACROSS WESTERN IA WITH AN AREA OF COOLING CLOUD TOPS IN ADVANCE OF
THIS MOVING INTO NORTHWEST IL. THIS IS CORRELATING WITH MAINLY LIGHT
RAIN OR RAIN/SNOW MIX IN THE SMALL WINDOW OF DEEPER MOIST
ADVECTION AHEAD OF THE LOW. SIMPLE EXTRAPOLATION OF THE CURRENT
AREA OF PRECIP IN IOWA AND THE DEVELOPING DEFORMATION ON THE
BACKSIDE CLEARLY INDICATE THE SOUTHERN CWA IS MORE SUPPORTED FOR
PRECIPITATION THAN THE NORTH. AT THE SURFACE...TEMPERATURES ARE
AROUND OR JUST ABOVE FREEZING ACROSS MUCH OF THE FORECAST AREA. A
DEVELOPING COLD FRONT IS ADVANCING SOUTHWARD INTO NORTHERN IL WITH
DEW POINTS IN THE MID TO UPPER 20S NORTH OF THIS FEATURE...ANOTHER
HINDRANCE OF APPRECIABLE PRECIPITATION IN NORTHERN AREAS OF THE
FORECAST AREA.
SHORT RANGE GUIDANCE LIKE ITS LONG RANGE COUNTERPARTS THE PAST
SEVERAL DAYS SHOW A FAIR AMOUNT OF DISCREPANCY...NAMELY ON COVERAGE
OF PRECIP TODAY AND PRECIP TYPE IN THE SOUTHERN CWA THIS
MORNING...BUT THEY LEND SUPPORT TO THE OBSERVATIONAL TRENDS. AS
THE AREA OF RAIN ASSOCIATED WITH ELEVATED ISENTROPIC ASCENT MOVES
INTO THE SOUTHERN FORECAST AREA...PROFILES SUPPORT A PERIOD OF
RAIN OR MIX INITIALLY...AND SOME LOCATIONS MIGHT HAVE AIR
TEMPERATURES RIGHT AT FREEZING. WOULD EXPECT ANY FREEZING RAIN
THREAT TO BE SHORT LIVED AS PROFILES TREND TOWARD SNOW. MESOSCALE
CONVERGENCE AND BAROCLINIC FORCING FOR INDUCED LIFT WOULD BECOME
MORE FAVORED JUST TO THE NORTHEAST OF THE CLOSED 850MB
CIRCULATION AS IT PIVOTS MORE EASTWARD. THAT IS FAVORED ACROSS
THE SOUTHERN TIER OR TWO OF COUNTIES LATER THIS MORNING INTO
EARLY AFTERNOON. PROFILES ARE MILD FOR IDEAL SNOW GROWTH...AND
MAYBE EVEN FOR SNOW AT ALL DOWN TOWARD GIBSON CITY FOR MUCH OF THE
MORNING. HAVE SNOW TOTALS AROUND ONE TO TWO INCHES FROM PERU TO
RENSSELAER AND SOUTHWARD FOR TODAY...WITH SNOW DEPARTING NEAR OR
SOON AFTER SUNDOWN.
AS FOR AREAS NORTH OF INTERSTATE 80...SHOULD SEE A GRADUAL INCREASE
IN LIGHT SNOW AREAWIDE BY MID-MORNING. DRY CORRIDOR NEAR 850MB
SEEN ON EARLY MORNING AMDAR SOUNDINGS OVER CHICAGO SHOULD LIMIT
INTENSITY OF ANY SNOW IN THE NORTHERN FORECAST AREA...AS WILL JUST
LESS FORCING. AREAS OF NORTHEAST ILLINOIS STILL LOOK TO HAVE
ONSHORE FLOW BEHIND THE COLD FRONT...BUT FORECAST INVERSION
HEIGHTS AS WELL AS ADAPTED ONES FROM THE 00Z GRB RAOB LAST
EVE...INDICATE VERY MARGINAL DEPTH OF CONVECTIVE CLOUDS. THUS NOT
EXPECTING MUCH IF ANY ENHANCEMENT TO ALREADY MINIMAL SYNOPTIC
FORCING OVER NORTHEAST IL. COULD SEE SOME DISORGANIZED LIGHT SNOW
OR FLURRIES LATE THIS AFTERNOON INTO THIS EVENING AS PROFILES OF
THE LAKE INDUCED STRATOCU COOL INTO THE ICE INITIATION LAYER...BUT
THIS SHOULD NOT BE A BIG DEAL.
AREAWIDE THE NORTHEAST WINDS WILL INCREASE TO 30 MPH AND MAYBE EVEN
A LITTLE HIGHER JUST OF THE LAKE. WITH MINIMAL SNOW NORTH NOT
EXPECTING ANY BLOWING SNOW ISSUES...AND SOUTH THE LOW SNOW-TO-
LIQUID RATIOS SHOULD SUPPRESS MUCH FOR BLOWING ISSUES...THOUGH
COULD LEAD TO MORE REDUCED VISIBILITY DURING THE TIME OF FALLING
SNOW THIS AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
MONDAY THROUGH SATURDAY...
THE DISTURBED FLOW PATTERN WILL TURN MORE NORTHWESTERLY MONDAY AND
TUESDAY AS A MAJOR SYSTEM IS EXPECTED TO DEVELOP OFF THE NORTHEAST
COAST. GIVEN THIS POSSIBLY LEADING TO A SLOWER PATTERN...AS WELL
AS THE TREND OF TODAYS SYSTEM...IT IS QUITE CONCEIVABLE THAT THE
NEXT DISTURBANCE FOR MONDAY AFTERNOON AND NIGHT TRENDS WEST AS
WELL...WHICH THE EC HAS HAD IN ITS SOLUTION FOR THREE CONSECUTIVE
RUNS. THIS SYSTEM THOUGH IS NOT AS STRONG AS TODAYS AS IT IS MORE
OF A SHEARED AREA OF VORTICITY ALONG THE LINGERING BAROCLINIC
ZONE. FORCING FOR PRECIP LOOKS PRETTY LIGHT ONCE AGAIN MONDAY
AFTERNOON AND NIGHT BUT ENOUGH TO GO A LITTLE HIGHER ON POPS FOR
NORTHERN PARTS OF THE FORECAST AREA. RIGHT NOW GUIDANCE IS IN
DECENT AGREEMENT WITH SATURATING DEEP ENOUGH FOR PRECIP TYPE TO BE
LIGHT SNOW IF IT CAN OCCUR...BUT NEED TO KEEP AN EYE OUT FOR SOME
FREEZING DRIZZLE POTENTIAL IN THESE LIGHT ASCENT SITUATIONS.
A SLOW MODERATION LOOKS TO OCCUR TUESDAY INTO WEDNESDAY AND THIS
COULD BE VERY MINIMAL DEPENDING ON CLOUD COVER WHICH REMAINS A BIG
QUESTION MARK. HAVE LEANED MORE CLOUDY TUESDAY BUT STILL THINK
WITH A WESTERLY PUSH WEDNESDAY WOULD HAVE SUN POTENTIAL. LONG
RANGE GUIDANCE INDICATES A PACIFIC SYSTEM TO BE THE NEXT ONE TO
POSSIBLY BRING PRECIPITATION TO THE AREA WEDNESDAY NIGHT INTO
THURSDAY. CONTINUE POPS DURING THIS TIME FRAME AND AT THIS POINT
PROFILES ARE NEAR THE BORDER FOR RAIN OR SNOW...SO DID NOT GET TOO
FANCY WITH THE FORECAST PRECIPITATION TYPE. BEHIND THIS SYSTEM IT
SEEMS FAVORED FOR TEMPERATURES TO COOL SOME DURING THE LATTER
HALF OF THE WEEK...TO SLIGHTLY BELOW NORMAL VALUES. OBVIOUSLY ANY
FRESH SNOW COVER WOULD HELP LEAN THAT MORE TOWARD BELOW NORMAL.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* LIGHT SNOW THROUGH THIS AFTERNOON...MIXING WITH LIGHT RAIN/SLEET
THIS MORNING WITH IFR VIS POSSIBLE.
* IFR CIGS LIFTING TO MVFR THIS AFTERNOON...THEN SCATTERING OUT
TONIGHT.
* STRONG/GUSTY NORTHEAST WINDS THRU MID EVENING. CMS
//DISCUSSION...UPDATED 14Z...
LOW PRESSURE OVER NORTHEAST MISSOURI WILL MOVE ACROSS THE OHIO
VALLEY TONIGHT. NORTHEAST WINDS WILL REMAIN STRONG AND GUSTY THRU
THIS EVENING WITH GUSTS IN THE MID/UPPER 20KT RANGE. HEAVIEST
PRECIP SHOULD REMAIN ALONG AND SOUTH OF I-80 WITH LIGHTER AMOUNTS
NORTH. MANY AREAS REPORTING LIGHT SNOW BUT STILL SOME MIXED RAIN
AT MDW AND GYY...WHICH SHOULD TRANSITION TO SNOW BY LATE MORNING.
CMS
PREVIOUS 12Z DISCUSSION...
WEAK COLD FRONTAL BOUNDARY HAS SAGGED INTO NORTHEAST ILLINOIS
EARLY THIS MORNING...WITH IFR/LIFR CIGS NOTED IN THE VICINITY OF
THE FRONTAL BOUNDARY. EXPECT THE LIFR CIGS TO BE SOMEWHAT SHORT-
LIVED HOWEVER...AS WINDS RAMP UP FROM THE NORTHEAST.
RADAR CLEARLY SHOWS CIRCULATION WITH ALBERTA CLIPPER DROPPING
SOUTHEAST ACROSS IA...WITH EXPANSION OF WEAK RETURNS OVER NORTHERN
ILLINOIS AND A FEW REPORTS OF LIGHT SNOW BEGINNING TO REACH THE
GROUND. HIGH-RES HRRR HAS BEEN FAIRLY CONSISTENT IN BRINING NORTH
EDGE OF MORE ORGANIZED SNOW BAND ACROSS THE TERMINALS THIS MORNING
INTO MIDDAY/EARLY AFTERNOON...AND IS EXPECTED TO PRODUCE A PERIOD
OF LIGHT ACCUMULATING SNOW WITH OCCASIONAL IFR VSBYS. SNOW SHOULD
TAPER OFF TO LIGHT SNOW SHOWERS/FLURRIES THIS AFTERNOON WITH CIGS
RISING TO MVFR.
AS INDICATED ABOVE...STRONG/GUSTY NORTHEAST WINDS ARE ALREADY
RAMPING UP EARLY THIS MORNING WITH GUSTS 20-30 KT ALREAD ACROSS
FAR NORTHERN IL. 040-060 DEG WINDS NEAR 20 KT WITH GUSTS NEAR 30
KT ARE EXPECTED TO CONTIUNE INTO THE AFTERNOON BEFORE SLOW DECLINE
IN WIND SPEEDS AND A GRADUAL BACKING TO THE NORTH OCCURS. WINDS
WILL DIMINISH MORE QUICKLY TONIGHT...AS A WEAK HIGH PRESSURE RIDGE
BUILDS IN FROM THE NORTHWEST. THIS SHOULD ALLOW LOWER CLOUDS TO
SCATTER OUT OVERNIGHT.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH FOR LIGHT SNOW...MEDIUM FOR INTENSITY AND MIXED PRECIP.
* HIGH FOR CIGS THRU THIS AFTERNOON...THEN MEDIUM FOR THE REST OF
THE PERIOD.
* HIGH FOR WIND SPEEDS/GUSTS/DIRECTIONS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...CHANCE LIGHT SNOW/MVFR.
TUESDAY...MVFR CIGS POSSIBLE.
WEDNESDAY...MAINLY VFR DURING THE DAY THEN CHANCE OF -RASN AND
MVFR/IFR AT NIGHT.
THURSDAY...CHANCE OF SNOW. MVFR/IFR POSSIBLE.
FRIDAY...CHANCE OF MVFR CIGS.
SATURDAY...CHANCE OF LIGHT SNOW/MVFR.
RATZER
&&
.MARINE...
137 AM CST
MAIN MARINE FORECAST FOCUS CONTINUES TO BE A PERIOD OF STRONG
NORTHEAST WINDS ACROSS THE SOUTHERN 2/3 OR SO OF LAKE MICHIGAN
THROUGH THIS EVENING.
A COLD FRONT HAS PUSHED SOUTH ACROSS MUCH OF LAKE MICHIGAN SINCE
SATURDAY MORNING...WITH COLD HIGH PRESSURE SPREADING ACROSS
MANITOBA...WESTERN ONTARIO AND THE NORTHERN LAKES. EARLY THIS
MORNING AN AREA OF LOW PRESSURE WAS OVER IOWA...AND THIS LOW WILL
MOVE QUICKLY SOUTHEAST TO THE LOWER OHIO VALLEY BY THIS EVENING.
THIS LOW AND THE HIGH PRESSURE TO THE NORTH OF THE LAKES WILL
COMBINE TO RAPIDLY TIGHTEN THE SURFACE PRESSURE GRADIENT ACROSS THE
LAKE THIS MORNING...WITH NORTH-NORTHEAST WINDS INCREASING TO 25-30
KT. RECENT OBSERVATION PLATFORMS ALONG THE WEST SHORE OF THE LAKE
HAVE BEEN GUSTING 26-27 KTS BEHIND THE COLD FRONT AS FAR SOUTH AS
MILWAUKEE. THESE STRONGER WINDS WILL CONTINUE TO DEVELOP SOUTHWARD
DOWN THE REMAINDER OF THE LAKE THIS MORNING. FORECAST SOUNDINGS
INDICATE WINDS TO 30 KT WILL BE PREVALENT THROUGH THE DAY...WITH A
FEW GALE FORCE GUSTS TO 35 KT POSSIBLE. WINDS WILL REMAIN GUSTY INTO
THE EVENING HOURS ACROSS THE FAR SOUTHERN PORTION OF THE LAKE...BUT
WILL DIMINISH RAPIDLY FROM THE NORTH AS A WEAK RIDGE OF HIGH
PRESSURE SPREADS IN BEHIND THE QUICK MOVING LOW WHICH MOVE TO THE
CAROLINA COAST BY MONDAY MORNING.
THE WEAK RIDGE WILL MOVE QUICKLY SOUTHEAST OF THE LAKE MONDAY...
WITH WINDS BRIEFLY BECOMING SOUTHERLY AND INCREASING BACK AROUND 20
KT OR SO AHEAD OF ANOTHER LOW PRESSURE SYSTEM WHICH WILL DROP
SOUTHEAST ACROSS THE LAKE MONDAY NIGHT...WHILE FILLING. WEAK
GRADIENT CONDITIONS WILL THEN LINGER ACROSS THE LAKE TUESDAY AND
TUESDAY NIGHT AS THE TROUGH FILLS AND A WEAK RIDGE MOVES ACROSS THE
REGION. INDICATIONS ARE THAT ANOTHER LOW WILL DEVELOP ACROSS THE
PLAINS MID-WEEK...AND WILL APPROACH THE LAKE FROM THE WEST LATE
WEDNESDAY. THIS MAY RESULT IN A BRIEF PERIOD OF ENHANCED
EAST-SOUTHEAST WINDS LATE WEDNESDAY OR WEDNESDAY NIGHT...WITH A
PERIOD OF GUSTY NORTHERLY WINDS POSSIBLE THURSDAY AS THE LOW MOVES
EAST OF THE LAKE.
FOR THE IL/NORTHWEST INDIANA NEARSHORE AREA...SMALL CRAFT ADVISORY
IS IN EFFECT FROM 6 AM CST THIS MORNING AS WINDS/WAVES QUICKLY
INCREASE AND BUILD. ADVISORY HEADLINE WILL REMAIN IN EFFECT THROUGH
MID-MORNING MONDAY...AS WAVES SLOWLY SUBSIDE BELOW 4 FT.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 9 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
549 AM CST SUN JAN 25 2015
.SHORT TERM...
329 AM CST
THROUGH TONIGHT...
HAVE FURTHERED THE DIMINISHING SNOWFALL TREND IN THE FORECAST FOR
TODAY...MAINLY NORTH OF INTERSTATE 80. ACROSS THE ENTIRE AREA THIS
LOOKS TO BE A MAINLY LOW IMPACT...NUISANCE TYPE SNOW...WITH SOME
COMMUNITIES IN THE NORTH QUITE POSSIBLY NOT SEEING ANY
ACCUMULATION. HAVE CONTINUED A SPECIAL WEATHER STATEMENT FOR AREAS
ALONG AND SOUTH OF I-80.
SATELLITE IMAGERY THIS MORNING DEPICTS THE CLOSED UPPER CIRCULATION
ACROSS WESTERN IA WITH AN AREA OF COOLING CLOUD TOPS IN ADVANCE OF
THIS MOVING INTO NORTHWEST IL. THIS IS CORRELATING WITH MAINLY LIGHT
RAIN OR RAIN/SNOW MIX IN THE SMALL WINDOW OF DEEPER MOIST
ADVECTION AHEAD OF THE LOW. SIMPLE EXTRAPOLATION OF THE CURRENT
AREA OF PRECIP IN IOWA AND THE DEVELOPING DEFORMATION ON THE
BACKSIDE CLEARLY INDICATE THE SOUTHERN CWA IS MORE SUPPORTED FOR
PRECIPITATION THAN THE NORTH. AT THE SURFACE...TEMPERATURES ARE
AROUND OR JUST ABOVE FREEZING ACROSS MUCH OF THE FORECAST AREA. A
DEVELOPING COLD FRONT IS ADVANCING SOUTHWARD INTO NORTHERN IL WITH
DEW POINTS IN THE MID TO UPPER 20S NORTH OF THIS FEATURE...ANOTHER
HINDRANCE OF APPRECIABLE PRECIPITATION IN NORTHERN AREAS OF THE
FORECAST AREA.
SHORT RANGE GUIDANCE LIKE ITS LONG RANGE COUNTERPARTS THE PAST
SEVERAL DAYS SHOW A FAIR AMOUNT OF DISCREPANCY...NAMELY ON COVERAGE
OF PRECIP TODAY AND PRECIP TYPE IN THE SOUTHERN CWA THIS
MORNING...BUT THEY LEND SUPPORT TO THE OBSERVATIONAL TRENDS. AS
THE AREA OF RAIN ASSOCIATED WITH ELEVATED ISENTROPIC ASCENT MOVES
INTO THE SOUTHERN FORECAST AREA...PROFILES SUPPORT A PERIOD OF
RAIN OR MIX INITIALLY...AND SOME LOCATIONS MIGHT HAVE AIR
TEMPERATURES RIGHT AT FREEZING. WOULD EXPECT ANY FREEZING RAIN
THREAT TO BE SHORT LIVED AS PROFILES TREND TOWARD SNOW. MESOSCALE
CONVERGENCE AND BAROCLINIC FORCING FOR INDUCED LIFT WOULD BECOME
MORE FAVORED JUST TO THE NORTHEAST OF THE CLOSED 850MB
CIRCULATION AS IT PIVOTS MORE EASTWARD. THAT IS FAVORED ACROSS
THE SOUTHERN TIER OR TWO OF COUNTIES LATER THIS MORNING INTO
EARLY AFTERNOON. PROFILES ARE MILD FOR IDEAL SNOW GROWTH...AND
MAYBE EVEN FOR SNOW AT ALL DOWN TOWARD GIBSON CITY FOR MUCH OF THE
MORNING. HAVE SNOW TOTALS AROUND ONE TO TWO INCHES FROM PERU TO
RENSSELAER AND SOUTHWARD FOR TODAY...WITH SNOW DEPARTING NEAR OR
SOON AFTER SUNDOWN.
AS FOR AREAS NORTH OF INTERSTATE 80...SHOULD SEE A GRADUAL INCREASE
IN LIGHT SNOW AREAWIDE BY MID-MORNING. DRY CORRIDOR NEAR 850MB
SEEN ON EARLY MORNING AMDAR SOUNDINGS OVER CHICAGO SHOULD LIMIT
INTENSITY OF ANY SNOW IN THE NORTHERN FORECAST AREA...AS WILL JUST
LESS FORCING. AREAS OF NORTHEAST ILLINOIS STILL LOOK TO HAVE
ONSHORE FLOW BEHIND THE COLD FRONT...BUT FORECAST INVERSION
HEIGHTS AS WELL AS ADAPTED ONES FROM THE 00Z GRB RAOB LAST
EVE...INDICATE VERY MARGINAL DEPTH OF CONVECTIVE CLOUDS. THUS NOT
EXPECTING MUCH IF ANY ENHANCEMENT TO ALREADY MINIMAL SYNOPTIC
FORCING OVER NORTHEAST IL. COULD SEE SOME DISORGANIZED LIGHT SNOW
OR FLURRIES LATE THIS AFTERNOON INTO THIS EVENING AS PROFILES OF
THE LAKE INDUCED STRATOCU COOL INTO THE ICE INITIATION LAYER...BUT
THIS SHOULD NOT BE A BIG DEAL.
AREAWIDE THE NORTHEAST WINDS WILL INCREASE TO 30 MPH AND MAYBE EVEN
A LITTLE HIGHER JUST OF THE LAKE. WITH MINIMAL SNOW NORTH NOT
EXPECTING ANY BLOWING SNOW ISSUES...AND SOUTH THE LOW SNOW-TO-
LIQUID RATIOS SHOULD SUPPRESS MUCH FOR BLOWING ISSUES...THOUGH
COULD LEAD TO MORE REDUCED VISIBILITY DURING THE TIME OF FALLING
SNOW THIS AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
MONDAY THROUGH SATURDAY...
THE DISTURBED FLOW PATTERN WILL TURN MORE NORTHWESTERLY MONDAY AND
TUESDAY AS A MAJOR SYSTEM IS EXPECTED TO DEVELOP OFF THE NORTHEAST
COAST. GIVEN THIS POSSIBLY LEADING TO A SLOWER PATTERN...AS WELL
AS THE TREND OF TODAYS SYSTEM...IT IS QUITE CONCEIVABLE THAT THE
NEXT DISTURBANCE FOR MONDAY AFTERNOON AND NIGHT TRENDS WEST AS
WELL...WHICH THE EC HAS HAD IN ITS SOLUTION FOR THREE CONSECUTIVE
RUNS. THIS SYSTEM THOUGH IS NOT AS STRONG AS TODAYS AS IT IS MORE
OF A SHEARED AREA OF VORTICITY ALONG THE LINGERING BAROCLINIC
ZONE. FORCING FOR PRECIP LOOKS PRETTY LIGHT ONCE AGAIN MONDAY
AFTERNOON AND NIGHT BUT ENOUGH TO GO A LITTLE HIGHER ON POPS FOR
NORTHERN PARTS OF THE FORECAST AREA. RIGHT NOW GUIDANCE IS IN
DECENT AGREEMENT WITH SATURATING DEEP ENOUGH FOR PRECIP TYPE TO BE
LIGHT SNOW IF IT CAN OCCUR...BUT NEED TO KEEP AN EYE OUT FOR SOME
FREEZING DRIZZLE POTENTIAL IN THESE LIGHT ASCENT SITUATIONS.
A SLOW MODERATION LOOKS TO OCCUR TUESDAY INTO WEDNESDAY AND THIS
COULD BE VERY MINIMAL DEPENDING ON CLOUD COVER WHICH REMAINS A BIG
QUESTION MARK. HAVE LEANED MORE CLOUDY TUESDAY BUT STILL THINK
WITH A WESTERLY PUSH WEDNESDAY WOULD HAVE SUN POTENTIAL. LONG
RANGE GUIDANCE INDICATES A PACIFIC SYSTEM TO BE THE NEXT ONE TO
POSSIBLY BRING PRECIPITATION TO THE AREA WEDNESDAY NIGHT INTO
THURSDAY. CONTINUE POPS DURING THIS TIME FRAME AND AT THIS POINT
PROFILES ARE NEAR THE BORDER FOR RAIN OR SNOW...SO DID NOT GET TOO
FANCY WITH THE FORECAST PRECIPITATION TYPE. BEHIND THIS SYSTEM IT
SEEMS FAVORED FOR TEMPERATURES TO COOL SOME DURING THE LATTER
HALF OF THE WEEK...TO SLIGHTLY BELOW NORMAL VALUES. OBVIOUSLY ANY
FRESH SNOW COVER WOULD HELP LEAN THAT MORE TOWARD BELOW NORMAL.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* IFR CIGS EARLY WITH LIGHT SNOW DEVELOPING THIS MORNING. CIGS MAY
ACTUALLY COME UP A BIT WITH THE SNOW...THOUGH VSBYS MVFR/OCNL
IFR ARE PROBABLE WITH SOME LIGHT ACCUMULATION. SNOW EXPECTED TO
TAPER OFF TO LIGHT SHSN/FLURRIES BY EARLY AFTERNOON.
* MVFR CIGS EXPECTED THIS AFTERNOON AND THIS EVENING.
* STRONG GUSTY NORTHEAST WINDS AROUND 30 KT AT TIMES. WINDS SLOWLY
DIMINISH THROUGH THIS EVENING.
RATZER
//DISCUSSION...UPDATED 12Z...
WEAK COLD FRONTAL BOUNDARY HAS SAGGED INTO NORTHEAST ILLINOIS
EARLY THIS MORNING...WITH IFR/LIFR CIGS NOTED IN THE VICINITY OF
THE FRONTAL BOUNDARY. EXPECT THE LIFR CIGS TO BE SOMEWHAT SHORT-
LIVED HOWEVER...AS WINDS RAMP UP FROM THE NORTHEAST.
RADAR CLEARLY SHOWS CIRCULATION WITH ALBERTA CLIPPER DROPPING
SOUTHEAST ACROSS IA...WITH EXPANSION OF WEAK RETURNS OVER NORTHERN
ILLINOIS AND A FEW REPORTS OF LIGHT SNOW BEGINNING TO REACH THE
GROUND. HIGH-RES HRRR HAS BEEN FAIRLY CONSISTENT IN BRINING NORTH
EDGE OF MORE ORGANIZED SNOW BAND ACROSS THE TERMINALS THIS MORNING
INTO MIDDAY/EARLY AFTERNOON...AND IS EXPECTED TO PRODUCE A PERIOD
OF LIGHT ACCUMULATING SNOW WITH OCCASIONAL IFR VSBYS. SNOW SHOULD
TAPER OFF TO LIGHT SNOW SHOWERS/FLURRIES THIS AFTERNOON WITH CIGS
RISING TO MVFR.
AS INDICATED ABOVE...STRONG/GUSTY NORTHEAST WINDS ARE ALREADY
RAMPING UP EARLY THIS MORNING WITH GUSTS 20-30 KT ALREAD ACROSS
FAR NORTHERN IL. 040-060 DEG WINDS NEAR 20 KT WITH GUSTS NEAR 30
KT ARE EXPECTED TO CONTIUNE INTO THE AFTERNOON BEFORE SLOW DECLINE
IN WIND SPEEDS AND A GRADUAL BACKING TO THE NORTH OCCURS. WINDS
WILL DIMINISH MORE QUICKLY TONIGHT...AS A WEAK HIGH PRESSURE RIDGE
BUILDS IN FROM THE NORTHWEST. THIS SHOULD ALLOW LOWER CLOUDS TO
SCATTER OUT OVERNIGHT.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH IN WIND TRENDS.
* MEDIUM-HIGH IN SNOW TIMING...MEDIUM IN DETAILS OF CIG/VSBY
THROUGH MID-DAY.
* MEDIUM-LOW IN TIMING OF SCATTERING MVFR CIGS TONIGHT.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...CHANCE LIGHT SNOW/MVFR.
TUESDAY...MVFR CIGS POSSIBLE.
WEDNESDAY...MAINLY VFR DURING THE DAY THEN CHANCE OF -RASN AND
MVFR/IFR AT NIGHT.
THURSDAY...CHANCE OF SNOW. MVFR/IFR POSSIBLE.
FRIDAY...CHANCE OF MVFR CIGS.
SATURDAY...CHANCE OF LIGHT SNOW/MVFR.
RATZER
&&
.MARINE...
137 AM CST
MAIN MARINE FORECAST FOCUS CONTINUES TO BE A PERIOD OF STRONG
NORTHEAST WINDS ACROSS THE SOUTHERN 2/3 OR SO OF LAKE MICHIGAN
THROUGH THIS EVENING.
A COLD FRONT HAS PUSHED SOUTH ACROSS MUCH OF LAKE MICHIGAN SINCE
SATURDAY MORNING...WITH COLD HIGH PRESSURE SPREADING ACROSS
MANITOBA...WESTERN ONTARIO AND THE NORTHERN LAKES. EARLY THIS
MORNING AN AREA OF LOW PRESSURE WAS OVER IOWA...AND THIS LOW WILL
MOVE QUICKLY SOUTHEAST TO THE LOWER OHIO VALLEY BY THIS EVENING.
THIS LOW AND THE HIGH PRESSURE TO THE NORTH OF THE LAKES WILL
COMBINE TO RAPIDLY TIGHTEN THE SURFACE PRESSURE GRADIENT ACROSS THE
LAKE THIS MORNING...WITH NORTH-NORTHEAST WINDS INCREASING TO 25-30
KT. RECENT OBSERVATION PLATFORMS ALONG THE WEST SHORE OF THE LAKE
HAVE BEEN GUSTING 26-27 KTS BEHIND THE COLD FRONT AS FAR SOUTH AS
MILWAUKEE. THESE STRONGER WINDS WILL CONTINUE TO DEVELOP SOUTHWARD
DOWN THE REMAINDER OF THE LAKE THIS MORNING. FORECAST SOUNDINGS
INDICATE WINDS TO 30 KT WILL BE PREVALENT THROUGH THE DAY...WITH A
FEW GALE FORCE GUSTS TO 35 KT POSSIBLE. WINDS WILL REMAIN GUSTY INTO
THE EVENING HOURS ACROSS THE FAR SOUTHERN PORTION OF THE LAKE...BUT
WILL DIMINISH RAPIDLY FROM THE NORTH AS A WEAK RIDGE OF HIGH
PRESSURE SPREADS IN BEHIND THE QUICK MOVING LOW WHICH MOVE TO THE
CAROLINA COAST BY MONDAY MORNING.
THE WEAK RIDGE WILL MOVE QUICKLY SOUTHEAST OF THE LAKE MONDAY...
WITH WINDS BRIEFLY BECOMING SOUTHERLY AND INCREASING BACK AROUND 20
KT OR SO AHEAD OF ANOTHER LOW PRESSURE SYSTEM WHICH WILL DROP
SOUTHEAST ACROSS THE LAKE MONDAY NIGHT...WHILE FILLING. WEAK
GRADIENT CONDITIONS WILL THEN LINGER ACROSS THE LAKE TUESDAY AND
TUESDAY NIGHT AS THE TROUGH FILLS AND A WEAK RIDGE MOVES ACROSS THE
REGION. INDICATIONS ARE THAT ANOTHER LOW WILL DEVELOP ACROSS THE
PLAINS MID-WEEK...AND WILL APPROACH THE LAKE FROM THE WEST LATE
WEDNESDAY. THIS MAY RESULT IN A BRIEF PERIOD OF ENHANCED
EAST-SOUTHEAST WINDS LATE WEDNESDAY OR WEDNESDAY NIGHT...WITH A
PERIOD OF GUSTY NORTHERLY WINDS POSSIBLE THURSDAY AS THE LOW MOVES
EAST OF THE LAKE.
FOR THE IL/NORTHWEST INDIANA NEARSHORE AREA...SMALL CRAFT ADVISORY
IS IN EFFECT FROM 6 AM CST THIS MORNING AS WINDS/WAVES QUICKLY
INCREASE AND BUILD. ADVISORY HEADLINE WILL REMAIN IN EFFECT THROUGH
MID-MORNING MONDAY...AS WAVES SLOWLY SUBSIDE BELOW 4 FT.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 AM MONDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 9 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1142 PM CST SAT JAN 24 2015
.UPDATE...
900 PM CST
EVENING UPDATE...
HAVE UPDATED GRIDS TO REFLECT MUCH LOWER SNOWFALL AMOUNTS ON SUNDAY
TO THE NORTH OF INTERSTATE 80 AND ALSO SLOWED ARRIVAL OF
PRECIPITATION MAINLY TO EARLY TO MID SUNDAY MORNING. RADAR...SURFACE
ANALYSIS AND SATELLITE TRENDS SUPPORT THE NEW 00Z GUIDANCE AND
LATEST HIGHER RESOLUTION GUIDANCE ROLLING IN DIGGING THE 500 MB WAVE
FARTHER SOUTHWEST AND ASSOCIATED SURFACE LOW FARTHER SOUTHWEST AND
THEN SOUTH OF THE CWA. NOW LOOKING AT GENERALLY AROUND A FEW TENTHS
TO UP TO AN INCH NORTH OF INTERSTATE 88...ONE TO TWO INCHES BETWEEN
I-88 AND I-80 AND ONE TO THREE INCHES SOUTH OF INTERSTATE 80. IF THE
FARTHER SOUTH TREND BECOMES MORE AGGRESSIVE AS THE SYSTEM APPROACHES
SUNDAY...THEN EVEN THESE AMOUNTS COULD END UP BEING TOO HIGH.
NAM/WRF AND OTHER HIGHER-RES GUIDANCE CONTINUES TO HINT AT LAKE
ENHANCEMENT DURING THE DAY SUNDAY INTO THE AFTERNOON INTO PARTS OF
NORTHEAST IL AND NW IN...BUT UNLESS FRICTIONAL CONVERGENCE CAN
ENHANCE RATES A BIT...THE THERMODYNAMICS AND INVERSION HEIGHTS ARE
VERY MARGINAL TO ACTUALLY ADD MUCH TO SNOW TOTALS.
REGARDING THE MIXED PRECIPITATION IN THE SOUTHERN CWA...THE
SOUTHWARD TREND AND DELAYED TIMING OF THE SYSTEM SHOULD ALLOW FOR
COLDER AIR TO BLEED SOUTHWARD AND SUPPRESS THE MIXING ZONE SOUTHWARD
FROM THE PREVIOUS FORECAST. ANY WINTRY MIX/RAIN SNOW MIX IN THE FAR
SOUTHERN CWA WILL LIKELY TRANSITION TO SNOW BY MID DAY/EARLY
AFTERNOON.
UPDATED ZONES WILL BE SENT SHORTLY.
RC/KREIN
&&
.SHORT TERM...
250 PM CST
THROUGH SUNDAY...
MAIN FORECAST CONCERN WILL BE PASSAGE OF A CLIPPER SYSTEM ACROSS THE
MIDWEST BRINGING ACCUMULATING SNOWFALL AND FOR SOME AREAS A WINTRY
MIX OF PRECIPITATION. CLOUD COVER WILL CONTINUE TO INCREASE THE
REMAINDER OF THE TODAY AS THE LOW DIVES ACROSS THE DAKOTAS INTO
MINNESOTA. MODELS ARE IN DECENT AGREEMENT TRACKING THE SURFACE LOW
ACROSS FAR NE MO LATE TONIGHT INTO DOWNSTATE IL BY SUNDAY AFTERNOON.
1000MB-700MB LAYER MAX WETBULBS ARE UP TO 2C SOUTH OF THE I-80
CORRIDOR THROUGH LATE MORNING/EARLY AFTERNOON SUNDAY...THEN START TO
FALL QUICKLY FROM THE NORTH THROUGH THE AFTERNOON HOURS. WITH THAT
IN MIND...THINK THAT PRECIP WILL BEGIN AS PRIMARILY SNOW NORTH OF
THE I-80 CORRIDOR WITH RAIN/SLEET TO THE SOUTH...EVENTUALLY CHANGING
OVER TO ALL SNOW. MODELS IN GENERAL HAVE THE AXIS OF HIGHEST QPF
SOUTH OF I-80...BUT WITH WARMER TEMPERATURES...IT APPEARS THE
HIGHEST SNOWFALL MAY OCCUR A LITTLE FARTHER NORTH. DID BUMP UP SNOW
TOTALS ACROSS PORTIONS OF THE CHICAGO METRO WHERE MODELS CONTINUE TO
ADVERTISE AN INCREASE IN THE LOW LEVEL LAPSE RATES AS WINDS TURN NE
OFF LAKE MICHIGAN WITH LAKE ENHANCEMENT APPEARING AT LEAST POSSIBLE.
NAM AND REGIONAL GEM GUIDANCE BOTH SHOW A SLIGHT MAX IN THE QPF
VALUES OVER THE AREA AND HAVE BEEN CONSISTENTLY ADVERTISING A BUMP IN
THE LOW LEVEL OMEGA STARTING LATE MORNING INTO THE AFTERNOON.
FORECAST SNOW TOTALS FOR THIS EVENT WILL BE 1-3 INCHES WEST OF A
WAUKEGAN TO STREATOR LINE...AND 2-4 INCHES EAST. WILL HAVE TO
MONITOR THE MESOSCALE BANDING THREAT FOR SOME LOCALLY HIGHER
AMOUNTS. NAM GUIDANCE IN PARTICULAR WAS HINTING AT AN AREA OF LOW
LEVEL FGEN DEVELOPING FOR EAST CENTRAL IL AND NORTHWEST
INDIANA...BUT LAPSE RATES UPSTAIRS ARENT OVERLY IMPRESSIVE IN THE
LATEST MODELS RUNS. ALSO SURFACE LOW SLOWLY FILLING AS IT MOVES
TOWARDS THE OHIO VALLEY WILL ALSO BE A LIMITING FACTOR. WILL ISSUE
AN UPDATED SPS THIS AFTERNOON FOR THE SNOWFALL. AS MENTIONED...STILL
CANNOT RULE OUT SOME LOCALLY HIGHER AMOUNTS THAT MIGHT REQUIRE AN
ADVISORY HOWEVER DONT HAVE MUCH CONFIDENCE WHERE OR EVEN IF THIS
WOULD OCCUR.
WINDS WILL START TO RAMP UP FROM EARLY MORNING ON OUT OF THE
NORTHEAST AS A TIGHT GRADIENT SWEEPS ACROSS THE REGION ON THE BACK
SIDE OF THE LOW. NORTHEAST WINDS ARE EXPECTED TO GUST 30-35 MPH AT
TIMES ACROSS THE AREA. THESE MODERATELY STRONG NORTHEAST WINDS OVER
LAKE MICHIGAN WILL DRIVE 8-11 FOOT WAVES INTO THE NEARSHORE WATERS
AND SOME OF THESE WAVES MAY RESULT IN SOME MINOR LAKE SHORE FLOODING
TO EXPOSED AREAS. IN ADDITION...BLOWING SNOW MAY BECOME A PROBLEM
ESPECIALLY IN OPEN AREAS. WETTER THAN AVERAGE SNOW...PARTICULARLY
SOUTH OF I-80 MAY HELP LIMIT THE BLOWING SNOW SOME.
DEUBELBEISS
&&
.LONG TERM...
SUNDAY NIGHT THROUGH SATURDAY...
250 PM...FORECAST CONCERNS INCLUDE A CHANCE OF LIGHT SNOW MONDAY
AFTERNOON INTO MONDAY NIGHT AND THEN THE POTENTIAL FOR A WINTRY
MIX WEDNESDAY NIGHT.
LIGHT SNOW WILL BE ENDING ACROSS THE SOUTHEAST CWA SUNDAY EVENING
AS NORTHEAST WINDS STEADILY DIMINISH SUNDAY EVENING. LAKE EFFECT
CLOUDS AND PERHAPS A FEW FLURRIES ARE POSSIBLE SUNDAY EVENING. LOWS
BY MONDAY MORNING WILL DIP INTO THE TEENS MOST LOCATIONS BUT AS A
WEAK RIDGE PASSES ACROSS THE AREA AND WINDS BECOME LIGHT OR CALM...
LOWS COULD BE SEVERAL DEGREES COLDER DEPENDING ON CLOUD COVER.
ANOTHER WEAK CLIPPER SYSTEM MOVES SOUTHEAST ACROSS THE WESTERN
LAKES MONDAY AFTERNOON INTO MONDAY NIGHT AS IT SLOWLY BEGINS TO
WEAKEN. MODELS VARY SOME ON TIMING AND PRECIP ARRIVAL. A CONSENSUS
WOULD HAVE THE ARRIVAL DURING MONDAY AFTERNOON. INITIALLY THE
SATURATION IS DEEP ENOUGH THAT PRECIP SHOULD BEGIN AS LIGHT SNOW.
BUT INTO THE EVENING...MID LEVELS BEGIN TO DRY OUT SOME AND PRECIP
COULD TRANSITION MORE TO A LIGHT SNOW MIXED WITH OR JUST FREEZING
DRIZZLE. FAIRLY LOW CONFIDENCE AT THIS POINT...SO MAINTAINED JUST
LIGHT SNOW FOR THE ENTIRE DURATION FOR NOW.
PROGRESSIVE PATTERN BRINGS ANOTHER RIDGE OF HIGH PRESSURE ACROSS
THE REGION TUESDAY NIGHT INTO WEDNESDAY AND THEN ANOTHER STORM
SYSTEM WEDNESDAY NIGHT INTO THURSDAY MORNING. MODELS CURRENTLY IN
DECENT AGREEMENT WITH THE TRACK OF THIS LOW GENERALLY RIGHT ACROSS
THE CWA EARLY THURSDAY MORNING. WITH THIS TRACK...TEMPS LIKELY TO
REMAIN FAIRLY STEADY IN THE LOWER/MID 30S WEDNESDAY NIGHT AND
THERMAL PROFILES WOULD SUGGEST PRECIP WOULD BE MAINLY RAIN OR
PERHAPS FREEZING RAIN...IF SURFACE TEMPS REMAINED BELOW FREEZING.
AND ALSO COULD BE SOME SNOW IF THE LOW WERE TO SPEED UP AND/OR
TRACK FURTHER SOUTH. THUS DID NOT GET TOO SPECIFIC WITH PRECIP
TYPE WEDNESDAY NIGHT INTO THURSDAY BUT A WINTRY MIX IS POSSIBLE.
CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR/PATCHY IFR CIGS DEVELOPING PRE-DAWN.
* NORTHEAST WINDS INCREASING QUICKLY TOWARD SUNRISE...AND GUST
NEAR 30 KT AT TIMES LATE MORNING AND AFTERNOON.
* SNOW DEVELOPING EARLY-MID MORNING...WITH MVFR VSBY LIKELY AND
IFR AND SOME ACCUMULATION PROBABLE THROUGH MIDDAY BEFORE
TAPERING TO LIGHT SNOW SHOWERS OR FLURRIES EARLY THIS AFTERNOON.
* MVFR CIGS THIS AFTERNOON INTO THIS EVENING.
RATZER
//DISCUSSION...UPDATED 06Z...
LOW PRESSURE OVER CENTRAL IOWA WILL MOVE SOUTHEAST ACROSS
NORTHEAST MISSOURI AND INTO SOUTHERN ILLINOIS TODAY. NORTHEAST
WINDS WILL INCREASE QUICKLY TOWARD MORNING AS THE SURFACE PRESSURE
GRADIENT TIGHTENS IN RESPONSE TO THE RAPIDLY MOVING LOW PRESSURE
SYSTEM...MAKING FOR WINDY CONDITIONS WITH SUSTAINED SPEEDS 15-20
KT AND GUSTS 25-30 KT DURING THE LATE MORNING AND AFTERNOON HOURS.
WINDS WILL GRADUALLY DIMINISH TONIGHT AS WEAK HIGH PRESSURE
APPROACHES BY MONDAY MORNING.
AN EXTENSIVE AREA OF MVFR AND PATCHY IFR STRATUS OVER
MICHIGAN/WISCONSIN AND LAKE MICHIGAN IS EXPECTED TO SPREAD BACK
ACROSS THE TERMINALS EARLY THIS MORNING AS NORTHEAST WINDS
INCREASE. SNOW CURRENTLY DEPICTED BY RADAR RETURNS OVER SOUTHERN
MINNESOTA AND NORTHERN IOWA WILL SPREAD SOUTHEAST INTO THE REGION
THIS MORNING...WITH THE BULK OF THE HEAVIER SNOW EXPECTED OFF TO
THE SOUTHWEST OF THE TERMINALS. STILL...THE MID-MORNING THROUGH
NOON HOURS SHOULD SEE THE GREATEST PROBABILITY OF MINOR
ACCUMULATIONS AND MVFR/IFR VISIBILITY IN LIGHT SNOW. SNOW SHOULD
TAPER TO LIGHT SNOW SHOWERS AND FLURRIES THIS AFTERNOON.
MVFR STRATOCU LOOKS TO LINGER INTO TONIGHT...THOUGH SHOULD BECOME
THINNER WITH TIME AS DRIER AIR IS DRAWN IN FROM THE NORTHEAST.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM IN CIG TRENDS EARLY THIS MORNING AND IN SNOW
TIMING/IMPACT.
* HIGH IN WIND TRENDS.
* MEDIUM IN CIGS BEYOND THIS EVENING.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...SLIGHT CHANCE -SN IN THE AFTERNOON. MVFR POSSIBLE.
TUESDAY...MVFR CIGS POSSIBLE.
WEDNESDAY...MAINLY VFR DURING THE DAY THEN CHANCE OF -RASN AND
MVFR/IFR AT NIGHT.
THURSDAY...CHANCE OF SNOW. MVFR/IFR POSSIBLE.
FRIDAY...CHANCE OF MVFR CIGS.
IZZI
&&
.MARINE...
127 PM CST
A COLD FRONT WILL BEGIN TO SHIFT SOUTHWARD DOWN LAKE MICHIGAN LATE
THIS AFTERNOON...WITH WINDS EXPECTED TO PICK UP OUT OF THE NORTH
INTO TONIGHT. WINDS OVER THE LAKE WILL THEN CONTINUE TO INCREASE
INTO SUNDAY AS A QUICK MOVING CLIPPER SYSTEM TRACKS SOUTHEASTWARD
ACROSS SOUTHERN ILLINOIS. THIS WILL RESULT IN NORTHEASTERLY WINDS UP
TO 30 KT BY EARLY SUNDAY MORNING ACROSS MOST OF THE LAKE...WITH THE
STRONGEST WINDS EXPECTED ACROSS THE SOUTHERN END OF THE LAKE...WHERE
A FEW GALE FORCE GUSTS TO 35 KT ARE POSSIBLE ON SUNDAY. THIS WILL
RESULT IN WAVES UP TO 10 FEET INTO THE NORTHEAST ILLINOIS SHORES
THROUGH SUNDAY EVENING. THE WINDS WILL QUICKLY ABATE ACROSS THE LAKE
SUNDAY NIGHT AS THE LOW SHIFTS TOWARDS THE EASTERN SEABOARD.
ANOTHER WEAKENING LOW WILL SHIFT SOUTHWARD OVER OR JUST WEST OF THE
LAKE LATE MONDAY AND MONDAY NIGHT. THIS WILL RESULT IN A PERIOD OF
LIGHT SOUTHERLY WINDS OVER THE LAKE DURING THIS PERIOD. LATER IN THE
WEEK ANOTHER LOW IS EXPECTED TO IMPACT THE GREAT LAKES REGION. THIS
SYSTEM STILL HAS THE POTENTIAL TO PRODUCE A PERIOD OF STRONG
SOUTHERLY WINDS WEDNESDAY NIGHT...FOLLOWED BY STRONG NORTHERLY WINDS
THURSDAY INTO FRIDAY.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...6 AM SUNDAY TO 9 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1105 PM CST Sat Jan 24 2015
.UPDATE...
ISSUED AT 846 PM CST SAT JAN 24 2015
Overnite forecast generally on track. 18z models and HRRR indicate
that low-level thermal profile may be conducive for some sleet to
mix with rain prior to 12z in the far NW. Will add wording for
that potential as far east as Peoria.
Still plenty of uncertainty in low-level temperature forecast for
late tonight and Sunday with most models indicate temperatures
near or possibly just above freezing at the surface and warmer
temps around 925 mb through the morning then rapid cooling behind
the expected cliper system during the afternoon and a changeover.
The trend of the solution envelope has also shifted south over the
past few days which if it continues will bring CAA into the
northern counties faster. Still appears that accumulations of an
1"-3" still possible mainly northeast of I-74 with the best
chances of accumulation occurring on elevated and grassy surfaces.
&&
.SHORT TERM...(Tonight)
ISSUED AT 236 PM CST SAT JAN 24 2015
Abundant sunshine occurring across the forecast area this afternoon,
which has allowed temperatures to warm well into the 40s, with some
50 degree readings about to occur in west central Illinois. The
leading edge of the high clouds from our incoming storm system are
about to cross the Mississippi River, and should become more
widespread over our area toward sunset.
Latest surface map shows the low center in central North Dakota. The
12Z models have trended a bit south again with the track, but are in
general agreement with a position in the Quincy area by sunrise
Sunday, and associated warm front extending east across the northern
CWA. With the CWA largely in the warm sector overnight, have shown
only a couple degrees of temperature fall tonight with the entire
area remaining well above freezing. Have updated the alignment and
timing of the PoP`s to focus on the period after midnight, and also
increase them from the west. Higher resolution models start
spreading precipitation in from the west after about 3 am, which
soundings show as rain, although a bit of sleet is hinted at across
the northwest CWA, with a dry wedge between 925 and 850 mb.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 236 PM CST SAT JAN 24 2015
After several days of significant spread and large north/south
swings in the storm track with Sunday`s clipper system, the models
have finally come into better agreement. The current consensus is
kind of a middle ground of the north/south extremes of the past few
days, although it leans more toward the southern tracks that had
been advertised. A more southern track is preferred considering how
much digging the clipper wave still appears to be doing on water
vapor imagery as it is diving into the northern Rockies/Plains.
Would not be surprised to see the ultimate track to be a little
south of the current model consensus, a track which result in an
associated shift of the main snowfall track.
The surface low center should be near the extreme tip of
west-central Illinois at 12Z Sunday, and will quickly race to the
southern tip of Ohio by 06Z Monday. The bulk of the precipitation
with this system should occur during the daylight hours Sunday as a
quick shot of modest isentropic ascent ahead of the wave, and jet
forcing/DPVA as the upper trof axis, swing through.
Measurable precipitation now appears to be a given areawide with
this system, and have boosted PoPs to Categorical (80%+) on Sunday.
The main question is rain versus snow, and how much snow will
accumulate. Temperatures to start the day across most if not all of
the forecast area will be too warm for snow to reach the ground
thanks to the southerly flow ahead of the clipper. Forecast
soundings suggest the low level thermal profile will steadily become
cool enough for a rain to snow transition from northwest to
southeast during the day as cold air wraps in on the north side of
the surface low. The change over should occur around Galesburg near
sunrise, along a Springfield to Champaign line around midday, and
south of I-70 by shortly after sunset. The current track and speed
of change over to snow supports 1-3 inch accumulations along and
north of the I-74 corridor, with an inch or less south of there. Any
lingering snow will quickly come to an end Sunday evening as the
clipper races south/east of the area.
Another wave, much weaker than the first one, will pass north of the
forecast area on Monday. Have started to back down from the already
low snow chances we had over northern portions of the forecast area
with this wave. The lead clipper is expected to develop into a major
east coast storm after it leaves the area, and Monday`s wave is
essentially shearing out into the much stronger system.
A stronger wave coming off the Pacific is expected to move through
the Midwest by Wednesday night and Thursday. At this point, this
system appears warm enough to be mainly a rain producer. Another
system may arrive to start next weekend, but model agreement in the
details is pretty low at this time.
Temperatures through the next week should be at or above normal. The
coolest readings are likely Monday/Tuesday behind the main clipper,
and again Friday/Saturday behind the midweek system.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1105 PM CST SAT JAN 24 2015
Low-level thermal profiles still a challenge as the 00z models
continue to be on the warm side of the current forecast despite
the low tracking a bit further south. Latest water vapor imagery
and upstream observations suggest that the southward trend in the
forecast envelope may continue. However one impact of the further
south trajectory may be to delay post-system low-level CAA. Cold
air remains bottled up over eastern North Dakota, Minnesota, and
northern Wisconsin and is not yet being funneled into the storm.
Will delay switchover of precip from liquid to frozen and confine
a period of possible sleet to KPIA and KBMI.
Gusty north winds still look likely after storm passage Sunday
afternoon as forecasted gradient tightens.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barker
SHORT TERM...Geelhart
LONG TERM...Bak
AVIATION...Barker
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1053 PM EST MON JAN 26 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 152 PM EST MON JAN 26 2015
A QUICK MOVING WEATHER DISTURBANCE WILL PUSH ACROSS ILLINOIS AND
INDIANA THIS EVENING...BRINGING CHANCES FOR SOME LIGHT SNOW THIS
EVENING TO WESTERN PARTS OF CENTRAL INDIANA.
COLD HIGH PRESSURE IS EXPECTED TO ARRIVE ON TUESDAY AND CONTINUE
TO REMAIN IN THE AREA THROUGH WEDNESDAY NIGHT. THIS WILL RESULT IN
DRY WEATHER WITH BELOW NORMAL TEMPERATURES. ANOTHER QUICK MOVING
AREA OF LOW PRESSURE IS EXPECTED TO ARRIVE AND PASS ACROSS CENTRAL
INDIANA ON EARLY THURSDAY MORNING...ONCE AGAIN RESULTING IN CHANCES
FOR PRECIPITATION.
ANOTHER WEAK LOW PRESSURE SYSTEM IS EXPECTED TO PUSH ACROSS THE
REGION THIS WEEKEND...ONCE AGAIN RESULTING IN CHANCES FOR
PRECIPITATION.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1039 PM EST MON JAN 26 2015
UPDATE...
INSERTED MENTION OF PATCHY FREEZING DRIZZLE ACROSS THE WESTERN
PORTIONS OF CENTRAL INDIANA. FREEZING DRIZZLE HAS BEEN REPORTED
UPSTREAM. CONTINUED TO LEAVE FAR NORTHEAST COUNTIES DRY EXCEPT FOR
A FEW FLURRIES. UPDATED GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
MAIN FORECAST CHALLENGE WILL BE PRECIP THIS EVENING. GFS SUGGESTS
THE UPPER WAVE RESPONSIBLE FOR THE ONGOING SNOW OVER ILLINOIS WILL
CONTINUE TO DIVE SSE AMID THE QUICK FLOW ALOFT. HRRR SHOW PRECIP
MAINLY CONTAINED TO THE WESTERN PARTS OF THE FORECAST AREA. TIME
HEIGHTS THIS EVENING SHOW BEST SATURATION IN THE WESTERN AND
SOUTHERN PARTS OF THE FORECAST AREA...WITH LESS MOISTURE AVAILABLE
ACROSS THE NORTHEAST. ISENTROPIC SURFACE SHOWS LITTLE TO NO HELP
AS THIS SYSTEM PASSES. FORECAST SOUNDINGS ACROSS WESTERN INDIANA
CONTINUE TO SHOW GOOD LOW AND MID LEVEL SATURATION THROUGH THE
NIGHT.
THUS WILL RAISE POPS...PARTICULARLY ACROSS THE WESTERN PARTS OF
THE FORECAST AREA...TRENDING TOWARD A FLURRY OR DRY FORECAST ACROSS
THE FAR NORTHEAST. AS FOR TEMPS...CLOUDS ARE EXPECTED THROUGH MUCH
OF THE NIGHT AS THE UPPER WAVE PASSES AND TEMPERATURE ADVECTION IS
NEUTRAL. THUS WILL STICK CLOSE TO A BLEND ON TEMPS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 152 PM EST MON JAN 26 2015
MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE TEMPS INITALLY
FOLLOWED BY PRECIPITATION CHANCES ON THURSDAY.
DRY AND COLD WEATHER IS EXPECTED THROUGH WEDNESDAY DUE TO THE
FOLLOWING REASONS:
SURFACE HIGH PRESSURE BUILDING OUT OF CANADA WILL BUILD ACROSS AND
PASS OVER CENTRAL INDIANA THROUGH WEDNESDAY NIGHT. TIME HEIGHT
SECTIONS THROUGH WEDNESDAY NIGHT CONTINUE TO SHOW A DRY COLUMN
AMID SUBSIDENCE. FORECAST SOUNDINGS AGREE...ONLY SHOWING SOME
SATURATION NEAR 12Z THURSDAY. MEANWHILE ALOFT...A DEEP TROUGH OVER
EASTERN 1/2 OF THE UNITED STATES WILL CONTINUE TO PROVIDE A VERY
COLD AND NW FLOW TO CENTRAL INDIANA. THIS WILL HELP IN RESULTING
IN BELOW NORMAL TEMPERATURES. THUS WITH ONLY A FEW QUICK PASSING
HIGH CLOUDS EXPECTED...WILL TREND TOWARD PARTLY CLOUDY ON TUESDAY
THROUGH WEDNESDAY EVENING...ALONG WITH A BLEND ON TEMPS.
ON LATE WEDNESDAY NIGHT THE GFS INDICATES A WELL ORGANIZED SHORT
WAVE ALOFT PUSHING INTO INDIANA FROM THE WEST. ONCE
AGAIN...FORECAST SOUNDINGS HINT AT LOWER LEVEL SATURATION AHEAD OF
THIS SYSTEM. SOUNDINGS ALSO SHOW WARM AIR ADVECTION IN THE LOWEST
LEVELS THAT WILL ALLOW ANY PRECIP ON THURSDAY MORNING TO FALL AS
RAIN. 300K GFS ISENTROPIC SURFACE SHOWS GOOD UPGLIDE ALONG WITH A
SURGE OF SPECIFIC HUMIDITIES OF 2 G/KG. THUS ROUND OF LIGHT PRECIP
IS EXPECTED. BY THURSDAY AFTERNOON THE UPPER SHORT WAVE LOOKS TO
BE WELL EAST OF INDIANA AND COLD AIR ADVECTION WILL ONCE AGAIN BE
IN PLAY. FORECAST SOUNDINGS SHOW THE SATURATED LOWER PARTS OF THE
COLUMN FALLING BELOW FREEZING...THUS A CHANGE OVER TO SNOW DURING
THE AFTERNOON FOR ANY LINGERING PRECIP LOOKS REASONABLE. HOWEVER
WITH A LACK OF DEEP MOISTURE AND TEH BEST FORCING OFF TO THE
EAST...ANY SNOW AMOUNTS WILL BE QUITE LIGHT.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 250 PM EST MON JAN 26 2015
ONE SYSTEM WILL BE EXITING OUR REGION THURSDAY EVENING...THUS WILL
CONTINUE A SLIGHT CHANCE OF SNOW EAST AND CENTRAL THURSDAY EVENING.
HIGH PRESSURE BEHIND THIS SYSTEM WILL MOVE ACROSS OUR REGION FRIDAY
NIGHT AND IT NOW LOOKS LIKE DRY WEATHER WILL BE THE RULE THROUGH
SATURDAY.
ANOTHER SYSTEM WILL BRING US A CHANCE OF SNOW SATURDAY NIGHT INTO
SUNDAY AS THE MODELS HAVE TRENDED SLOWER WITH THIS SYSTEM.
FINALLY COLDER AND DRY WEATHER WILL BE THE RULE REST OF THE LONG
TERM AS A LONG WAVE TROUGH AMPLIFIES OVER THE EASTERN U.S. THE
MODELS HAVE TRENDED A LITTLE COLDER DURING THIS PERIOD. BUT ALL AND
ALL WENT CLOSE TO A MOS BLEND ON TEMPERATURES.
&&
.AVIATION /DISCUSSION FOR THE 270300Z IND TAF UPDATE/...
ISSUED AT 935 PM EST MON JAN 26 2015
EXTENDED THE FLURRIES THROUGH 06Z BASED ON UPSTREAM OBS AND RADAR.
MAY NEED TO EVENTUALLY THROW SOME FREEZING DRIZZLE IN THERE AS WELL
IF TRENDS CONTINUE. ALSO...WENT WITH VFR CEILINGS AS THERE HAS NOT
BEEN AN MVFR CEILING IN 2 HOURS AND UPSTREAM LAF ALSO IS STILL VFR
AT THIS TIME.
PREVIOUS DISCUSSION FOLLOWS...
IT LOOKS LIKE THE BULK OF THE LIGHT SNOW OR FLURRIES WILL REMAIN
JUST WEST OF IND TONIGHT AS AN UPPER DISTURBANCE SLIDES SOUTHEAST OF
THE AREA. MODELS AND RADAR TRENDS SUGGEST LINGERING POCKETS OF LIGHT
SNOW SHOULD END AT LAF AFTER 02Z...HUF AFTER 04Z AND BMG AFTER 05Z.
WENT WITH MVFR CEILINGS THROUGH THE NIGHT PER MODEL RH TIME SECTIONS
AND OBSERVATIONAL TRENDS...ALTHOUGH BRIEF VFR OR BRIEF IFR IN SNOW
SHOWERS CAN NOT BE RULED OUT. CONDITIONS SHOULD IMPROVE TO VFR AFTER
15Z TUESDAY.
WINDS WILL BE VARIABLE AT 3 KNOTS OR LESS TONIGHT AND NORTHEAST AND
NORTH LESS THAN 8 KNOTS ON TUESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...TDUD
SHORT TERM...PUMA
LONG TERM....JH
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
335 PM EST SUN JAN 25 2015
.SYNOPSIS...
ISSUED AT 331 PM EST SUN JAN 25 2015
A LOW PRESSURE SYSTEM MOVING SOUTH OF THE REGION WILL CONTINUE TO
BRING SNOW TO THE FORECAST AREA THROUGH LATE TONIGHT. WINDS
GUSTING UP TO 30 MPH WILL CAUSE SNOW TO BLOW AND
DRIFT...ESPECIALLY IN THE SOUTHEAST. OTHERWISE...LOW TEMPERATURES
WILL DROP INTO THE SINGLE DIGITS AND TEENS TONIGHT. MONDAY WILL BE
QUIET...WITH PARTLY TO MOSTLY CLOUDY SKIES AND HIGHS IN THE 20S.
&&
.UPDATE...
ISSUED AT 106 PM EST SUN JAN 25 2015
HAVE ISSUED A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW.
EXPECT SNOWFALL AMOUNTS OF 2 TO 5 INCHES COMBINED WITH BLOWING AND
DRIFTING SNOW. MUCH COLDER AIR WAS SPREADING ACROSS THE AREA FROM
THE NORTHEAST. SUSTAINED WINDS HAD INCREASED BEHIND THE FRONT TO
AROUND 20 MPH WITH SOME GUSTS OVER 30 MPH. THE LATEST NCEP HI/RES
SUPPORT BASICALLY 2 TO 5 INCHES OF SNOW OVER AREAS EAST AND SOUTH
OF FT WAYNE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 439 AM EST SUN JAN 25 2015
CHALLENGING SHORT TERM FORECAST AS PCPN TYPE IN QUESTION EARLY TODAY
AND SNOWFALL AMOUNTS WILL DEPEND ON TIMING OF CHANGEOVER TO ALL
SNOW. 00Z MODELS GENERALLY IN GOOD AGREEMENT SYNOPTICALLY WITH
ALMOST ALL SOLUTIONS TAKING SURFACE LOW SOUTHEAST FROM IA THIS
MORNING TO NEAR KEVV BY EARLY AFTERNOON...THEN EAST ACROSS NORTHERN
KENTUCKY TONIGHT. PRECIPITATION WILL SPREAD EAST ACROSS THE LOCAL
AREA TODAY AHEAD AND NORTH OF THE LOW.
STRONG MERIDIONAL JET DIVING SOUTH THROUGH THE PLAINS WILL DRIVE
CLIPPER SYSTEM SOUTHEAST TODAY. LOW LEVEL NORTHEAST FLOW WILL
INCREASE AND THIS WILL BRING COLDER AIR SOUTH HELPING ERODE WARM
LAYER ALOFT AND CHANGE PCPN OVER TO ALL SNOW FROM NORTH TO SOUTH.
THERE IS A BIT OF A CONCERN THOUGH AS MOST HIRES GUIDANCE HAS BEEN
ANYWHERE FROM 2 TO 5 DEGREES TOO WARM WITH SFC TEMPS EARLY THIS
MORNING ACROSS LOWER MICHIGAN. AS OF 08Z THOUGH WE ARE FINALLY
STARTING TO SEE A THERMAL RESPONSE IN SFC OBS WITH TEMPS DROPPING A
FEW DEGREES. THIS IS ENCOURAGING BUT STILL CONCERNED THAT MODELS ARE
A FEW HOURS TOO FAST BRINGING THE COLDER AIR SOUTH WHICH IN TURN
COULD DELAY CHANGEOVER IN FAR SOUTH UNTIL MID AFTERNOON.
HRRR...RUC AND LAMP GUIDANCE HAVE BEEN PLAYING CATCHUP ALL NIGHT.
HAVE MANUALLY ADJUSTED HOURLY SFC TEMPS WITH SLIGHTLY SLOWER COOLING
THAN RUC GUIDANCE SUGGESTS. DO EXPECT COLDER AIR TO QUICKLY MOVE SOUTH
ONCE CLIPPER GETS CLOSER AND PRESSURE GRADIENT TIGHTENS LATER THIS
MORNING.
MEANWHILE...LACK OF LOW CLOUDS ALONG WITH LIGHT WINDS IN THE WESTERN
CWA HAS ALLOWED SFC TEMPS THERE TO DROP TO AROUND FREEZING WITH SOME
FOG DEVELOPMENT. DO EXPECT TEMPS HERE TO RISE ABOVE FREEZING AHEAD
OF PCPN ARRIVAL WITH SFC TEMPS ACROSS CENTRAL ILLINOIS IN THE MID TO
UPPER 30S EARLY THIS MORNING. THIS COMBINED WITH 1000-850MB WARM
TONGUE OF 2 TO 4C DEPICTED BY HIRES GUIDANCE SUGGEST A MIX OF RAIN
AND SNOW UNTIL WARM LAYER IS FULLY ERODED. TOP DOWN METHOD ACTUALLY
DEPICTS A FEW HOURS OF JUST RAIN ACROSS THE EXTREME SOUTHERN CWA
LATE MORNING INTO EARLY AFTERNOON BEFORE FULLY CHANGING OVER TO
SNOW.
THE FARTHER SOUTH TRACK OF CLIPPER HAS ALSO MEANT A SOUTHWARD SHIFT
IN STRONGEST FORCING AND HEAVIEST PCPN AXIS. STRONGEST FGEN FORCING
AND BANDING POTENTIAL NOW LOOKS TO BE JUST SOUTH OF OUR AREA. THIS
COMBINED WITH MIXED PCPN AND DELAYED CHANGEOVER TO SNOW HAS LED TO
DECREASED SNOW AMOUNTS OVER THE ENTIRE AREA. MODEL QPF NOW GENERALLY
AROUND A QUARTER INCH SOUTH OF THE US24 CORRIDOR. MIXING RATIOS OF 3
TO 4 G/KG AND PWATS AROUND 0.5 INCHES STILL A CONCERN...ESPECIALLY
IF ANY BANDING DEVELOPS. STILL EXPECT A SWATH OF 2 TO 4 INCHES
ACROSS THE FAR SOUTH AND THE HIGHER END AMOUNTS SOUTHEAST WHERE
PIVOT POINT AND SNOW THIS EVENING TAKE ADVANTAGE OF SLIGHTLY BETTER
RATIOS. ISOLATED AMOUNTS OF 5 INCHES NOT OUT OF QUESTION IF BANDING
CLIPS THIS AREA. WITH THIS BEING MID WINTER AND EXPECTATION OF A WET
2 TO 4 INCHES WITH LOW IMPACTS FOR TRAVEL HAVE OPTED TO NOT ISSUE
ANY ADVISORY AT THIS TIME. WILL HIGHLIGHT SNOWFALL IN AN SPS AND
HWO.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 439 AM EST SUN JAN 25 2015
NEXT CLIPPER-TYPE SYSTEM TO POTENTIALLY IMPACT THE AREA WILL ARRIVE
ON MONDAY NIGHT. FORCING MECHANISM IS REALLY MORE ACCURATELY
DESCRIBED AS JUST A THIN RIBBON OF CYCLONIC SHEAR VORTICITY ON THE
UPWIND SIDE OF DEEPENING EAST COAST TROUGH. AS SUCH...FORCING FOR
ASCENT IS PRETTY MINUSCULE AND RESIDENT AIRMASS...AT LEAST IN THE
MIDLEVELS...IS VERY DRY. WEAK 285K ISENTROPIC ASCENT AND SUBTLE LOW
LEVEL MOISTURE ADVECTION MAY GENERATE SOME VERY LIGHT SNOW BUT
LITTLE TO NO ACCUMULATION IS EXPECTED. PREFERENCE STILL LIES WITH
THE DRIER/FURTHER SOUTHWEST CANADIAN AND EUROPEAN SOLUTIONS.
ACTUALLY AM A LITTLE CONCERNED ABOUT POTENTIAL FOR FREEZING DRIZZLE.
NAM AND GFS FORECAST SOUNDINGS INDICATE DEEP ENOUGH SATURATION TO
SUPPORT ICE NUCLEATION BUT JUST BARELY AND AM CONCERNED THEY ARE
OVERDOING THE EXTENT OF LOW LEVEL MOISTURE AND ASCENT. WILL HOLD OFF
ON INCLUDING IN THE FORECAST FOR NOW GIVEN THE HIGHER PROBABILITY
THAT ANY PRECIPITATION THAT DOES MANAGE TO OCCUR WILL DO SO IN AN
ENVIRONMENT ADEQUATELY SATURATED TO SUPPORT ICE NUCLEI AND OTHER
LOCATIONS WILL SIMPLY REMAIN DRY. SOMETHING TO KEEP AN EYE ON THOUGH.
MORE IMPRESSIVE WAVE IS SET TO PLOW OVER THE WEST COAST RIDGE ON
WEDNESDAY. THIS ACTUALLY FORCES DOWNSTREAM HEIGHT RISES LOCALLY WITH
A BRIEF RETURN TO SOUTHWEST FLOW AND WARMER TEMPERATURES. SHORTWAVE
WILL THEN ENTER OUR REGION ON THURSDAY WITH THE NEXT DECENT CHANCE
OF PRECIP. NEEDLESS TO SAY....FORECAST CONFIDENCE IN EXACT TRACK IS
LOW AND THIS WILL HAVE A LARGE IMPACT ON THERMAL PROFILES AND QPF
TOTALS. CURRENTLY APPEARS THE BEST CHANCE FOR SIGNIFICANT SNOW WILL
REMAIN OVER CENTRAL MICHIGAN WITH MORE OF A MIX ACROSS NORTHERN
INDIANA AND OHIO. THIS WILL UNDOUBTEDLY CHANGE AS WE GET CLOSER
THOUGH.
AFTER A COLD START ON MONDAY...TEMPERATURES WILL QUICKLY RETURN TO
VALUES AT OR ABOVE NORMAL FOR THE MIDWEEK PERIOD. COOLER TEMPS
EXPECTED AFTER THURSDAY`S WAVE BUT MUCH COLDER CONDITIONS STILL
APPEAR POSSIBLE EARLY NEXT WEEK AFTER A THIRD WAVE/ARCTIC FRONT
PASSES OVER THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 106 PM EST SUN JAN 25 2015
THE PRECIPITATION HAS BECOME ALL SNOW AT BOTH TERMINALS WITH
STRONG COLD AIR ADVECTION FROM THE NORTHEAST. HAVE ADDED THE
MENTION OF BLOWING SNOW AT FT WAYNE WITH STRONGER WINDS EXPECTED.
OTHERWISE...HAVE MADE SOME MINOR ADJUSTMENTS TO THE TIMING OF THE
SNOW AND THE IMPROVEMENT TO VFR CONDITIONS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR INZ026-
027-032>034.
MI...NONE.
OH...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR OHZ015-
016-024-025.
LM...NONE.
&&
$$
UPDATE...SKIPPER
SYNOPSIS...MCD
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...SKIPPER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
132 PM EST SUN JAN 25 2015
.SYNOPSIS...
ISSUED AT 430 AM EST SUN JAN 25 2015
AN AREA OF LOW PRESSURE WILL MOVE FROM SOUTHERN IOWA THIS MORNING
TO SOUTHWEST INDIANA BY MID AFTERNOON AND THEN THROUGH KENTUCKY
TONIGHT. THIS CLIPPER SYSTEM WILL SPREAD ACCUMULATING SNOW OVER
PARTS OF NORTH CENTRAL AND NORTHERN INDIANA AND NORTHWEST OHIO
TODAY WITH RAIN SOUTH OF THIS AREA. HIGH TEMPERATURES WILL
OCCUR THIS MORNING WITH READINGS RANGING FROM THE LOWER 20S NORTH
TO UPPER 30S SOUTH. EXPECT FALLING TEMPERATURES DURING THE DAY.
LOWS TONIGHT WILL BE VERY COLD WITH SINGLE DIGITS ACROSS THE NORTH
AND TEENS SOUTH.
&&
.UPDATE...
ISSUED AT 106 PM EST SUN JAN 25 2015
HAVE ISSUED A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW.
EXPECT SNOWFALL AMOUNTS OF 2 TO 5 INCHES COMBINED WITH BLOWING AND
DRIFTING SNOW. MUCH COLDER AIR WAS SPREADING ACROSS THE AREA FROM
THE NORTHEAST. SUSTAINED WINDS HAD INCREASED BEHIND THE FRONT TO
AROUND 20 MPH WITH SOME GUSTS OVER 30 MPH. THE LATEST NCEP HI/RES
SUPPORT BASICALLY 2 TO 5 INCHES OF SNOW OVER AREAS EAST AND SOUTH
OF FT WAYNE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 439 AM EST SUN JAN 25 2015
CHALLENGING SHORT TERM FORECAST AS PCPN TYPE IN QUESTION EARLY TODAY
AND SNOWFALL AMOUNTS WILL DEPEND ON TIMING OF CHANGEOVER TO ALL
SNOW. 00Z MODELS GENERALLY IN GOOD AGREEMENT SYNOPTICALLY WITH
ALMOST ALL SOLUTIONS TAKING SURFACE LOW SOUTHEAST FROM IA THIS
MORNING TO NEAR KEVV BY EARLY AFTERNOON...THEN EAST ACROSS NORTHERN
KENTUCKY TONIGHT. PRECIPITATION WILL SPREAD EAST ACROSS THE LOCAL
AREA TODAY AHEAD AND NORTH OF THE LOW.
STRONG MERIDIONAL JET DIVING SOUTH THROUGH THE PLAINS WILL DRIVE
CLIPPER SYSTEM SOUTHEAST TODAY. LOW LEVEL NORTHEAST FLOW WILL
INCREASE AND THIS WILL BRING COLDER AIR SOUTH HELPING ERODE WARM
LAYER ALOFT AND CHANGE PCPN OVER TO ALL SNOW FROM NORTH TO SOUTH.
THERE IS A BIT OF A CONCERN THOUGH AS MOST HIRES GUIDANCE HAS BEEN
ANYWHERE FROM 2 TO 5 DEGREES TOO WARM WITH SFC TEMPS EARLY THIS
MORNING ACROSS LOWER MICHIGAN. AS OF 08Z THOUGH WE ARE FINALLY
STARTING TO SEE A THERMAL RESPONSE IN SFC OBS WITH TEMPS DROPPING A
FEW DEGREES. THIS IS ENCOURAGING BUT STILL CONCERNED THAT MODELS ARE
A FEW HOURS TOO FAST BRINGING THE COLDER AIR SOUTH WHICH IN TURN
COULD DELAY CHANGEOVER IN FAR SOUTH UNTIL MID AFTERNOON.
HRRR...RUC AND LAMP GUIDANCE HAVE BEEN PLAYING CATCHUP ALL NIGHT.
HAVE MANUALLY ADJUSTED HOURLY SFC TEMPS WITH SLIGHTLY SLOWER COOLING
THAN RUC GUIDANCE SUGGESTS. DO EXPECT COLDER AIR TO QUICKLY MOVE SOUTH
ONCE CLIPPER GETS CLOSER AND PRESSURE GRADIENT TIGHTENS LATER THIS
MORNING.
MEANWHILE...LACK OF LOW CLOUDS ALONG WITH LIGHT WINDS IN THE WESTERN
CWA HAS ALLOWED SFC TEMPS THERE TO DROP TO AROUND FREEZING WITH SOME
FOG DEVELOPMENT. DO EXPECT TEMPS HERE TO RISE ABOVE FREEZING AHEAD
OF PCPN ARRIVAL WITH SFC TEMPS ACROSS CENTRAL ILLINOIS IN THE MID TO
UPPER 30S EARLY THIS MORNING. THIS COMBINED WITH 1000-850MB WARM
TONGUE OF 2 TO 4C DEPICTED BY HIRES GUIDANCE SUGGEST A MIX OF RAIN
AND SNOW UNTIL WARM LAYER IS FULLY ERODED. TOP DOWN METHOD ACTUALLY
DEPICTS A FEW HOURS OF JUST RAIN ACROSS THE EXTREME SOUTHERN CWA
LATE MORNING INTO EARLY AFTERNOON BEFORE FULLY CHANGING OVER TO
SNOW.
THE FARTHER SOUTH TRACK OF CLIPPER HAS ALSO MEANT A SOUTHWARD SHIFT
IN STRONGEST FORCING AND HEAVIEST PCPN AXIS. STRONGEST FGEN FORCING
AND BANDING POTENTIAL NOW LOOKS TO BE JUST SOUTH OF OUR AREA. THIS
COMBINED WITH MIXED PCPN AND DELAYED CHANGEOVER TO SNOW HAS LED TO
DECREASED SNOW AMOUNTS OVER THE ENTIRE AREA. MODEL QPF NOW GENERALLY
AROUND A QUARTER INCH SOUTH OF THE US24 CORRIDOR. MIXING RATIOS OF 3
TO 4 G/KG AND PWATS AROUND 0.5 INCHES STILL A CONCERN...ESPECIALLY
IF ANY BANDING DEVELOPS. STILL EXPECT A SWATH OF 2 TO 4 INCHES
ACROSS THE FAR SOUTH AND THE HIGHER END AMOUNTS SOUTHEAST WHERE
PIVOT POINT AND SNOW THIS EVENING TAKE ADVANTAGE OF SLIGHTLY BETTER
RATIOS. ISOLATED AMOUNTS OF 5 INCHES NOT OUT OF QUESTION IF BANDING
CLIPS THIS AREA. WITH THIS BEING MID WINTER AND EXPECTATION OF A WET
2 TO 4 INCHES WITH LOW IMPACTS FOR TRAVEL HAVE OPTED TO NOT ISSUE
ANY ADVISORY AT THIS TIME. WILL HIGHLIGHT SNOWFALL IN AN SPS AND
HWO.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 439 AM EST SUN JAN 25 2015
NEXT CLIPPER-TYPE SYSTEM TO POTENTIALLY IMPACT THE AREA WILL ARRIVE
ON MONDAY NIGHT. FORCING MECHANISM IS REALLY MORE ACCURATELY
DESCRIBED AS JUST A THIN RIBBON OF CYCLONIC SHEAR VORTICITY ON THE
UPWIND SIDE OF DEEPENING EAST COAST TROUGH. AS SUCH...FORCING FOR
ASCENT IS PRETTY MINUSCULE AND RESIDENT AIRMASS...AT LEAST IN THE
MIDLEVELS...IS VERY DRY. WEAK 285K ISENTROPIC ASCENT AND SUBTLE LOW
LEVEL MOISTURE ADVECTION MAY GENERATE SOME VERY LIGHT SNOW BUT
LITTLE TO NO ACCUMULATION IS EXPECTED. PREFERENCE STILL LIES WITH
THE DRIER/FURTHER SOUTHWEST CANADIAN AND EUROPEAN SOLUTIONS.
ACTUALLY AM A LITTLE CONCERNED ABOUT POTENTIAL FOR FREEZING DRIZZLE.
NAM AND GFS FORECAST SOUNDINGS INDICATE DEEP ENOUGH SATURATION TO
SUPPORT ICE NUCLEATION BUT JUST BARELY AND AM CONCERNED THEY ARE
OVERDOING THE EXTENT OF LOW LEVEL MOISTURE AND ASCENT. WILL HOLD OFF
ON INCLUDING IN THE FORECAST FOR NOW GIVEN THE HIGHER PROBABILITY
THAT ANY PRECIPITATION THAT DOES MANAGE TO OCCUR WILL DO SO IN AN
ENVIRONMENT ADEQUATELY SATURATED TO SUPPORT ICE NUCLEI AND OTHER
LOCATIONS WILL SIMPLY REMAIN DRY. SOMETHING TO KEEP AN EYE ON THOUGH.
MORE IMPRESSIVE WAVE IS SET TO PLOW OVER THE WEST COAST RIDGE ON
WEDNESDAY. THIS ACTUALLY FORCES DOWNSTREAM HEIGHT RISES LOCALLY WITH
A BRIEF RETURN TO SOUTHWEST FLOW AND WARMER TEMPERATURES. SHORTWAVE
WILL THEN ENTER OUR REGION ON THURSDAY WITH THE NEXT DECENT CHANCE
OF PRECIP. NEEDLESS TO SAY....FORECAST CONFIDENCE IN EXACT TRACK IS
LOW AND THIS WILL HAVE A LARGE IMPACT ON THERMAL PROFILES AND QPF
TOTALS. CURRENTLY APPEARS THE BEST CHANCE FOR SIGNIFICANT SNOW WILL
REMAIN OVER CENTRAL MICHIGAN WITH MORE OF A MIX ACROSS NORTHERN
INDIANA AND OHIO. THIS WILL UNDOUBTEDLY CHANGE AS WE GET CLOSER
THOUGH.
AFTER A COLD START ON MONDAY...TEMPERATURES WILL QUICKLY RETURN TO
VALUES AT OR ABOVE NORMAL FOR THE MIDWEEK PERIOD. COOLER TEMPS
EXPECTED AFTER THURSDAY`S WAVE BUT MUCH COLDER CONDITIONS STILL
APPEAR POSSIBLE EARLY NEXT WEEK AFTER A THIRD WAVE/ARCTIC FRONT
PASSES OVER THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 106 PM EST SUN JAN 25 2015
THE PRECIPITATION HAS BECOME ALL SNOW AT BOTH TERMINALS WITH
STRONG COLD AIR ADVECTION FROM THE NORTHEAST. HAVE ADDED THE
MENTION OF BLOWING SNOW AT FT WAYNE WITH STRONGER WINDS EXPECTED.
OTHERWISE...HAVE MADE SOME MINOR ADJUSTMENTS TO THE TIMING OF THE
SNOW AND THE IMPROVEMENT TO VFR CONDITIONS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR INZ026-
027-032>034.
MI...NONE.
OH...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR OHZ015-
016-024-025.
LM...NONE.
&&
$$
UPDATE...SKIPPER
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...SKIPPER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
636 AM EST SUN JAN 25 2015
.SYNOPSIS...
ISSUED AT 430 AM EST SUN JAN 25 2015
AN AREA OF LOW PRESSURE WILL MOVE FROM SOUTHERN IOWA THIS MORNING
TO SOUTHWEST INDIANA BY MID AFTERNOON AND THEN THROUGH KENTUCKY
TONIGHT. THIS CLIPPER SYSTEM WILL SPREAD ACCUMULATING SNOW OVER
PARTS OF NORTH CENTRAL AND NORTHERN INDIANA AND NORTHWEST OHIO
TODAY WITH RAIN SOUTH OF THIS AREA. HIGH TEMPERATURES WILL
OCCUR THIS MORNING WITH READINGS RANGING FROM THE LOWER 20S NORTH
TO UPPER 30S SOUTH. EXPECT FALLING TEMPERATURES DURING THE DAY.
LOWS TONIGHT WILL BE VERY COLD WITH SINGLE DIGITS ACROSS THE NORTH
AND TEENS SOUTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 439 AM EST SUN JAN 25 2015
CHALLENGING SHORT TERM FORECAST AS PCPN TYPE IN QUESTION EARLY TODAY
AND SNOWFALL AMOUNTS WILL DEPEND ON TIMING OF CHANGEOVER TO ALL
SNOW. 00Z MODELS GENERALLY IN GOOD AGREEMENT SYNOPTICALLY WITH
ALMOST ALL SOLUTIONS TAKING SURFACE LOW SOUTHEAST FROM IA THIS
MORNING TO NEAR KEVV BY EARLY AFTERNOON...THEN EAST ACROSS NORTHERN
KENTUCKY TONIGHT. PRECIPITATION WILL SPREAD EAST ACROSS THE LOCAL
AREA TODAY AHEAD AND NORTH OF THE LOW.
STRONG MERIDIONAL JET DIVING SOUTH THROUGH THE PLAINS WILL DRIVE
CLIPPER SYSTEM SOUTHEAST TODAY. LOW LEVEL NORTHEAST FLOW WILL
INCREASE AND THIS WILL BRING COLDER AIR SOUTH HELPING ERODE WARM
LAYER ALOFT AND CHANGE PCPN OVER TO ALL SNOW FROM NORTH TO SOUTH.
THERE IS A BIT OF A CONCERN THOUGH AS MOST HIRES GUIDANCE HAS BEEN
ANYWHERE FROM 2 TO 5 DEGREES TOO WARM WITH SFC TEMPS EARLY THIS
MORNING ACROSS LOWER MICHIGAN. AS OF 08Z THOUGH WE ARE FINALLY
STARTING TO SEE A THERMAL RESPONSE IN SFC OBS WITH TEMPS DROPPING A
FEW DEGREES. THIS IS ENCOURAGING BUT STILL CONCERNED THAT MODELS ARE
A FEW HOURS TOO FAST BRINGING THE COLDER AIR SOUTH WHICH IN TURN
COULD DELAY CHANGEOVER IN FAR SOUTH UNTIL MID AFTERNOON.
HRRR...RUC AND LAMP GUIDANCE HAVE BEEN PLAYING CATCHUP ALL NIGHT.
HAVE MANUALLY ADJUSTED HOURLY SFC TEMPS WITH SLIGHTLY SLOWER COOLING
THAN RUC GUIDANCE SUGGESTS. DO EXPECT COLDER AIR TO QUICKLY MOVE SOUTH
ONCE CLIPPER GETS CLOSER AND PRESSURE GRADIENT TIGHTENS LATER THIS
MORNING.
MEANWHILE...LACK OF LOW CLOUDS ALONG WITH LIGHT WINDS IN THE WESTERN
CWA HAS ALLOWED SFC TEMPS THERE TO DROP TO AROUND FREEZING WITH SOME
FOG DEVELOPMENT. DO EXPECT TEMPS HERE TO RISE ABOVE FREEZING AHEAD
OF PCPN ARRIVAL WITH SFC TEMPS ACROSS CENTRAL ILLINOIS IN THE MID TO
UPPER 30S EARLY THIS MORNING. THIS COMBINED WITH 1000-850MB WARM
TONGUE OF 2 TO 4C DEPICTED BY HIRES GUIDANCE SUGGEST A MIX OF RAIN
AND SNOW UNTIL WARM LAYER IS FULLY ERODED. TOP DOWN METHOD ACTUALLY
DEPICTS A FEW HOURS OF JUST RAIN ACROSS THE EXTREME SOUTHERN CWA
LATE MORNING INTO EARLY AFTERNOON BEFORE FULLY CHANGING OVER TO
SNOW.
THE FARTHER SOUTH TRACK OF CLIPPER HAS ALSO MEANT A SOUTHWARD SHIFT
IN STRONGEST FORCING AND HEAVIEST PCPN AXIS. STRONGEST FGEN FORCING
AND BANDING POTENTIAL NOW LOOKS TO BE JUST SOUTH OF OUR AREA. THIS
COMBINED WITH MIXED PCPN AND DELAYED CHANGEOVER TO SNOW HAS LED TO
DECREASED SNOW AMOUNTS OVER THE ENTIRE AREA. MODEL QPF NOW GENERALLY
AROUND A QUARTER INCH SOUTH OF THE US24 CORRIDOR. MIXING RATIOS OF 3
TO 4 G/KG AND PWATS AROUND 0.5 INCHES STILL A CONCERN...ESPECIALLY
IF ANY BANDING DEVELOPS. STILL EXPECT A SWATH OF 2 TO 4 INCHES
ACROSS THE FAR SOUTH AND THE HIGHER END AMOUNTS SOUTHEAST WHERE
PIVOT POINT AND SNOW THIS EVENING TAKE ADVANTAGE OF SLIGHTLY BETTER
RATIOS. ISOLATED AMOUNTS OF 5 INCHES NOT OUT OF QUESTION IF BANDING
CLIPS THIS AREA. WITH THIS BEING MID WINTER AND EXPECTATION OF A WET
2 TO 4 INCHES WITH LOW IMPACTS FOR TRAVEL HAVE OPTED TO NOT ISSUE
ANY ADVISORY AT THIS TIME. WILL HIGHLIGHT SNOWFALL IN AN SPS AND
HWO.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 439 AM EST SUN JAN 25 2015
NEXT CLIPPER-TYPE SYSTEM TO POTENTIALLY IMPACT THE AREA WILL ARRIVE
ON MONDAY NIGHT. FORCING MECHANISM IS REALLY MORE ACCURATELY
DESCRIBED AS JUST A THIN RIBBON OF CYCLONIC SHEAR VORTICITY ON THE
UPWIND SIDE OF DEEPENING EAST COAST TROUGH. AS SUCH...FORCING FOR
ASCENT IS PRETTY MINUSCULE AND RESIDENT AIRMASS...AT LEAST IN THE
MIDLEVELS...IS VERY DRY. WEAK 285K ISENTROPIC ASCENT AND SUBTLE LOW
LEVEL MOISTURE ADVECTION MAY GENERATE SOME VERY LIGHT SNOW BUT
LITTLE TO NO ACCUMULATION IS EXPECTED. PREFERENCE STILL LIES WITH
THE DRIER/FURTHER SOUTHWEST CANADIAN AND EUROPEAN SOLUTIONS.
ACTUALLY AM A LITTLE CONCERNED ABOUT POTENTIAL FOR FREEZING DRIZZLE.
NAM AND GFS FORECAST SOUNDINGS INDICATE DEEP ENOUGH SATURATION TO
SUPPORT ICE NUCLEATION BUT JUST BARELY AND AM CONCERNED THEY ARE
OVERDOING THE EXTENT OF LOW LEVEL MOISTURE AND ASCENT. WILL HOLD OFF
ON INCLUDING IN THE FORECAST FOR NOW GIVEN THE HIGHER PROBABILITY
THAT ANY PRECIPITATION THAT DOES MANAGE TO OCCUR WILL DO SO IN AN
ENVIRONMENT ADEQUATELY SATURATED TO SUPPORT ICE NUCLEI AND OTHER
LOCATIONS WILL SIMPLY REMAIN DRY. SOMETHING TO KEEP AN EYE ON THOUGH.
MORE IMPRESSIVE WAVE IS SET TO PLOW OVER THE WEST COAST RIDGE ON
WEDNESDAY. THIS ACTUALLY FORCES DOWNSTREAM HEIGHT RISES LOCALLY WITH
A BRIEF RETURN TO SOUTHWEST FLOW AND WARMER TEMPERATURES. SHORTWAVE
WILL THEN ENTER OUR REGION ON THURSDAY WITH THE NEXT DECENT CHANCE
OF PRECIP. NEEDLESS TO SAY....FORECAST CONFIDENCE IN EXACT TRACK IS
LOW AND THIS WILL HAVE A LARGE IMPACT ON THERMAL PROFILES AND QPF
TOTALS. CURRENTLY APPEARS THE BEST CHANCE FOR SIGNIFICANT SNOW WILL
REMAIN OVER CENTRAL MICHIGAN WITH MORE OF A MIX ACROSS NORTHERN
INDIANA AND OHIO. THIS WILL UNDOUBTEDLY CHANGE AS WE GET CLOSER
THOUGH.
AFTER A COLD START ON MONDAY...TEMPERATURES WILL QUICKLY RETURN TO
VALUES AT OR ABOVE NORMAL FOR THE MIDWEEK PERIOD. COOLER TEMPS
EXPECTED AFTER THURSDAY`S WAVE BUT MUCH COLDER CONDITIONS STILL
APPEAR POSSIBLE EARLY NEXT WEEK AFTER A THIRD WAVE/ARCTIC FRONT
PASSES OVER THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 632 AM EST SUN JAN 25 2015
NOT MUCH CHANGE IN THINKING FOR LATEST TAF PACKAGE. MVFR AND IFR
CONDITIONS WERE DEVELOPING ACROSS THE REGION AND EXPECT TERMINALS
TO DROP THROUGH THE MORNING. LIGHT SNOW WILL SPREAD ACROSS TAF
SITES MID TO LATE MORNING. KSBN REMAINS ON NORTHERN FRINGE OF PCPN
SHIELD WHILE KFWA DEEPER INTO PCPN. COULD BE A BRIEF PERIOD OF
RAIN OR SLEET TO MIX WITH SNOW AT KFWA BUT EXPECT TO BE SHORT
DURATION IF AT ALL. NORTHEAST WINDS WILL INCREASE TODAY WITH 10 TO 20
KNOTS EXPECTED. PCPN TO DIMINISH LATE AFTERNOON AT KSBN AND EARLY
EVENING AT KFWA WITH PARTIAL CLEARING POSSIBLE OVERNIGHT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
440 AM EST SUN JAN 25 2015
.SYNOPSIS...
ISSUED AT 430 AM EST SUN JAN 25 2015
AN AREA OF LOW PRESSURE WILL MOVE FROM SOUTHERN IOWA THIS MORNING
TO SOUTHWEST INDIANA BY MID AFTERNOON AND THEN THROUGH KENTUCKY
TONIGHT. THIS CLIPPER SYSTEM WILL SPREAD ACCUMULATING SNOW OVER
PARTS OF NORTH CENTRAL AND NORTHERN INDIANA AND NORTHWEST OHIO
TODAY WITH RAIN SOUTH OF THIS AREA. HIGH TEMPERATURES WILL
OCCUR THIS MORNING WITH READINGS RANGING FROM THE LOWER 20S NORTH
TO UPPER 30S SOUTH. EXPECT FALLING TEMPERATURES DURING THE DAY.
LOWS TONIGHT WILL BE VERY COLD WITH SINGLE DIGITS ACROSS THE NORTH
AND TEENS SOUTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 439 AM EST SUN JAN 25 2015
CHALLENGING SHORT TERM FORECAST AS PCPN TYPE IN QUESTION EARLY TODAY
AND SNOWFALL AMOUNTS WILL DEPEND ON TIMING OF CHANGEOVER TO ALL
SNOW. 00Z MODELS GENERALLY IN GOOD AGREEMENT SYNOPTICALLY WITH
ALMOST ALL SOLUTIONS TAKING SURFACE LOW SOUTHEAST FROM IA THIS
MORNING TO NEAR KEVV BY EARLY AFTERNOON...THEN EAST ACROSS NORTHERN
KENTUCKY TONIGHT. PRECIPITATION WILL SPREAD EAST ACROSS THE LOCAL
AREA TODAY AHEAD AND NORTH OF THE LOW.
STRONG MERIDIONAL JET DIVING SOUTH THROUGH THE PLAINS WILL DRIVE
CLIPPER SYSTEM SOUTHEAST TODAY. LOW LEVEL NORTHEAST FLOW WILL
INCREASE AND THIS WILL BRING COLDER AIR SOUTH HELPING ERODE WARM
LAYER ALOFT AND CHANGE PCPN OVER TO ALL SNOW FROM NORTH TO SOUTH.
THERE IS A BIT OF A CONCERN THOUGH AS MOST HIRES GUIDANCE HAS BEEN
ANYWHERE FROM 2 TO 5 DEGREES TOO WARM WITH SFC TEMPS EARLY THIS
MORNING ACROSS LOWER MICHIGAN. AS OF 08Z THOUGH WE ARE FINALLY
STARTING TO SEE A THERMAL RESPONSE IN SFC OBS WITH TEMPS DROPPING A
FEW DEGREES. THIS IS ENCOURAGING BUT STILL CONCERNED THAT MODELS ARE
A FEW HOURS TOO FAST BRINGING THE COLDER AIR SOUTH WHICH IN TURN
COULD DELAY CHANGEOVER IN FAR SOUTH UNTIL MID AFTERNOON.
HRRR...RUC AND LAMP GUIDANCE HAVE BEEN PLAYING CATCHUP ALL NIGHT.
HAVE MANUALLY ADJUSTED HOURLY SFC TEMPS WITH SLIGHTLY SLOWER COOLING
THAN RUC GUIDANCE SUGGESTS. DO EXPECT COLDER AIR TO QUICKLY MOVE SOUTH
ONCE CLIPPER GETS CLOSER AND PRESSURE GRADIENT TIGHTENS LATER THIS
MORNING.
MEANWHILE...LACK OF LOW CLOUDS ALONG WITH LIGHT WINDS IN THE WESTERN
CWA HAS ALLOWED SFC TEMPS THERE TO DROP TO AROUND FREEZING WITH SOME
FOG DEVELOPMENT. DO EXPECT TEMPS HERE TO RISE ABOVE FREEZING AHEAD
OF PCPN ARRIVAL WITH SFC TEMPS ACROSS CENTRAL ILLINOIS IN THE MID TO
UPPER 30S EARLY THIS MORNING. THIS COMBINED WITH 1000-850MB WARM
TONGUE OF 2 TO 4C DEPICTED BY HIRES GUIDANCE SUGGEST A MIX OF RAIN
AND SNOW UNTIL WARM LAYER IS FULLY ERODED. TOP DOWN METHOD ACTUALLY
DEPICTS A FEW HOURS OF JUST RAIN ACROSS THE EXTREME SOUTHERN CWA
LATE MORNING INTO EARLY AFTERNOON BEFORE FULLY CHANGING OVER TO
SNOW.
THE FARTHER SOUTH TRACK OF CLIPPER HAS ALSO MEANT A SOUTHWARD SHIFT
IN STRONGEST FORCING AND HEAVIEST PCPN AXIS. STRONGEST FGEN FORCING
AND BANDING POTENTIAL NOW LOOKS TO BE JUST SOUTH OF OUR AREA. THIS
COMBINED WITH MIXED PCPN AND DELAYED CHANGEOVER TO SNOW HAS LED TO
DECREASED SNOW AMOUNTS OVER THE ENTIRE AREA. MODEL QPF NOW GENERALLY
AROUND A QUARTER INCH SOUTH OF THE US24 CORRIDOR. MIXING RATIOS OF 3
TO 4 G/KG AND PWATS AROUND 0.5 INCHES STILL A CONCERN...ESPECIALLY
IF ANY BANDING DEVELOPS. STILL EXPECT A SWATH OF 2 TO 4 INCHES
ACROSS THE FAR SOUTH AND THE HIGHER END AMOUNTS SOUTHEAST WHERE
PIVOT POINT AND SNOW THIS EVENING TAKE ADVANTAGE OF SLIGHTLY BETTER
RATIOS. ISOLATED AMOUNTS OF 5 INCHES NOT OUT OF QUESTION IF BANDING
CLIPS THIS AREA. WITH THIS BEING MID WINTER AND EXPECTATION OF A WET
2 TO 4 INCHES WITH LOW IMPACTS FOR TRAVEL HAVE OPTED TO NOT ISSUE
ANY ADVISORY AT THIS TIME. WILL HIGHLIGHT SNOWFALL IN AN SPS AND
HWO.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 439 AM EST SUN JAN 25 2015
NEXT CLIPPER-TYPE SYSTEM TO POTENTIALLY IMPACT THE AREA WILL ARRIVE
ON MONDAY NIGHT. FORCING MECHANISM IS REALLY MORE ACCURATELY
DESCRIBED AS JUST A THIN RIBBON OF CYCLONIC SHEAR VORTICITY ON THE
UPWIND SIDE OF DEEPENING EAST COAST TROUGH. AS SUCH...FORCING FOR
ASCENT IS PRETTY MINUSCULE AND RESIDENT AIRMASS...AT LEAST IN THE
MIDLEVELS...IS VERY DRY. WEAK 285K ISENTROPIC ASCENT AND SUBTLE LOW
LEVEL MOISTURE ADVECTION MAY GENERATE SOME VERY LIGHT SNOW BUT
LITTLE TO NO ACCUMULATION IS EXPECTED. PREFERENCE STILL LIES WITH
THE DRIER/FURTHER SOUTHWEST CANADIAN AND EUROPEAN SOLUTIONS.
ACTUALLY AM A LITTLE CONCERNED ABOUT POTENTIAL FOR FREEZING DRIZZLE.
NAM AND GFS FORECAST SOUNDINGS INDICATE DEEP ENOUGH SATURATION TO
SUPPORT ICE NUCLEATION BUT JUST BARELY AND AM CONCERNED THEY ARE
OVERDOING THE EXTENT OF LOW LEVEL MOISTURE AND ASCENT. WILL HOLD OFF
ON INCLUDING IN THE FORECAST FOR NOW GIVEN THE HIGHER PROBABILITY
THAT ANY PRECIPITATION THAT DOES MANAGE TO OCCUR WILL DO SO IN AN
ENVIRONMENT ADEQUATELY SATURATED TO SUPPORT ICE NUCLEI AND OTHER
LOCATIONS WILL SIMPLY REMAIN DRY. SOMETHING TO KEEP AN EYE ON THOUGH.
MORE IMPRESSIVE WAVE IS SET TO PLOW OVER THE WEST COAST RIDGE ON
WEDNESDAY. THIS ACTUALLY FORCES DOWNSTREAM HEIGHT RISES LOCALLY WITH
A BRIEF RETURN TO SOUTHWEST FLOW AND WARMER TEMPERATURES. SHORTWAVE
WILL THEN ENTER OUR REGION ON THURSDAY WITH THE NEXT DECENT CHANCE
OF PRECIP. NEEDLESS TO SAY....FORECAST CONFIDENCE IN EXACT TRACK IS
LOW AND THIS WILL HAVE A LARGE IMPACT ON THERMAL PROFILES AND QPF
TOTALS. CURRENTLY APPEARS THE BEST CHANCE FOR SIGNIFICANT SNOW WILL
REMAIN OVER CENTRAL MICHIGAN WITH MORE OF A MIX ACROSS NORTHERN
INDIANA AND OHIO. THIS WILL UNDOUBTEDLY CHANGE AS WE GET CLOSER
THOUGH.
AFTER A COLD START ON MONDAY...TEMPERATURES WILL QUICKLY RETURN TO
VALUES AT OR ABOVE NORMAL FOR THE MIDWEEK PERIOD. COOLER TEMPS
EXPECTED AFTER THURSDAY`S WAVE BUT MUCH COLDER CONDITIONS STILL
APPEAR POSSIBLE EARLY NEXT WEEK AFTER A THIRD WAVE/ARCTIC FRONT
PASSES OVER THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1236 AM EST SUN JAN 25 2015
MVFR CIGS WERE ACROSS THE TAF SITES AT ISSUANCE BUT CONDITIONS
WERE HIGHLY VARIABLE WITH MUCH OF WEST CENTRAL AND NORTHWEST
INDIANA BEING VFR. AN AREA OF LOCAL VIS BELOW 1SM BR WAS
DEVELOPING AROUND KVPZ. HIRES GUIDANCE ACTUALLY CAPTURES THIS
SMALL AREA AND EXPANDS IT EAST TOWARD KSBN OVERNIGHT. WILL HAVE TO
MONITOR BUT DID INTRODUCE MVFR VIS TO KSBN. CLIPPER SYSTEM TO
DIVE EVEN FURTHER SOUTH NOW WITH SFC LOW MOVING OVER KEVV TODAY.
HEAVIER SNOWFALL WILL BE SOUTH OF TERMINALS BUT STILL EXPECT TO
SEE LIGHT SNOW FROM LATE MORNING TO EARLY EVENING WITH IFR AT KSBN
AND LIFR STILL POSSIBLE AT KFWA.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
757 PM CST MON JAN 26 2015
.UPDATE...
ISSUED AT 754 PM CST MON JAN 26 2015
RADAR/OBS AND REPORTS SUGGEST FREEZING DRIZZLE OVER NW IL CWA HAS
LARGELY DIMINISHED TO VERY SPOTTY ATTIM. ANTICIPATE A RENEWED
ROUND OF VERY LIGHT PCPN DEVELOPING SOUTHWARD FROM WI... AND
AFFECTING FAR NORTHEAST/EAST CENTRAL IA AND NORTHWEST IL OVER THE
NEXT FEW HOURS AS VORT MAX DROP SEWD FROM WI. BEING IN AND OUT
OF ICE IN CLOUDS LOOKS LIKE PCPN WILL BE FLURRIES/LIGHT SNOW WITH
ALSO SOME FREEZING DRIZZLE. HAVE ADDED LOW CHANCE POPS NORTHWEST IL
FOR VERY MINOR MEASURABLE PCPN POTENTIAL.
&&
.SYNOPSIS...
ISSUED AT 305 PM CST MON JAN 26 2015
STRONG WARM FRONT EXTENDED FROM EXTREME WESTERN WI TO NEAR OTTUMWA
IA AND THEN INTO NORTH TX. AHEAD OF THE FRONT TEMPERATURES WERE IN
THE 20S WHILE TO THE WEST READINGS HAVE SOARED INTO THE 50S IN
CENTRAL/WESTERN IA AND MO AND IN THE 60S AND LOWER 70S IN THE GREAT
PLAINS.
DOPPLER RADAR/SURFACE OBS WERE INDICATING THE SNOW HAS SHIFTED
INTO SE WI/NE IL WITH AN AREA OF FREEZING DRIZZLE IN SW WI.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 305 PM CST MON JAN 26 2015
FORECAST FOCUS ON SOME FREEZING DRIZZLE EARLY THIS EVENING
OTHERWISE MILDER TEMPERATURES.
TONIGHT...AREAS OF LIGHT FREEZING DRIZZLE IN NW IL SHOULD END
EARLY THIS EVENING BUT CLOUDS SHOULD LINGER ACROSS MUCH OF THE CWA
DURING THE NIGHT. OUR FAR WESTERN COUNTIES WILL BE PARTLY TO
MOSTLY CLOUDY. FORECAST SOUNDINGS INDICATE A STRENGTHENING
INVERSION AT 900 MB WHICH SHOULD TRAP THE LOW LEVEL MOISTURE BELOW.
THE WARM FRONT WILL CONTINUE TO PUSH WEST TO EAST ACROSS THE CWA
WHICH WILL BRING A WARMER NIGHT...COMPARED TO LAST NIGHT. MINIMUM
TEMPERATURES SHOULD RANGE FROM THE MID 20S IN NW IL TO AROUND 30
IN OUR FAR SOUTHERN CWA.
TUESDAY...INVERSION AND NORTHEAST WINDS SHOULD KEEP CLOUDS LINGERING
INTO THE MORNING WITH DECREASING CLOUDS IN THE AFTERNOON. HOWEVER...
SOME OF THE GUIDANCE KEEPS SKIES CLOUDY ALL DAY SO THIS WILL BE
CHALLENGING. I WILL FORECAST MAXIMUM TEMPERATURES IN THE LOWER 30S
NE TO THE LOWER 40S SW.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 305 PM CST MON JAN 26 2015
TWO MAIN FORECAST CONCERNS FOR THE EXTENDED FORECAST. THE FIRST IS
A WEATHER PRODUCER THAT BRUSHES THE AREA WEDNESDAY NIGHT AND
THURSDAY AND ANOTHER LOW THAT MOVES THROUGH THE REGION THIS
WEEKEND. THE FIRST EVENT LOOKS TO A RAIN/FZDZ EVENT ACROSS THE AREA
AND THE OTHER A SNOW EVENT THIS WEEKEND.
AFTER A MILD WEEK LAST WEEK AND SNOW THIS PAST WEEKEND...WE HAVE
ANOTHER TASTE OF MILD WEATHER THROUGH WEDNESDAY NIGHT AND THEN
WINTER WEATHER LOOKS TO RETURN TO THE AREA.
WEDNESDAY NIGHT INTO THURSDAY...TWO SHORTWAVE IN RAPID SUCCESSION
WILL MOVE THROUGH THE AREA. THE FIRST ONE WILL MOVE THROUGH SOUTH OF
OUR CWA ON WEDNESDAY PM INTO THURSDAY AM. THIS WILL HELP TO
CONTINUE H85 WAA THROUGH 06Z ON THURSDAY. WITH WARM AIR IN PLACE
ACROSS THE AREA THE DOMINANT PRECIP TYPE WILL BE RA EARLY ON
WEDNESDAY NIGHT. THE SECOND WAVE MOVES THROUGH BETWEEN 15Z AND 21Z
ON THURSDAY. HOWEVER BEFORE THIS ON THURSDAY AM WE SEE CAA BEGIN AND
A COOLING COLUMN...ESPECIALLY AT THE SURFACE. WITH MOST OF THE
COLUMN SATURATION OCCURRING AT TEMPS ABOVE -9C...ICE WILL NOT BE
ACTIVE...SO SNOW LOOKS UNLIKELY. INSTEAD MODEL SOUNDINGS SUGGEST
THAT FZDZ WILL OCCUR...ESPECIALLY ACROSS NORTH ZONES. WITH LOW QPF
AND POPS ONLY A GLACE...0.01 INCHES OF ICE IS FORECAST. THIS COULD
BE ENOUGH TO ICE UP ROADS...ACROSS THAT AREA. THE INITIAL SURGE OF
COLD AIR IS TEMPERED ENOUGH THAT TEMPS WILL RISE DIURNALLY TO ABOVE
FREEZING CWA WIDE...MEANING THAT THE GLAZE OF ICE SHOULD MELT BY
LATER IN THE AFTERNOON. 12Z GUIDANCE DID PULL THIS SYSTEM FURTHER
NORTH AND EAST...SO THERE IS A POTENTIAL FOR THIS EVENT TO BE
REFINED FURTHER IN FUTURE EVENTS.
A PERIOD OF NW FLOW THEN DOMINANTS THROUGH THE END OF THE WEEK AND
INTO SATURDAY WHERE TEMPS STAY NEAR FREEZING FOR HIGHS.
A TROUGH AND DEVELOPING SURFACE LOW DEVELOPS AND MOVES INTO OUR AREA
FOR THE WEEKEND. THERE ARE DISCREPANCIES BETWEEN THE GFS AND EURO
AS FAR AS TIMING AND LOCATION/STRENGTH OF SURFACE FEATURES. THE GFS
BRINGS WELL DEVELOPED SURFACE LOW TO OUR NORTH..WHEREAS THE EURO AND
GEM KEEP THE LOWER PRESSURE SOUTH. REGARDLESS...TEMPS WILL BE COLD
ENOUGH FOR ALL SNOW. THE SYSTEM THIS WEEKEND BEARS WATCHING THROUGH
THE WEEK. IT IS IMPORTANT TO NOTE THAT 00Z EURO AND OTHER PREVIOUS
RUNS OF THE EURO KEPT US DRY AND HAS BEEN TRENDING TOWARDS THIS
SYSTEM...THE GFS HAS DONE THE SAME THING. SO WE WILL SEE WHAT
HAPPENS WITH THE NEXT FEW RUNS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 548 PM CST MON JAN 26 2015
WARM FRONT EXTENDS JUST WEST OF THE MISSISSIPPI RIVER TO START
THE TAF CYCLE. GENERALLY VFR CONDITIONS ON NORTHWEST WINDS
BEING FOUND WEST OF THE BOUNDARY... WHILE ALONG AND EAST OF THE
BOUNDARY MVFR TO IFR CONDITIONS PREVAIL. THE WARM FRONT IS
EXPECTED TO PUSH EAST OF THE MISSISSIPPI RIVER AND THE TAF SITES
BY LATE EVENING WITH CONDITIONS LIKELY SETTLING MAINLY INTO
MVFR AND VFR. SOME PATCHY FREEZING DRIZZLE WILL BE POSSIBLE AT
KDBQ AND KMLI UNTIL THE BOUNDARY PASSES. FORECAST OVERNIGHT INTO
TUESDAY AM IS SIDING TOWARD LATEST RAP AND HRRR CLOUD PROGS WHICH
SHOW STRATUS MIGRATING SOUTHWARD FROM MN IN NORTHERLY FLOW AND
HAVE CIGS AT ALL SITES BECOMING MAINLY MVFR IN 1500-3000FT AGL
RANGE. MAY SEE SOME PARTIAL CLEARING BY TUESDAY PM AS FLOW TURNS
EASTERLY AND USHERS IN SLIGHTLY DRIER AIR.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...05
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...GIBBS
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
558 PM CST MON JAN 26 2015
.SYNOPSIS...
ISSUED AT 305 PM CST MON JAN 26 2015
STRONG WARM FRONT EXTENDED FROM EXTREME WESTERN WI TO NEAR OTTUMWA
IA AND THEN INTO NORTH TX. AHEAD OF THE FRONT TEMPERATURES WERE IN
THE 20S WHILE TO THE WEST READINGS HAVE SOARED INTO THE 50S IN
CENTRAL/WESTERN IA AND MO AND IN THE 60S AND LOWER 70S IN THE GREAT
PLAINS.
DOPPLER RADAR/SURFACE OBS WERE INDICATING THE SNOW HAS SHIFTED
INTO SE WI/NE IL WITH AN AREA OF FREEZING DRIZZLE IN SW WI.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 305 PM CST MON JAN 26 2015
FORECAST FOCUS ON SOME FREEZING DRIZZLE EARLY THIS EVENING
OTHERWISE MILDER TEMPERATURES.
TONIGHT...AREAS OF LIGHT FREEZING DRIZZLE IN NW IL SHOULD END
EARLY THIS EVENING BUT CLOUDS SHOULD LINGER ACROSS MUCH OF THE CWA
DURING THE NIGHT. OUR FAR WESTERN COUNTIES WILL BE PARTLY TO
MOSTLY CLOUDY. FORECAST SOUNDINGS INDICATE A STRENGTHENING
INVERSION AT 900 MB WHICH SHOULD TRAP THE LOW LEVEL MOISTURE BELOW.
THE WARM FRONT WILL CONTINUE TO PUSH WEST TO EAST ACROSS THE CWA
WHICH WILL BRING A WARMER NIGHT...COMPARED TO LAST NIGHT. MINIMUM
TEMPERATURES SHOULD RANGE FROM THE MID 20S IN NW IL TO AROUND 30
IN OUR FAR SOUTHERN CWA.
TUESDAY...INVERSION AND NORTHEAST WINDS SHOULD KEEP CLOUDS LINGERING
INTO THE MORNING WITH DECREASING CLOUDS IN THE AFTERNOON. HOWEVER...
SOME OF THE GUIDANCE KEEPS SKIES CLOUDY ALL DAY SO THIS WILL BE
CHALLENGING. I WILL FORECAST MAXIMUM TEMPERATURES IN THE LOWER 30S
NE TO THE LOWER 40S SW.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 305 PM CST MON JAN 26 2015
TWO MAIN FORECAST CONCERNS FOR THE EXTENDED FORECAST. THE FIRST IS
A WEATHER PRODUCER THAT BRUSHES THE AREA WEDNESDAY NIGHT AND
THURSDAY AND ANOTHER LOW THAT MOVES THROUGH THE REGION THIS
WEEKEND. THE FIRST EVENT LOOKS TO A RAIN/FZDZ EVENT ACROSS THE AREA
AND THE OTHER A SNOW EVENT THIS WEEKEND.
AFTER A MILD WEEK LAST WEEK AND SNOW THIS PAST WEEKEND...WE HAVE
ANOTHER TASTE OF MILD WEATHER THROUGH WEDNESDAY NIGHT AND THEN
WINTER WEATHER LOOKS TO RETURN TO THE AREA.
WEDNESDAY NIGHT INTO THURSDAY...TWO SHORTWAVE IN RAPID SUCCESSION
WILL MOVE THROUGH THE AREA. THE FIRST ONE WILL MOVE THROUGH SOUTH OF
OUR CWA ON WEDNESDAY PM INTO THURSDAY AM. THIS WILL HELP TO
CONTINUE H85 WAA THROUGH 06Z ON THURSDAY. WITH WARM AIR IN PLACE
ACROSS THE AREA THE DOMINANT PRECIP TYPE WILL BE RA EARLY ON
WEDNESDAY NIGHT. THE SECOND WAVE MOVES THROUGH BETWEEN 15Z AND 21Z
ON THURSDAY. HOWEVER BEFORE THIS ON THURSDAY AM WE SEE CAA BEGIN AND
A COOLING COLUMN...ESPECIALLY AT THE SURFACE. WITH MOST OF THE
COLUMN SATURATION OCCURRING AT TEMPS ABOVE -9C...ICE WILL NOT BE
ACTIVE...SO SNOW LOOKS UNLIKELY. INSTEAD MODEL SOUNDINGS SUGGEST
THAT FZDZ WILL OCCUR...ESPECIALLY ACROSS NORTH ZONES. WITH LOW QPF
AND POPS ONLY A GLACE...0.01 INCHES OF ICE IS FORECAST. THIS COULD
BE ENOUGH TO ICE UP ROADS...ACROSS THAT AREA. THE INITIAL SURGE OF
COLD AIR IS TEMPERED ENOUGH THAT TEMPS WILL RISE DIURNALLY TO ABOVE
FREEZING CWA WIDE...MEANING THAT THE GLAZE OF ICE SHOULD MELT BY
LATER IN THE AFTERNOON. 12Z GUIDANCE DID PULL THIS SYSTEM FURTHER
NORTH AND EAST...SO THERE IS A POTENTIAL FOR THIS EVENT TO BE
REFINED FURTHER IN FUTURE EVENTS.
A PERIOD OF NW FLOW THEN DOMINANTS THROUGH THE END OF THE WEEK AND
INTO SATURDAY WHERE TEMPS STAY NEAR FREEZING FOR HIGHS.
A TROUGH AND DEVELOPING SURFACE LOW DEVELOPS AND MOVES INTO OUR AREA
FOR THE WEEKEND. THERE ARE DISCREPANCIES BETWEEN THE GFS AND EURO
AS FAR AS TIMING AND LOCATION/STRENGTH OF SURFACE FEATURES. THE GFS
BRINGS WELL DEVELOPED SURFACE LOW TO OUR NORTH..WHEREAS THE EURO AND
GEM KEEP THE LOWER PRESSURE SOUTH. REGARDLESS...TEMPS WILL BE COLD
ENOUGH FOR ALL SNOW. THE SYSTEM THIS WEEKEND BEARS WATCHING THROUGH
THE WEEK. IT IS IMPORTANT TO NOTE THAT 00Z EURO AND OTHER PREVIOUS
RUNS OF THE EURO KEPT US DRY AND HAS BEEN TRENDING TOWARDS THIS
SYSTEM...THE GFS HAS DONE THE SAME THING. SO WE WILL SEE WHAT
HAPPENS WITH THE NEXT FEW RUNS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 548 PM CST MON JAN 26 2015
WARM FRONT EXTENDS JUST WEST OF THE MISSISSIPPI RIVER TO START
THE TAF CYCLE. GENERALLY VFR CONDITIONS ON NORTHWEST WINDS
BEING FOUND WEST OF THE BOUNDARY... WHILE ALONG AND EAST OF THE
BOUNDARY MVFR TO IFR CONDITIONS PREVAIL. THE WARM FRONT IS
EXPECTED TO PUSH EAST OF THE MISSISSIPPI RIVER AND THE TAF SITES
BY LATE EVENING WITH CONDITIONS LIKELY SETTLING MAINLY INTO
MVFR AND VFR. SOME PATCHY FREEZING DRIZZLE WILL BE POSSIBLE AT
KDBQ AND KMLI UNTIL THE BOUNDARY PASSES. FORECAST OVERNIGHT INTO
TUESDAY AM IS SIDING TOWARD LATEST RAP AND HRRR CLOUD PROGS WHICH
SHOW STRATUS MIGRATING SOUTHWARD FROM MN IN NORTHERLY FLOW AND
HAVE CIGS AT ALL SITES BECOMING MAINLY MVFR IN 1500-3000FT AGL
RANGE. MAY SEE SOME PARTIAL CLEARING BY TUESDAY PM AS FLOW TURNS
EASTERLY AND USHERS IN SLIGHTLY DRIER AIR.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...GIBBS
AVIATION...05
AREA FORECAST DISCUSSION
NWS DES MOINES IA
539 PM CST MON JAN 26 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 341 PM CST MON JAN 26 2015
HIGH PRESSURE RIDGE WILL SHIFT SLOWLY EAST OVERNIGHT AND BE OVER
CENTRAL MINNESOTA AND INTO NW IOWA BY MORNING. OVERNIGHT WINDS WILL
BE OUT OF THE NORTHWEST TO NORTH MUCH OF THE NIGHT. THIS FLOW WILL
EXTEND UP TO NEAR 3-4 KFT AND WILL BE THE STEERING FLOW FOR A BAND
OF STRATUS CLOUDS TO THE NORTH OVER MINNESOTA. THE STRATUS WILL DROP
SOUTH INTO NORTHERN AND CENTRAL IOWA OVERNIGHT AND COMBINED WITH
WINDS 5 TO 8 MPH WILL KEEP TEMPERATURES IN UP OVERNIGHT. CURRENT
DEWPOINTS ARE HIGH AND WELL INTO THE 30S. AS TEMPERATURES
COOL...SOME QUESTION TO THE POTENTIAL FOR FOG FORMATION. STILL WITH
CLOUDS MOVING IN FROM THE NORTH AND PERSISTENT NORTHERLY WINDS...FOG
FORMATION SHOULD BE LIMITED. BEST POTENTIAL WILL BE OVER THE FAR
WEST AS WINDS DIMINISH AS THE RIDGE NEARS FROM THE WEST. DEWPOINTS
ARE EXPECTED TO LOWER OVERNIGHT AS SFC WINDS BECOME MORE NORTHERLY
WITH DEW POINT DEPRESSIONS INCREASING WHICH WILL LIMIT FOG POTENTIAL
AS WELL. LIKELY THE BIGGER HAZARD OVERNIGHT WILL BE FROST FORMATION
ON ROADS WHERE DEWPOINTS REMAIN HIGHER THAN GROUND TEMPERATURES.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 341 PM CST MON JAN 26 2015
MODEL RESOLUTION IN THE FURTHER OUT PERIODS (SATURDAY THROUGH
MONDAY) OF THE LONG TERM FORECAST ARE COMING INTO A LITTLE BETTER
AGREEMENT TODAY...ALTHOUGH TIMING ISSUES REMAIN. THE GFS IS
STARTING TO LOOK MORE LIKE THE EURO AND CANADIAN MODELS NOW WITH
DEVELOP A TROUGH OVER THE REGION INSTEAD OF A HUGE RIDGE. THAT
MEANS TEMPS WILL BE TRENDING COLDER OVER THE WEEKEND. BY SUNDAY
MODELS ARE SUGGESTING HIGHS ABOUT 8 TO 10 DEGREES BELOW SEASONAL
NORMALS. THERE IS A CHANCE FOR SNOW SATURDAY/SATURDAY NIGHT WITH
THE PASSAGE OF A COLD FRONT BUT AGAIN TIMING ISSUES REMAIN WITH THE
CANADIAN MUCH FASTER AND THE GFS MUCH WETTER. ALONG WITH THE COLD
AND SNOW POTENTIAL...SATURDAY NIGHT AND SUNDAY LOOK BREEZY AS WELL.
WINTER RETURNS NEXT WEEKEND.
GOING BACK TO TOMORROW (TUESDAY) SOUNDINGS SHOW A WARM NOSE OFF THE
SURFACE WHICH IS MORE PRONOUNCED ACROSS THE SOUTH BUT WINDS WILL BE
NORTHERLY AND WIND SPEEDS IN THE LOWEST GATES ARE QUITE LIGHT. AS A
SURFACE LOW MOVES FROM THE PLAINS INTO THE UPPER MIDWEST...SURFACE
WINDS WILL SHIFT AROUND TO THE SOUTHEAST BUT STILL REMAIN LIGHT SO
IT DOES NOT APPEAR THAT THERE WILL BE MUCH MIXING. COUNTERING THAT
WILL BE A LOT OF SUN SO WHILE WE WILL NOT BE AS WARM AS
TODAY...TEMPS SHOULD STILL REACH THE MID 30S NORTHEAST TO LOWER 50S
SOUTHWEST.
DEEPER MIXING AND A LITTLE STRONGER FLOW WILL OCCUR TUESDAY NIGHT
AND WEDNESDAY AND THIS WILL BE OUR WARMEST PERIOD. EXPECTED CLOUD
COVER AHEAD OF AN APPROACHING STILL MAKES ME A LITTLE CAUTIOUS TO
BOOST TEMPS TOO MUCH ON WEDNESDAY...ESPECIALLY SINCE THE SURFACE LOW
SHIFTS INTO THE AREA DURING THE AFTERNOON AND WINDS DIMINISH/SHIFT
BY LATE IN THE DAY BUT I AM COMFORTABLE WITH CURRENT FORECASTS SINCE
THE WARM ADVECTION WILL BE STRONG. EXCEPT FOR THE CANADIAN...ALL
MODELS ARE SIMILAR IN THE TIMING OF THE SHORTWAVE BUT IF THE
SHORTWAVE IS SLOWER OR CLOUD COVER IS NOT EXTENSIVE THEN WE WILL BE
TOO COOL FOR WEDNESDAY. STILL GOING DRY WEDNESDAY WITH JUST SOME
INCREASING CLOUDS THROUGH THE DAY WHICH COULD HAMPER HIGHS.
WHILE MOISTURE WITH THE WEDNESDAY SYSTEM IS WOEFULLY LACKING...IT
SHOULD IMPROVE WEDNESDAY NIGHT...AT LEAST IN THE LOW LEVELS. PRECIP
WILL BE POSSIBLE ALONG AND WITH THE PASSAGE OF A COLD FRONT AND A
SECOND SHORT WAVE WEDNESDAY NIGHT BUT THERE IS NO ICE INTRODUCTION
AND FRANKLY ABOVE 850MB THERE ISN`T MUCH MOISTURE AT ALL AND
NEGLIGIBLE FORCING. ALL THAT I SEE WEDNESDAY NIGHT INTO THURSDAY
MORNING IS A TRANSITION FROM MAY SOME RAIN OR MORE LIKELY DRIZZLE TO
FREEZING DRIZZLE OVERNIGHT INTO EARLY THURSDAY MORNING. THE
REMAINDER OF THURSDAY INTO FRIDAY WILL BE COLD BUT DRY WITH COLD
AIR CONTINUING TO FUNNEL INTO THE REGION THROUGH THE WEEKEND.
&&
.AVIATION...27/00Z
ISSUED AT 537 PM CST MON JAN 26 2015
PRIMARY CONCERN THROUGH THE PERIOD WILL BE PROGRESSION OF MVFR/VFR
STRATUS THAT EXTENDS ALONG AND NE OF KEST-KAMW-KOOA LINE AT
23Z...ALL THE WAY BACK INTO MN...WI AND IL IN BROAD CYCLONIC FLOW.
ALL MODELS SEEM TO SLIDE THE STRATUS SLOWLY SOUTH AND WEST INTO
THE EVENING. RAP AND ARW CORE HIGH RES MODELS SEEM TO BE DOING
BETTER THAN NAM AND NMM CORES WHICH MAY STILL BE INFLUENCED BY
OVERZEALOUS MODEL SNOW COVER INITIALIZATION. THERE IS HIGH
CONFIDENCE THAT AT LEAST PATCHY MVFR CIGS WILL OOZE SW THROUGH IA
OVERNIGHT...BUT DURATION CONFIDENCE IS LOW. HAVE TRIED TO
EXTRAPOLATE ONSET BASED ON CURRENT TRENDS...BUT JUST LEFT ENDING
TIME AT 15Z UNTIL EXIT TRENDS BECOME MORE CLEAR.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...DONAVON
LONG TERM...FAB
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1113 AM CST SUN JAN 25 2015
...UPDATE TO AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CST SUN JAN 25 2015
A 500 MILLIBAR SHORTWAVE TROUGH WAS MOVING SOUTHEAST OVER THE
CENTRAL PLAINS EARLY THIS MORNING. AT THE SURFACE, AN ASSOCIATED LOW
PRESSURE SYSTEM WAS ALSO TRACKING SOUTHEAST OVER SOUTHERN IOWA. THE
UPPER WAVE WAS MOVING INTO OKLAHOMA EARLY THIS MORNING AS LIGHT
PRECIPITATION THAT WAS OVER THE AREA EARLIER IN THE NIGHT HAD MOVED
INTO EASTERN OKLAHOMA AND CLOUDS WERE DIMINISHING OVER WESTERN
KANSAS.
FAIRLY STRONG WINDS ALOFT WERE ALSO MOVING SOUTHEAST OVER THE AREA
IN THE WAKE OF THE SHORTWAVE. THE KDDC VWP WAS SHOWING 50-55 KNOT
WINDS OFF THE SURFACE WHICH IS IN GOOD AGREEMENT WITH 850 MILLIBAR
WIND PROGS FROM THE RUC13 AND HRRR. THESE MODELS SHOW A BROAD AREA
OF 50-60 KNOT WINDS OVER SOUTHWEST KANSAS EARLY THIS MORNING WHICH
MAKES SENSE GIVEN THE NUMEROUS REPORTS OF 25-30 KNOT WINDS REPORTS
FROM AREA AWOS`S. THE MODELS SHOW THE AREA OF STRONGER WINDS GRADUALLY
PROPAGATING SOUTHWARD INTO OKLAHOMA BY MID/LATE MORNING. WE SHOULD
SEE THE STRONG WINDS CONTINUING THROUGH MUCH OF THE DAY. THERE COULD
BE A SMALL WINDOW OF OPPORTUNITY FOR 50+ KNOT WIND GUSTS AROUND
MEDICINE LODGE LATER THIS MORNING BUT THE STRONGEST WINDS SHOULD
BE SOUTH OF SOUTHWEST KANSAS BY THE TIME THE BOUNDARY LAYER BEGINS
TO MIX OUT. WINDS IN THE LOWER ATMOSPHERE WILL GRADUALLY WEAKEN DURING
THE AFTERNOON HOURS. WE SHOULD SEE WINDS DROP OFF FAIRLY QUICKLY TOWARD
SUNSET AS THE BOUNDARY LAYER DECOUPLES.
THE MODELS ARE SHOWING A COOLER DAY FOR SOUTHWEST KANSAS THAN WAS
PREVIOUSLY THOUGHT. 850 MILLIBAR TEMPERATURES THIS AFTERNOON WILL BE
COOLER THAN SATURDAY BY SOME 4-8 DEGREES CELSIUS. THIS WILL TRANSLATE
TO HIGHS RANGING FROM AROUND 50 AT HAYS TO THE MID/UPPER 50S FROM
DODGE CITY WEST TO THE COLORADO LINE. SURFACE WINDS TONIGHT WILL
GRADUALLY SWITCH TO THE WEST AND COULD INCREASE AGAIN TO AROUND
10-12 KNOTS. THIS COULD KEEP LOW TEMPERATURES HELD UP IN THE LOWER
TO MIDDLE 30S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CST SUN JAN 25 2015
UPPER LEVEL RIDGING WILL PERSIST OVER THE ROCKIES MONDAY AND
TUESDAY BEFORE A SHORTWAVE TROUGH FLATTENS OUT THE RIDGE ON
WEDNESDAY AND PROGRESSES ACROSS THE PLAINS. THIS ENTIRE PERIOD
WILL BE CHARACTERIZED BY WARM TEMPERATURES WITH VARYING WIND
DIRECTIONS FROM DAY TO DAY IN RESPONSE TO SUBTLE CHANGES IN THE
SURFACE PRESSURE FIELD. HIGHS OUGHT TO REACH INTO THE UPPER 60S TO
LOWER 70S. A COLD FRONT WILL PASS ACROSS WESTERN KANSAS WEDNESDAY
AFTERNOON IN THE WAKE OF THIS SHORTWAVE TROUGH, WITH COOLER
TEMPERATURES RETURNING FOR WEDNESDAY NIGHT THROUGH THE REMAINDER
OF THE WEEK AS SURFACE HIGH PRESSURE BUILDS IN.
THERE IS A LOT OF UNCERTAINTY IN THE FORECAST AFTER FRIDAY AS THE
VARIOUS MODELS ARE EXHIBITING LOTS OF VARIABILITY WITH RESPECT TO
THE AMPLITUDE OF AN UPPER LEVEL LOW OVER BAJA. COLD AIR CONTINUES
TO BE DELIVERED INTO THE MIDWEST AND GREAT LAKES REGIONS. IF THE
SOUTHWESTERN SYSTEM PROGRESSES FAR ENOUGH EAST AND INTERACTS WITH
THE WESTERN AND SOUTHERN EDGE OF THE COLD DOME, THEN SNOW WOULD BE
POSSIBLE. THE OVERALL TREND IN THE MODELS OVER THE PAST FEW RUNS
HAS BEEN FOR A STRONGER SYSTEM OVER THE DESERT SOUTHWEST AND BAJA.
BUT IT IS VERY UNCERTAIN JUST HOW FAR NORTHEAST ANY PRECIPITATION
WOULD OCCUR AND JUST HOW COLD IT WILL BE OVER WESTERN KANSAS. FOR
NOW, THERE IS FAIRLY HIGH CONFIDENCE IN A CHANGE TO COOLER OR COLDER
TEMPERATURES FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1111 AM CST SUN JAN 25 2015
VFR CONDITIONS EXPECTED THROUGH TAF PD AS DRY ATMOSPHERE CONTINUES.
NORTHWESTERLY WINDS 22-30 KT WITH DECREASE NNW 8-12 KT BY 00Z. WINDS
WILL INCREASE WNW/NW AGAIN 10-20 KT BY MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 34 70 35 / 0 0 0 0
GCK 57 34 71 35 / 0 0 0 0
EHA 55 37 69 35 / 0 0 0 0
LBL 57 33 69 35 / 0 0 0 0
HYS 50 31 70 36 / 0 0 0 0
P28 54 31 70 37 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
552 AM CST SUN JAN 25 2015
...UPDATED FOR AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CST SUN JAN 25 2015
A 500 MILLIBAR SHORTWAVE TROUGH WAS MOVING SOUTHEAST OVER THE
CENTRAL PLAINS EARLY THIS MORNING. AT THE SURFACE, AN ASSOCIATED LOW
PRESSURE SYSTEM WAS ALSO TRACKING SOUTHEAST OVER SOUTHERN IOWA. THE
UPPER WAVE WAS MOVING INTO OKLAHOMA EARLY THIS MORNING AS LIGHT
PRECIPITATION THAT WAS OVER THE AREA EARLIER IN THE NIGHT HAD MOVED
INTO EASTERN OKLAHOMA AND CLOUDS WERE DIMINISHING OVER WESTERN
KANSAS.
FAIRLY STRONG WINDS ALOFT WERE ALSO MOVING SOUTHEAST OVER THE AREA
IN THE WAKE OF THE SHORTWAVE. THE KDDC VWP WAS SHOWING 50-55 KNOT
WINDS OFF THE SURFACE WHICH IS IN GOOD AGREEMENT WITH 850 MILLIBAR
WIND PROGS FROM THE RUC13 AND HRRR. THESE MODELS SHOW A BROAD AREA
OF 50-60 KNOT WINDS OVER SOUTHWEST KANSAS EARLY THIS MORNING WHICH
MAKES SENSE GIVEN THE NUMEROUS REPORTS OF 25-30 KNOT WINDS REPORTS
FROM AREA AWOS`S. THE MODELS SHOW THE AREA OF STRONGER WINDS GRADUALLY
PROPAGATING SOUTHWARD INTO OKLAHOMA BY MID/LATE MORNING. WE SHOULD
SEE THE STRONG WINDS CONTINUING THROUGH MUCH OF THE DAY. THERE COULD
BE A SMALL WINDOW OF OPPORTUNITY FOR 50+ KNOT WIND GUSTS AROUND
MEDICINE LODGE LATER THIS MORNING BUT THE STRONGEST WINDS SHOULD
BE SOUTH OF SOUTHWEST KANSAS BY THE TIME THE BOUNDARY LAYER BEGINS
TO MIX OUT. WINDS IN THE LOWER ATMOSPHERE WILL GRADUALLY WEAKEN DURING
THE AFTERNOON HOURS. WE SHOULD SEE WINDS DROP OFF FAIRLY QUICKLY TOWARD
SUNSET AS THE BOUNDARY LAYER DECOUPLES.
THE MODELS ARE SHOWING A COOLER DAY FOR SOUTHWEST KANSAS THAN WAS
PREVIOUSLY THOUGHT. 850 MILLIBAR TEMPERATURES THIS AFTERNOON WILL BE
COOLER THAN SATURDAY BY SOME 4-8 DEGREES CELSIUS. THIS WILL TRANSLATE
TO HIGHS RANGING FROM AROUND 50 AT HAYS TO THE MID/UPPER 50S FROM
DODGE CITY WEST TO THE COLORADO LINE. SURFACE WINDS TONIGHT WILL
GRADUALLY SWITCH TO THE WEST AND COULD INCREASE AGAIN TO AROUND
10-12 KNOTS. THIS COULD KEEP LOW TEMPERATURES HELD UP IN THE LOWER
TO MIDDLE 30S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CST SUN JAN 25 2015
UPPER LEVEL RIDGING WILL PERSIST OVER THE ROCKIES MONDAY AND
TUESDAY BEFORE A SHORTWAVE TROUGH FLATTENS OUT THE RIDGE ON
WEDNESDAY AND PROGRESSES ACROSS THE PLAINS. THIS ENTIRE PERIOD
WILL BE CHARACTERIZED BY WARM TEMPERATURES WITH VARYING WIND
DIRECTIONS FROM DAY TO DAY IN RESPONSE TO SUBTLE CHANGES IN THE
SURFACE PRESSURE FIELD. HIGHS OUGHT TO REACH INTO THE UPPER 60S TO
LOWER 70S. A COLD FRONT WILL PASS ACROSS WESTERN KANSAS WEDNESDAY
AFTERNOON IN THE WAKE OF THIS SHORTWAVE TROUGH, WITH COOLER
TEMPERATURES RETURNING FOR WEDNESDAY NIGHT THROUGH THE REMAINDER
OF THE WEEK AS SURFACE HIGH PRESSURE BUILDS IN.
THERE IS A LOT OF UNCERTAINTY IN THE FORECAST AFTER FRIDAY AS THE
VARIOUS MODELS ARE EXHIBITING LOTS OF VARIABILITY WITH RESPECT TO
THE AMPLITUDE OF AN UPPER LEVEL LOW OVER BAJA. COLD AIR CONTINUES
TO BE DELIVERED INTO THE MIDWEST AND GREAT LAKES REGIONS. IF THE
SOUTHWESTERN SYSTEM PROGRESSES FAR ENOUGH EAST AND INTERACTS WITH
THE WESTERN AND SOUTHERN EDGE OF THE COLD DOME, THEN SNOW WOULD BE
POSSIBLE. THE OVERALL TREND IN THE MODELS OVER THE PAST FEW RUNS
HAS BEEN FOR A STRONGER SYSTEM OVER THE DESERT SOUTHWEST AND BAJA.
BUT IT IS VERY UNCERTAIN JUST HOW FAR NORTHEAST ANY PRECIPITATION
WOULD OCCUR AND JUST HOW COLD IT WILL BE OVER WESTERN KANSAS. FOR
NOW, THERE IS FAIRLY HIGH CONFIDENCE IN A CHANGE TO COOLER OR COLDER
TEMPERATURES FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 548 AM CST SUN JAN 25 2015
EXPECT NORTH-NORTHWEST WINDS TO INCREASE TO 25KTS BY 17Z AND
PERSIST THROUGH 22Z AS WEAK SURFACE HIGH PRESSURE BUILDS INTO
WESTERN KANSAS. WINDS WILL DROP OFF QUICKLY BY 00Z. VFR CONDITIONS
CAN BE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 34 70 35 / 0 0 0 0
GCK 57 34 71 35 / 0 0 0 0
EHA 55 37 69 35 / 0 0 0 0
LBL 57 33 69 35 / 0 0 0 0
HYS 50 31 70 36 / 0 0 0 0
P28 54 31 70 37 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...FINCH
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
349 AM CST SUN JAN 25 2015
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CST SUN JAN 25 2015
A 500 MILLIBAR SHORTWAVE TROUGH WAS MOVING SOUTHEAST OVER THE
CENTRAL PLAINS EARLY THIS MORNING. AT THE SURFACE, AN ASSOCIATED LOW
PRESSURE SYSTEM WAS ALSO TRACKING SOUTHEAST OVER SOUTHERN IOWA. THE
UPPER WAVE WAS MOVING INTO OKLAHOMA EARLY THIS MORNING AS LIGHT
PRECIPITATION THAT WAS OVER THE AREA EARLIER IN THE NIGHT HAD MOVED
INTO EASTERN OKLAHOMA AND CLOUDS WERE DIMINISHING OVER WESTERN
KANSAS.
FAIRLY STRONG WINDS ALOFT WERE ALSO MOVING SOUTHEAST OVER THE AREA
IN THE WAKE OF THE SHORTWAVE. THE KDDC VWP WAS SHOWING 50-55 KNOT
WINDS OFF THE SURFACE WHICH IS IN GOOD AGREEMENT WITH 850 MILLIBAR
WIND PROGS FROM THE RUC13 AND HRRR. THESE MODELS SHOW A BROAD AREA
OF 50-60 KNOT WINDS OVER SOUTHWEST KANSAS EARLY THIS MORNING WHICH
MAKES SENSE GIVEN THE NUMEROUS REPORTS OF 25-30 KNOT WINDS REPORTS
FROM AREA AWOS`S. THE MODELS SHOW THE AREA OF STRONGER WINDS GRADUALLY
PROPAGATING SOUTHWARD INTO OKLAHOMA BY MID/LATE MORNING. WE SHOULD
SEE THE STRONG WINDS CONTINUING THROUGH MUCH OF THE DAY. THERE COULD
BE A SMALL WINDOW OF OPPORTUNITY FOR 50+ KNOT WIND GUSTS AROUND
MEDICINE LODGE LATER THIS MORNING BUT THE STRONGEST WINDS SHOULD
BE SOUTH OF SOUTHWEST KANSAS BY THE TIME THE BOUNDARY LAYER BEGINS
TO MIX OUT. WINDS IN THE LOWER ATMOSPHERE WILL GRADUALLY WEAKEN DURING
THE AFTERNOON HOURS. WE SHOULD SEE WINDS DROP OFF FAIRLY QUICKLY TOWARD
SUNSET AS THE BOUNDARY LAYER DECOUPLES.
THE MODELS ARE SHOWING A COOLER DAY FOR SOUTHWEST KANSAS THAN WAS
PREVIOUSLY THOUGHT. 850 MILLIBAR TEMPERATURES THIS AFTERNOON WILL BE
COOLER THAN SATURDAY BY SOME 4-8 DEGREES CELSIUS. THIS WILL TRANSLATE
TO HIGHS RANGING FROM AROUND 50 AT HAYS TO THE MID/UPPER 50S FROM
DODGE CITY WEST TO THE COLORADO LINE. SURFACE WINDS TONIGHT WILL
GRADUALLY SWITCH TO THE WEST AND COULD INCREASE AGAIN TO AROUND
10-12 KNOTS. THIS COULD KEEP LOW TEMPERATURES HELD UP IN THE LOWER
TO MIDDLE 30S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CST SUN JAN 25 2015
UPPER LEVEL RIDGING WILL PERSIST OVER THE ROCKIES MONDAY AND
TUESDAY BEFORE A SHORTWAVE TROUGH FLATTENS OUT THE RIDGE ON
WEDNESDAY AND PROGRESSES ACROSS THE PLAINS. THIS ENTIRE PERIOD
WILL BE CHARACTERIZED BY WARM TEMPERATURES WITH VARYING WIND
DIRECTIONS FROM DAY TO DAY IN RESPONSE TO SUBTLE CHANGES IN THE
SURFACE PRESSURE FIELD. HIGHS OUGHT TO REACH INTO THE UPPER 60S TO
LOWER 70S. A COLD FRONT WILL PASS ACROSS WESTERN KANSAS WEDNESDAY
AFTERNOON IN THE WAKE OF THIS SHORTWAVE TROUGH, WITH COOLER
TEMPERATURES RETURNING FOR WEDNESDAY NIGHT THROUGH THE REMAINDER
OF THE WEEK AS SURFACE HIGH PRESSURE BUILDS IN.
THERE IS A LOT OF UNCERTAINTY IN THE FORECAST AFTER FRIDAY AS THE
VARIOUS MODELS ARE EXHIBITING LOTS OF VARIABILITY WITH RESPECT TO
THE AMPLITUDE OF AN UPPER LEVEL LOW OVER BAJA. COLD AIR CONTINUES
TO BE DELIVERED INTO THE MIDWEST AND GREAT LAKES REGIONS. IF THE
SOUTHWESTERN SYSTEM PROGRESSES FAR ENOUGH EAST AND INTERACTS WITH
THE WESTERN AND SOUTHERN EDGE OF THE COLD DOME, THEN SNOW WOULD BE
POSSIBLE. THE OVERALL TREND IN THE MODELS OVER THE PAST FEW RUNS
HAS BEEN FOR A STRONGER SYSTEM OVER THE DESERT SOUTHWEST AND BAJA.
BUT IT IS VERY UNCERTAIN JUST HOW FAR NORTHEAST ANY PRECIPITATION
WOULD OCCUR AND JUST HOW COLD IT WILL BE OVER WESTERN KANSAS. FOR
NOW, THERE IS FAIRLY HIGH CONFIDENCE IN A CHANGE TO COOLER OR COLDER
TEMPERATURES FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1131 PM CST SAT JAN 24 2015
A FEW LINGERING LIGHT SHOWERS OR SPRINKLES ACROSS SOUTHWEST KANSAS
WILL QUICKLY MOVE OUT OF THE AREA DURING THE FIRST FEW HOURS OF
THIS TAF PERIOD. GUSTY NORTHWEST WINDS WILL CONTINUE ACROSS THE
AREA OVERNIGHT AND WILL INCREASE TO AROUND 25-30 KNOTS WITH GUSTS
TO 40 KNOTS AT TIME BY MID TO LATE MORNING SUNDAY. WINDS WILL
DIMINISH RAPIDLY TOWARD SUNSET ON SUNDAY
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 34 70 35 / 0 0 0 0
GCK 57 34 71 35 / 0 0 0 0
EHA 55 37 69 35 / 0 0 0 0
LBL 57 33 69 35 / 0 0 0 0
HYS 50 31 70 36 / 0 0 0 0
P28 54 31 70 37 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1127 PM CST Sat Jan 24 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Sunday)
Issued at 253 PM CST SAT JAN 24 2015
An upper level trough located across the northern plains this
afternoon will dig southeast into the mid MS river valley by Sunday
Afternoon.
The stronger ascent ahead of this upper level trough will remain
across the northern plains into the Midwest and OH river valley. The
mesoscale models show another area of stronger ascent developing
within the left exit region, ahead of an 80 KT H5 jet max, which
will dig from eastern MT this afternoon, southeast across western
KS, into northeast OK through the night. Both the Advanced Research
and Non-hydrostatic WRF model solutions show an area of light rain
developing across west central KS this evening in the region of the
left exit region of the H5 jet. ATTM, the area of light rain will
move southeast ahead of the H5 jet max and spread southeast across
south central KS into northeast OK through the night. The 12Z GFS
model is the only solution showing the area of steadier light rain
moving across the southern half of the CWA this evening. I will be
leaning more towards the ARW, NMM and HRRR solutions.
Most of the CWA will only see occasional sprinkles or very light
rain showers through the night into the morning hours of Sunday as
the H5 trough axis moves southeast. Forecast soundings continue to
show a drier layer air within the lowest 6,000 feet of the
atmosphere. Overnight lows will be mild with westerly winds of 10 to
20 MPH. Most areas should see overnight lows only dropping into the
upper 30s.
Sunday, as the upper trough amplifies across northern MO, wrap
around rain showers are possible across the northeast and east
central KS. These showers look to be light with only a trace
to 0.01 inch of QPF forecasted. A surface/925mb low will deepen
across northern MO through the day. Northwest winds will increase
through the mid morning hours to 20 to 30 MPH with gusts up to 40
MPH. The southern counties of the CWA may flirt with wind advisory
criteria during the late morning and early afternoon hours. The
low-level CAA will only allow high temperatures to reach the lower
to mid 40s across the eastern half of the CWA, where clouds may
continue through most of the day. The western counties may see some
afternoon insolation which may help highs to reach into the mid to
upper 40s.
.LONG TERM...(Sunday Night through Saturday)
Issued at 253 PM CST SAT JAN 24 2015
Sunday Night through Monday Night ...
By Sunday night, the vertically-stacked surface low and mid-level
low will be situated over the Ohio River Valley with
north-northwesterly flow aloft prevailing across the central U.S. A
narrow ridge of surface high pressure will spill southward into the
forecast area Sunday night into Monday resulting in mostly clear
skies and light winds. As a result, decent radiational cooling will
help drop overnight low temperatures into the mid/upper 20s.
Models show the next surface low positioned over the far northern U.S.
and tracking toward the Great Lakes region through Monday night. An
associated cold front will extend southward across the Northern and
Central Plains Monday morning and is expected to skim southeastward
across the forecast area from late morning through the afternoon
hours. Since this front looks to barely extend far enough south into
the area, there should not be a strong wind shift associated with
this frontal passage. As a result, models show winds gradually
veering from southwest to west-northwest through the day. Soundings
are very dry so don`t even expect much in the way of cloud cover
with this frontal passage. With a thermal ridge in place just west
of the forecast area and decent downslope winds expected, should see
another mild day with high temperatures reaching into the upper 50s
east to middle 60s west. An area of surface high pressure will
advance into the Northern and Central Plains behind the front, with
mostly clear skies and light northwesterly winds resulting in low
temperatures dropping into the low 30s by Tuesday morning.
Tuesday through Saturday Night...
A pattern of benign weather is expected Tuesday through Friday as a
dry forecast remains in place. A wave will push through the area on
Wednesday evening; however, any precipitation associated with this
energy will be to the north of the area. The next mention of
precipitation is Saturday, associated with a shortwave amplifying in
the Rocky Mountains. Two completely different solutions are seen by
the models with the ECMWF proposing energy with this system will
stay well south keeping the area completely dry, while the GFS
solution continues to amplify this wave allowing for a moderate
amount of precipitation. Due to such a robust solution with the
GFS, have put in 20 percent chances for PoPs over the entire area
Saturday, with a chance for both rain and snow. As of right now,
confidence of how this system will play out is low and should
continue to be monitored.
As for temperatures, Tuesday and Wednesday will continue to be above
normal with highs topping out in the upper 50s/lower 60s. A weak
cold front associated with the system on Wednesday will lower
temperatures slightly Thursday and Friday, with highs in the mid 40s
and lows below freezing. Saturday will be even cooler as winds
shift from the north bringing highs back to climatological normals.
&&
.AVIATION...(For the 06Z TAFs through 06Z Sunday Night)
Issued at 1124 PM CST SAT JAN 24 2015
With hit and miss light rain showers near terminals will continue
with VCSH for the first half of the forecast period. Winds pick up
gusts in the next few hours and continue through the morning into
the afternoon, before diminishing toward sunset.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Heller/Hennecke
AVIATION...67
AREA FORECAST DISCUSSION
NWS JACKSON KY
1102 PM EST MON JAN 26 2015
.UPDATE...
ISSUED AT 1100 PM EST MON JAN 26 2015
NO CRUCIAL CHANGES SINCE THE PREVIOUS UPDATE. NEAR TERM TEMPERATURES
CONTINUE TO BE WELL ON TRACK...FRESHENED THEM UP WITH THE LATEST
OBSERVATIONAL DATA...AS WELL AS THE DEW POINTS AND WINDS. FOCUS
CONTINUES TO BE THE SNOW POTENTIAL AS WE HEAD INTO THE OVERNIGHT
HOURS. HRRR HAD A GOOD HANDLE ON THE SNOW EARLIER THIS
EVENING...SHOWING AN EVENTUAL LESSENING AS WE HEADED INTO THE
CURRENT PERIOD. WHILE A FEW LIGHT SNOW SHOWERS AND/OR FLURRIES ARE
LIKELY ONGOING IN PORTIONS OF THE SW CWA...THERE IS A NOTICEABLE
BREAK IN THE WIDESPREAD PRECIP WE HAD OVER CENTRAL KY EARLIER. THAT
BEING SAID...ANOTHER BAND OF ENHANCED PRECIP IS CURRENTLY MAKING ITS
WAY FROM SOUTHERN LAKE MICHIGAN AND SOUTHWARD ACROSS INDIANA. THIS
WILL LIKELY MAKE IT INTO THE CWA OVER THE NEXT FEW HOURS.
UNFORTUNATELY...THE LATEST HRRR HAS A NOTICEABLE LACK IN
INITIALIZATION...AND FURTHERMORE IT IS SHOWING UNLIKELY ARTIFACTS AS
THIS NEXT ROUND OF PRECIP MOVES IN. NOT PUTTING MUCH FAITH INTO THE
HRRR AT THIS POINT FOR THE INCOMING PRECIP. THE LATEST NAM12 AND
ECMWF ALSO PICK UP ON THIS SECOND BAND...THOUGH THE ECMWF LIKELY HAS
THE BETTER HANDLE ON QPF TOTALS. THIS WILL BE THE THING TO MONITOR
FOR POTENTIAL UPDATES THROUGH THE NEXT FEW HOURS.
UPDATE ISSUED AT 658 PM EST MON JAN 26 2015
A BAND OF RADAR REFLECTIVITIES IS CURRENTLY MAKING ITS WAY INTO THE
SW PORTION OF THE CWA. HIGHER REFLECTIVITIES...WHICH HAVE BEEN
REPORTED TO BE PUTTING DOWN SOME QUICK SNOW IS CURRENTLY OVER CENTRAL
KY AND MAKING ITS WAY EASTWARD. WHILE MOST OF THE REFLECTIVITIES OVER
OUR CWA CURRENTLY ARE ONLY PRODUCING FLURRIES...GIVEN THE UPSTREAM
REPORTS...DID GO AHEAD AND INCREASE POPS OVER OUR SW
COUNTIES...BRINGING IN SNOW POTENTIAL A COUPLE HOURS SOONER THAN WAS
PREVIOUSLY FORECAST. ALSO ENDED UP BUMPING UP THE QPF BY A COUPLE
HUNDREDTHS IN THE SW BASED ON THE UPSTREAM REPORTS...BRINGING SNOW
TOTALS UP TO ABOUT HALF AN INCH OVERNIGHT FOR PULASKI...WAYNE...AND
MCCREARY COUNTIES. NEAR TERM TEMPERATURES SEEM TO BE IN FAIRLY GOOD
SHAPE BASED ON THE LATEST INGEST OF OBSERVATIONAL DATA.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 410 PM EST MON JAN 26 2015
AS OF MID TO LATE AFTERNOON...A SHORTWAVE TROUGH IS MOVING EAST OF
THE REGION INTO THE DEVELOPING DEEP TROUGH ACROSS THE EASTERN CONUS.
MEANWHILE THE CLIPPER SYSTEM THAT MOVED ACROSS THE AREA LAST NIGHT
INTO THIS MORNING IS BEGINNING TO REORGANIZE INTO A DEEP
NOR`EASTER/BLIZZARD EAST OF THE MID ATLANTIC STATES. THE REGION WILL
REMAIN UNDER THE INFLUENCE OF NW ALOFT BETWEEN THE DEEPENING TROUGH
ALONG THE EASTERN SEABOARD AND RIDGING EXTENDING FROM MEXICO INTO THE
ROCKIES. AT THE SFC...HIGH PRESSURE WILL ALSO GRADUALLY BUILD INTO THE
GREAT LAKES AND LOWER OH VALLEY REGION ONCE THE CLIPPER SFC LOW
APPROACHING FROM THE OH VALLEY DEPARTS ON TUESDAY.
THE SHORTWAVE TROUGH MOVING INTO WV WILL TAKE THE STEADIER SNOW WITH
IT. LOW LEVEL MOISTURE WILL REMAINS ACROSS THE AREA WITH UPSLOPE
FLOW AND SATURATION IN THE LOW CLOUDS TO COLDER THAN -8C...USUALLY
ENOUGH FOR SMALL SNOWFLAKES OF LIGHT SNOW AND FLURRIES. THE CLIPPER
SYSTEM WILL TRACK TO OUR SW FROM WESTERN KY TO THE SOUTHERN
APPALACHIANS. THIS TRACK WILL FAVOR LOCATIONS ACROSS THE SW PART OF
THE AREA FOR LIGHT SNOW OR SCATTERED SNOW SHOWER CHANCES...ALTHOUGH
MODEL TIMEHEIGHT SECTIONS FORM THE NAM AND GFS MODELS DO HAVE A
WINDOW OF RATHER DEEP MOISTURE AND RATHER WEAK OMEGA NEAR 12Z...OR 7
AM ON TUESDAY. SNOW SHOWER CHANCES WILL REMAIN NEAR THE VA BORDER ON
THE UPSLOPE FLOW INTO THIS EVENING...WITH CHANCES FOR SNOW INCREASING
ACROSS THE SOUTHWEST PART OF THE AREA THROUGH THE EVENING AND INTO
THE OVERNIGHT HOURS. DAYTIME HEATING AND COLD TEMPERATURES ALOFT WILL
LEAD TO A CONTINUED CHANCE FOR SNOW SHOWERS AND FLURRIES ON TUESDAY
AND UNTIL THE FLOW BECOMES MORE NORTHERLY LATE TUE INTO TUESDAY
EVENING. QPF WITH THIS WILL BE LIGHT WITH ANY ACCUMULATIONS OF
A HALF AN INCH OR LESS ON AVERAGE WHERE SNOW DOES OCCUR. AN SPS WAS
REISSUED TO HIGHLIGHT THE LIGHT SNOW ACCUMULATION POTENTIAL AND
REFREEZE POTENTIAL THIS EVENING AND TONIGHT.
LOWS TONIGHT WILL BE COLDEST IN THE NORTH AND EAST WHERE 850 MB TEMPS
ARE PROGGED TO BE COLDEST. WE HAVE UNDERCUT MOST GUIDANCE TEMPS ON
AVERAGE ON TUESDAY AS THERE WILL BE SNOW ON THE GROUND IN SOME AREAS
AND MODELS WERE GENERALLY TOO WARM WITH TEMPS TODAY. GRADUAL CLEARING
SHOULD OCCUR FROM LATE TUE INTO TUE NIGHT AND WITH A DRY AIRMASS
PROGGED AND SNOW COVER LIKELY REMAINING IN SOME AREAS...VALLEYS
SHOULD FALL WELL INTO THE TEENS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 356 PM EST MON JAN 26 2015
THE EXTENDED PERIOD BEGINS WITH A TROUGH EXITING TO OUR EAST AS SHORTWAVE
RIDGING BUILDS INTO EASTERN KENTUCKY. THIS RIDGING SHOULD PROVIDE A
TEMPORARY RELIEF OF PRECIP WEDNESDAY AFTERNOON INTO THURSDAY
MORNING. BY 12Z THURSDAY... BOTH GFS/ECMWF SHOW A LOW PRESSURE
SYSTEM CLIPPING NORTHERN KENTUCKY AND LIFTING NEWD FROM THE OHIO
VALLEY TOWARDS NEW ENGLAND... WITH THE GFS PROVIDING MORE SUPPORT
FOR THE MORE ROBUST ECMWF SOLUTION. ANOTHER LULL IN PRECIP FOLLOWS
UNTIL SUNDAY MORNING. AT THAT POINT... MODELS DEPICT A LARGE CLOSED
LOW IN THE SOUTHERN STREAM...OPENING UP AND SPILLING ITS ENERGY EAST
INTO THE FLOW RIDGING OVER THE TENNESSEE VALLEY. THE MODELS CONTINUE
TO SHOW SOME CONNECTION TO THE NORTHERN AND SOUTHERN STREAMS WHICH
WOULD CERTAINLY MAKE THINGS MORE INTERESTING FOR THE UPCOMING
WEEKEND IF THAT PANS OUT. FOR NOW... WILL SHOW ONLY LIMITED
INTERACTION AND EASE INTO A MORE DYNAMIC SCENARIO GIVEN THE
UNCERTAINTY AND LACK OF MODEL RUN TO RUN CONSISTENCY WITH THIS PART
OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE THE ENDING OF THE UPSLOPE SNOW
SHOWERS/FLURRIES IN THE FAR EAST EARLY WEDNESDAY MORNING WITH SOME
SUNSHINE RETURNING. THE NEXT CLIPPER SYSTEM WILL THEN MOVE INTO THE
OHIO VALLEY ON THURSDAY WITH A CHANCE FOR RAIN AND SNOW ACROSS THE
AREA FRIDAY MORNING. ONLY A BRIEF WINDOW FOR DRYING CAN BE EXPECTED
FROM FRIDAY NIGHT INTO SATURDAY NIGHT BEFORE THE POTENTIAL FOR
MAINLY SNOW ARRIVES FROM THE SOUTHWEST IN FAST LOW AND MID LEVEL
FLOW RIDING ALONG A WEST TO EAST ARCTIC BOUNDARY LYING OVER THE OHIO
VALLEY. THIS BOUNDARY IS EXPECTED TO PUSH ON THROUGH KENTUCKY BY
MONDAY MORNING WITH SNOW CHANCES CONTINUING...MAINLY IN THE
SOUTHERN PARTS OF THE CWA. THIS SYSTEM WILL HAVE TO BE CLOSELY
MONITORED AS MODELS COME INTO BETTER AGREEMENT WITH THE PHASING OF
THE NORTHERN AND SOUTHERN STREAM ENERGY AS WELL AS HOW QUICKLY THE
COLD AIR SETTLES INTO THE REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 717 PM EST MON JAN 26 2015
UPSLOPE FLOW...MIXED WITH A SHORTWAVE AND FRONTAL BOUNDARY WHICH IS
TRAVERSING THE STATE FROM EAST TO WEST OVERNIGHT...WILL RESULT IN
ANOTHER ROUND OF LIGHT SNOW ACROSS A GOOD PORTION OF SE KY
OVERNIGHT. THESE SNOW SHOWERS ARE CURRENTLY LOCATED OVER CENTRAL
KY...AND COULD BEGIN AFFECTING KSME OVER THE NEXT HOUR OR TWO...WITH
KLOZ SOON TO FOLLOW. BASED ON THE CURRENT PROJECTION OF PRECIP...THE
NORTHERN MOST TAF SITES /KSYM AND KSJS/ MAY MISS OUT ON THE SNOW ALL
TOGETHER...WITH THE EXCEPTION OF SOME PERIODS OF FLURRIES THROUGHOUT
THE NIGHT. EXPECT CIGS TO FLUCTUATE BETWEEN ALTERNATE FUEL
REQUIREMENTS AND IFR CONDITIONS AT ALL TAF SITES...WITH VIS EXPECTED
TO DROP TO THE SAME THRESHOLDS DURING ANY SNOW SHOWERS AT KSME AND
KLOZ. CONDITIONS WILL SLOWLY IMPROVE BETWEEN LATE MORNING AND EARLY
AFTERNOON TOMORROW...WITH A STRONG SURGE OF DRY AIR FALLING IN BEHIND
THE EXITING SNOW AND SHORTWAVE. VFR CONDITIONS SHOULD TAKE HOLD AT
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...JP
LONG TERM...JVM
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
113 AM EST SUN JAN 25 2015
.UPDATE...
ISSUED AT 111 AM EST SUN JAN 25 2015
IR SATELLITE SHOWING SOME MAINLY HIGH CLOUDS BEGINNING TO MOVE INTO
PORTIONS OF EASTERN KENTUCKY THIS HOUR. THERE HAVE ALSO CONTINUED TO
BE SOME SCATTERED MID LEVEL CLOUDS ACROSS THE FAR NORTH AND FAR EAST
TONIGHT. OTHERWISE WE ARE SEEING SOME PATCHY VALLEY FOG TONIGHT UNDER
MOSTLY CLEAR SKIES COMBINED WITH SNOW SEEN YESTERDAY. FRESHENED UP
GRID BASED ON LATEST OBS AND TRENDS WITH NO MAJOR UPDATES NEEDED.
UPDATE ISSUED AT 1044 PM EST SAT JAN 24 2015
MOSTLY CLEAR SKIES ARE CURRENTLY BEING SEEN ACROSS EASTERN KENTUCKY
BESIDES SOME SCATTERED HIGHER BASED STRATOCU SKIRTING BY IN THE
NORTH...AS WELL AS THE LAST OF THE LOWER CLOUDS EXITING FAR
SOUTHEASTERN KENTUCKY. THANKS TO THE CLEARING...VALLEYS HAVE DIPPED
INTO THE UPPER 20S IN SPOTS. MID AND HIGH LEVEL CLOUDS WILL BE MOVING
IN AFTER MIDNIGHT...WHICH SHOULD TEMPER THE DROP OFF...HOWEVER HAVE
LOWERED THE COOLER VALLEYS TO AROUND 27 DEGREES GIVEN THE CURRENT
TRENDS. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 711 PM EST SAT JAN 24 2015
A BATCH OF LOW CLOUDS IS CURRENTLY MOVING EAST ACROSS OUR AREA
ASSOCIATED WITH A PASSING SHORT WAVE TROUGH MOVING THROUGH THE OHIO
VALLEY. THE LATEST IR SATELLITE IMAGERY REVEALS A PRETTY DEFINED
BACK EDGE TO THESE CLOUDS...AND THE LATEST RUC DATA SUGGESTS THAT
ONCE THESE EXIT IN THE NEXT FEW HOURS...THAT ADDITIONAL LOW CLOUDS
WILL BE HARDER TO COME BY GIVEN THE WEST TO SOUTHWEST WINDS TO
REMAIN IN PLACE AND A LITTLE SUBSIDENCE TO FOLLOW THE EXITING WAVE.
MID AND HIGH LEVEL CLOUDS WILL LIKELY INCREASE ACROSS THE AREA AFTER
MIDNIGHT OUT AHEAD OF THE NEXT SYSTEM. HAVE LEFT THE LOWS AROUND THE
30 DEGREE MARK IN PLACE FOR NOW...ALTHOUGH WILL HAVE TO KEEP AN EYE
ON SHELTERED VALLEYS THAT MAY DECOUPLE AND TAKE ADVANTAGE OF SOME
EVENTUAL PARTIAL CLEARING. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 415 PM EST SAT JAN 24 2015
CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME EXTENSIVE CLOUD COVER
MOVING SOUTHEAST THROUGH THE AREA ASSOCIATED WITH A WEAK TROUGH. WITH
THIS HAS BEEN SOME LIGHT FLURRY ACTIVITY OR SPRINKLES MAINLY TAKING
AIM OVER THE NORTHEASTERN PORTION OF EASTERN KENTUCKY. WILL KEEP A
MENTION OF FLURRIES AND A POSSIBLE SNOW SHOWER OVER THE AREA AND
ESPECIALLY OVER THE EAST IN MARTIN AND PIKE COUNTY. WITH THIS
FEATURE...CLOUD COVER WILL REMAIN OVER THE AREA THROUGH THIS EVENING
AND THROUGH TONIGHT. THIS HAS KEPT TEMPERATURES SUPPRESSED THROUGH THE
DAY TODAY BUT WITH WINDS OUT OF THE SOUTHWEST REMAINING UP IN MOST
LOCATIONS TONIGHT...WILL LOOK LIKE TEMPS MAY REMAIN STEADY OR SLOWLY
FALL THROUGH THE NIGHT. HOWEVER...SOME CONCERN HERE WILL BE OVER THE
SOUTH WHERE A FEW BREAKS IN THE CLOUD COVER MAY RESULT IN TEMPS
FALLING FURTHER...ESPECIALLY IN THE VALLEYS. AS WELL...SOME CONCERN
FOR PATCHY FOG WAS A POSSIBLE OCCURRENCE TONIGHT WHERE SNOW HAD
FALLEN IN THE NORTH BUT WITH REMAINING CLOUD COVER AND WINDS
SLIGHTLY UP...WILL LIKELY NOT DEVELOP MORE THAN PATCHY INSTANCES IF
AT ALL SO LEFT THIS OUT OF THE FORECAST.
CONCERNING SUNDAY THROUGH MONDAY WITH THE APPROACHING CLIPPER
SYSTEM...MODELS HAVE TRENDED DRY WITH THIS FEATURE AND SLIGHTLY
WARMER BUT WILL STILL SEEM TO BE DEALING WITH SHOWERS FOR SUNDAY AS
THIS FRONT ARRIVES. SOUTHWEST FLOW WILL BRING TEMPERATURES UP INTO
THE 40S DURING THE DAY ON SUNDAY BEFORE THE COLDER AIR MOVES IN
SUNDAY NIGHT. DEALING WITH A CONVECTIVE PROCESS AND THE RIGHT WIND
DIRECTION FOR UPSLOPE FLOW WILL MAKE FOR THE CHANGE OVER TO SNOW BY
LATE SUNDAY NIGHT AND INTO MONDAY...ESPECIALLY IN THE HIGHER
ELEVATIONS. AS THE CASE IN THESE EVENTS...THE DEPTH OF THE MOISTURE
IN THE COLUMN DOES BEGIN TO EXIT COME MONDAY AFTERNOON DURING THE
UPSLOPE PORTION OF THIS EVENT SO SNOWFALL TOTALS WILL BE LIMITED FOR
THE LATE SUNDAY NIGHT THROUGH MONDAY PERIOD. RIGHT NOW THINKING THAT
THE VALLEYS AND THE BLUEGRASS REGION WILL BE UNDER AN INCH TOTAL WITH
MORE THAN AN INCH ABOVE 2000 FEET. WILL MENTION THIS THREAT IN THE
HWO BUT THE OCCURRENCE BEING SUNDAY NIGHT INTO MONDAY MAY REQUIRE SOME
FURTHER CONSIDERATION TO HIGHLIGHT THE IMPACT TO THE MORNING COMMUTE
ON MONDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 415 PM EST SAT JAN 24 2015
A RATHER ACTIVE PATTERN IS ANTICIPATED THROUGH THE PERIOD. MODELS
WERE IN GENERALLY IN GOOD AGREEMENT AND THE FORECAST WAS KEPT VERY
CLOSE TO THE MODEL CONSENSUS BLEND. AT THE START OF THE
PERIOD...A TROUGH IS EXPECTED TO EXTEND FROM EASTERN CANADA INTO THE
GREAT LAKES REGION AND EASTERN SEABOARD. MEANWHILE A RIDGE IS
EXPECTED TO EXTEND FROM MEXICO NORTH INTO THE ROCKIES. THIS WILL
LEAD TO NW FLOW ALOFT INITIALLY WITH A SERIES OF SHORTWAVES EXPECTED
TO DROP DOWN ACROSS THE LOWER OH VALLEY REGION AND APPALACHIANS. THE
TROUGH AXIS IS EXPECTED TO GRADUALLY MOVE OFF THE EASTERN SEABOARD
BY MIDWEEK...WITH THE RIDGE SHIFTING EAST TO THE PLAINS STATES AND
EVENTUALLY OH VALLEY REGION. HOWEVER...A SHORTWAVE MOVING AROUND THE
RIDGE AND A TROUGH IN THE NORTHERN STREAM WILL BEGIN TO INTERACT
OVER THE PLAINS AT MIDWEEK AND THE RESULTING TROUGH SHOULD DAMPEN
THE RIDGE AND APPROACH THE REGION LATE WED NIGHT. THIS SYSTEM WILL
MOVE ACROSS THE GREAT LAKES AND OH VALLEY REGION ON THU INTO
THURSDAY NIGHT. THE ASSOCIATED SFC LOW IS EXPECTED TO TRACK NORTH OF
THE OH RIVER AND THEN INTO THE NORTHEAST OR MID ATLANTIC STATES.
THIS WOULD BRING THE TRAILING COLD FRONT ACROSS EAST KY ON THU TO THU
EVENING.
FROM FRI INTO SATURDAY..THE MODEL CONSENSUS IS FOR SOME FLATTENING
OF THE FLOW AT LEAST BRIEFLY FROM THE PLAINS INTO THE EASTERN CONUS
THOUGH ANOTHER SHORTWAVE WILL BEGIN TO APPROACH THE AREA LATE IN THE
PERIOD.
THE SHORTWAVES IN NW FLOW SHOULD BRING AT LEAST PERIODS OF CLOUDS OR
PROLONG CLOUDS ACROSS THE REGION WITH THE LOW LEVEL FLOW MAINTAINING
AN UPSLOPE COMPONENT. THERE ARE SOME TIMING DIFFERENCES FOR THE MON
NIGHT TO TUE PERIOD WITH THE 12Z GFS RECENT NAM RUNS ARE ALSO MORE
MOIST THE 12Z ECMWF. SOME LIGHT SNOW OR FLURRIES AS WELL AS SNOW
SHOWERS WILL BE POSSIBLE ESPECIALLY DURING DAYTIME HEATING ON TUE
WHICH WOULD STEEPEN LAPSE RATES. ANY SNOW SHOWERS COULD PRODUCE AT
LEAST SOME LOCALIZED LIGHT AMOUNTS MON NIGHT INTO TUE NIGHT. FOR
POPS DURING THIS PERIOD...WENT A BIT HIGHER THAN THE MODEL BLEND
CLOSER TO PERSISTENCE FROM THE PREVIOUS FORECAST. GENERALLY DRY
WEATHER IS EXPECTED BRIEFLY AT MIDWEEK.
FOR LATE WED NIGHT INTO THU...AT THE ONSET OF THE PRECIPITATION
WETBULBING COULD LEAD TO A MIX WITH SNOW DEPENDING ON HOW QUICKLY IT
ARRIVES. HOWEVER...ANY PRECIPITATION WITH THIS SYSTEM SHOULD REMAIN
AS MOSTLY IF NOT ENTIRELY RAIN UNTIL THE PASSAGE OF THE COLD FRONT.
TEMPERATURES SHOULD AVERAGE BELOW NORMAL FOR TUE INTO WED...BUT THEN
MODERATE TO ABOVE NORMAL ON THU IN BETWEEN SYSTEM UNDER THE
INFLUENCE OF WEAK RIDGING. BEHIND THE SHORTWAVE AND COLD
FRONT...TEMPS SHOULD AGAIN RETURN TO BELOW NORMAL LEVELS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1232 AM EST SUN JAN 25 2015
MOST SITES ARE SEEING GENERALLY VFR CONDITIONS TONIGHT...BUT MOSTLY
CLEAR SKIES COUPLED WITH SNOW SEEN YESTERDAY IS ALLOWING FOR A SOME
PATCHY FOG MAINLY IN VALLEY LOCATIONS. THAT SAID WE ARE SEEING SOME
SITES WITH VIS RUNNING AT OR NEAR MVFR CONDITIONS TONIGHT. RIGHT NOW
WILL KEEP TAF SITES AT VFR...BUT WOULD NOT BE SURPRISED IF WE SEE
SOME BRIEF LOWERING TO MVFR VIS. SYM AND SJS HAVE SEEN SCT TO BKN MID
LEVEL CLOUD DECK STILL STREAMING ACROSS THOSE SITES THIS HOUR. MOST
OF THIS WILL CONTINUE TO MOVE SOUTH AND EAST OUT OF EASTERN KENTUCKY.
OTHERWISE MOST SITES WILL SEE INCREASING HIGH CLOUDS OVERNIGHT AHEAD
OF NEXT SHORTWAVE AND SURFACE LOW DROPPING SOUTHEAST INTO THE REGION
SUNDAY. PRECIP WILL SPREAD INTO THE REGION SUNDAY AFTERNOON WITH CIGS
CONTINUING TO LOWER AS WE MOVE INTO SUNDAY NIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...SHALLENBERGER
LONG TERM...JP
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1233 AM EST SUN JAN 25 2015
.UPDATE...
ISSUED AT 1044 PM EST SAT JAN 24 2015
MOSTLY CLEAR SKIES ARE CURRENTLY BEING SEEN ACROSS EASTERN KENTUCKY
BESIDES SOME SCATTERED HIGHER BASED STRATOCU SKIRTING BY IN THE
NORTH...AS WELL AS THE LAST OF THE LOWER CLOUDS EXITING FAR
SOUTHEASTERN KENTUCKY. THANKS TO THE CLEARING...VALLEYS HAVE DIPPED
INTO THE UPPER 20S IN SPOTS. MID AND HIGH LEVEL CLOUDS WILL BE MOVING
IN AFTER MIDNIGHT...WHICH SHOULD TEMPER THE DROP OFF...HOWEVER HAVE
LOWERED THE COOLER VALLEYS TO AROUND 27 DEGREES GIVEN THE CURRENT
TRENDS. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 711 PM EST SAT JAN 24 2015
A BATCH OF LOW CLOUDS IS CURRENTLY MOVING EAST ACROSS OUR AREA
ASSOCIATED WITH A PASSING SHORT WAVE TROUGH MOVING THROUGH THE OHIO
VALLEY. THE LATEST IR SATELLITE IMAGERY REVEALS A PRETTY DEFINED
BACK EDGE TO THESE CLOUDS...AND THE LATEST RUC DATA SUGGESTS THAT
ONCE THESE EXIT IN THE NEXT FEW HOURS...THAT ADDITIONAL LOW CLOUDS
WILL BE HARDER TO COME BY GIVEN THE WEST TO SOUTHWEST WINDS TO
REMAIN IN PLACE AND A LITTLE SUBSIDENCE TO FOLLOW THE EXITING WAVE.
MID AND HIGH LEVEL CLOUDS WILL LIKELY INCREASE ACROSS THE AREA AFTER
MIDNIGHT OUT AHEAD OF THE NEXT SYSTEM. HAVE LEFT THE LOWS AROUND THE
30 DEGREE MARK IN PLACE FOR NOW...ALTHOUGH WILL HAVE TO KEEP AN EYE
ON SHELTERED VALLEYS THAT MAY DECOUPLE AND TAKE ADVANTAGE OF SOME
EVENTUAL PARTIAL CLEARING. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 415 PM EST SAT JAN 24 2015
CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME EXTENSIVE CLOUD COVER
MOVING SOUTHEAST THROUGH THE AREA ASSOCIATED WITH A WEAK TROUGH. WITH
THIS HAS BEEN SOME LIGHT FLURRY ACTIVITY OR SPRINKLES MAINLY TAKING
AIM OVER THE NORTHEASTERN PORTION OF EASTERN KENTUCKY. WILL KEEP A
MENTION OF FLURRIES AND A POSSIBLE SNOW SHOWER OVER THE AREA AND
ESPECIALLY OVER THE EAST IN MARTIN AND PIKE COUNTY. WITH THIS
FEATURE...CLOUD COVER WILL REMAIN OVER THE AREA THROUGH THIS EVENING
AND THROUGH TONIGHT. THIS HAS KEPT TEMPERATURES SUPPRESSED THROUGH THE
DAY TODAY BUT WITH WINDS OUT OF THE SOUTHWEST REMAINING UP IN MOST
LOCATIONS TONIGHT...WILL LOOK LIKE TEMPS MAY REMAIN STEADY OR SLOWLY
FALL THROUGH THE NIGHT. HOWEVER...SOME CONCERN HERE WILL BE OVER THE
SOUTH WHERE A FEW BREAKS IN THE CLOUD COVER MAY RESULT IN TEMPS
FALLING FURTHER...ESPECIALLY IN THE VALLEYS. AS WELL...SOME CONCERN
FOR PATCHY FOG WAS A POSSIBLE OCCURRENCE TONIGHT WHERE SNOW HAD
FALLEN IN THE NORTH BUT WITH REMAINING CLOUD COVER AND WINDS
SLIGHTLY UP...WILL LIKELY NOT DEVELOP MORE THAN PATCHY INSTANCES IF
AT ALL SO LEFT THIS OUT OF THE FORECAST.
CONCERNING SUNDAY THROUGH MONDAY WITH THE APPROACHING CLIPPER
SYSTEM...MODELS HAVE TRENDED DRY WITH THIS FEATURE AND SLIGHTLY
WARMER BUT WILL STILL SEEM TO BE DEALING WITH SHOWERS FOR SUNDAY AS
THIS FRONT ARRIVES. SOUTHWEST FLOW WILL BRING TEMPERATURES UP INTO
THE 40S DURING THE DAY ON SUNDAY BEFORE THE COLDER AIR MOVES IN
SUNDAY NIGHT. DEALING WITH A CONVECTIVE PROCESS AND THE RIGHT WIND
DIRECTION FOR UPSLOPE FLOW WILL MAKE FOR THE CHANGE OVER TO SNOW BY
LATE SUNDAY NIGHT AND INTO MONDAY...ESPECIALLY IN THE HIGHER
ELEVATIONS. AS THE CASE IN THESE EVENTS...THE DEPTH OF THE MOISTURE
IN THE COLUMN DOES BEGIN TO EXIT COME MONDAY AFTERNOON DURING THE
UPSLOPE PORTION OF THIS EVENT SO SNOWFALL TOTALS WILL BE LIMITED FOR
THE LATE SUNDAY NIGHT THROUGH MONDAY PERIOD. RIGHT NOW THINKING THAT
THE VALLEYS AND THE BLUEGRASS REGION WILL BE UNDER AN INCH TOTAL WITH
MORE THAN AN INCH ABOVE 2000 FEET. WILL MENTION THIS THREAT IN THE
HWO BUT THE OCCURRENCE BEING SUNDAY NIGHT INTO MONDAY MAY REQUIRE SOME
FURTHER CONSIDERATION TO HIGHLIGHT THE IMPACT TO THE MORNING COMMUTE
ON MONDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 415 PM EST SAT JAN 24 2015
A RATHER ACTIVE PATTERN IS ANTICIPATED THROUGH THE PERIOD. MODELS
WERE IN GENERALLY IN GOOD AGREEMENT AND THE FORECAST WAS KEPT VERY
CLOSE TO THE MODEL CONSENSUS BLEND. AT THE START OF THE
PERIOD...A TROUGH IS EXPECTED TO EXTEND FROM EASTERN CANADA INTO THE
GREAT LAKES REGION AND EASTERN SEABOARD. MEANWHILE A RIDGE IS
EXPECTED TO EXTEND FROM MEXICO NORTH INTO THE ROCKIES. THIS WILL
LEAD TO NW FLOW ALOFT INITIALLY WITH A SERIES OF SHORTWAVES EXPECTED
TO DROP DOWN ACROSS THE LOWER OH VALLEY REGION AND APPALACHIANS. THE
TROUGH AXIS IS EXPECTED TO GRADUALLY MOVE OFF THE EASTERN SEABOARD
BY MIDWEEK...WITH THE RIDGE SHIFTING EAST TO THE PLAINS STATES AND
EVENTUALLY OH VALLEY REGION. HOWEVER...A SHORTWAVE MOVING AROUND THE
RIDGE AND A TROUGH IN THE NORTHERN STREAM WILL BEGIN TO INTERACT
OVER THE PLAINS AT MIDWEEK AND THE RESULTING TROUGH SHOULD DAMPEN
THE RIDGE AND APPROACH THE REGION LATE WED NIGHT. THIS SYSTEM WILL
MOVE ACROSS THE GREAT LAKES AND OH VALLEY REGION ON THU INTO
THURSDAY NIGHT. THE ASSOCIATED SFC LOW IS EXPECTED TO TRACK NORTH OF
THE OH RIVER AND THEN INTO THE NORTHEAST OR MID ATLANTIC STATES.
THIS WOULD BRING THE TRAILING COLD FRONT ACROSS EAST KY ON THU TO THU
EVENING.
FROM FRI INTO SATURDAY..THE MODEL CONSENSUS IS FOR SOME FLATTENING
OF THE FLOW AT LEAST BRIEFLY FROM THE PLAINS INTO THE EASTERN CONUS
THOUGH ANOTHER SHORTWAVE WILL BEGIN TO APPROACH THE AREA LATE IN THE
PERIOD.
THE SHORTWAVES IN NW FLOW SHOULD BRING AT LEAST PERIODS OF CLOUDS OR
PROLONG CLOUDS ACROSS THE REGION WITH THE LOW LEVEL FLOW MAINTAINING
AN UPSLOPE COMPONENT. THERE ARE SOME TIMING DIFFERENCES FOR THE MON
NIGHT TO TUE PERIOD WITH THE 12Z GFS RECENT NAM RUNS ARE ALSO MORE
MOIST THE 12Z ECMWF. SOME LIGHT SNOW OR FLURRIES AS WELL AS SNOW
SHOWERS WILL BE POSSIBLE ESPECIALLY DURING DAYTIME HEATING ON TUE
WHICH WOULD STEEPEN LAPSE RATES. ANY SNOW SHOWERS COULD PRODUCE AT
LEAST SOME LOCALIZED LIGHT AMOUNTS MON NIGHT INTO TUE NIGHT. FOR
POPS DURING THIS PERIOD...WENT A BIT HIGHER THAN THE MODEL BLEND
CLOSER TO PERSISTENCE FROM THE PREVIOUS FORECAST. GENERALLY DRY
WEATHER IS EXPECTED BRIEFLY AT MIDWEEK.
FOR LATE WED NIGHT INTO THU...AT THE ONSET OF THE PRECIPITATION
WETBULBING COULD LEAD TO A MIX WITH SNOW DEPENDING ON HOW QUICKLY IT
ARRIVES. HOWEVER...ANY PRECIPITATION WITH THIS SYSTEM SHOULD REMAIN
AS MOSTLY IF NOT ENTIRELY RAIN UNTIL THE PASSAGE OF THE COLD FRONT.
TEMPERATURES SHOULD AVERAGE BELOW NORMAL FOR TUE INTO WED...BUT THEN
MODERATE TO ABOVE NORMAL ON THU IN BETWEEN SYSTEM UNDER THE
INFLUENCE OF WEAK RIDGING. BEHIND THE SHORTWAVE AND COLD
FRONT...TEMPS SHOULD AGAIN RETURN TO BELOW NORMAL LEVELS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1232 AM EST SUN JAN 25 2015
MOST SITES ARE SEEING GENERALLY VFR CONDITIONS TONIGHT...BUT MOSTLY
CLEAR SKIES COUPLED WITH SNOW SEEN YESTERDAY IS ALLOWING FOR A SOME
PATCHY FOG MAINLY IN VALLEY LOCATIONS. THAT SAID WE ARE SEEING SOME
SITES WITH VIS RUNNING AT OR NEAR MVFR CONDITIONS TONIGHT. RIGHT NOW
WILL KEEP TAF SITES AT VFR...BUT WOULD NOT BE SURPRISED IF WE SEE
SOME BRIEF LOWERING TO MVFR VIS. SYM AND SJS HAVE SEEN SCT TO BKN MID
LEVEL CLOUD DECK STILL STREAMING ACROSS THOSE SITES THIS HOUR. MOST
OF THIS WILL CONTINUE TO MOVE SOUTH AND EAST OUT OF EASTERN KENTUCKY.
OTHERWISE MOST SITES WILL SEE INCREASING HIGH CLOUDS OVERNIGHT AHEAD
OF NEXT SHORTWAVE AND SURFACE LOW DROPPING SOUTHEAST INTO THE REGION
SUNDAY. PRECIP WILL SPREAD INTO THE REGION SUNDAY AFTERNOON WITH CIGS
CONTINUING TO LOWER AS WE MOVE INTO SUNDAY NIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...SHALLENBERGER
LONG TERM...JP
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1000 PM EST MON JAN 26 2015
.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY OVERNIGHT AS IT
TRACKS NORTH NORTHEAST OFF THE MID ATLANTIC AND NEW ENGLAND
COASTS. THE LOW WILL MOVE INTO THE CANADIAN MARITIMES ON
WEDNESDAY...AS HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC.
A COLD FRONT WILL CROSS THE AREA THURSDAY NIGHT...FOLLOWED BY HIGH
PRESSURE THROUGH SATURDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
UPDATE AS OF 10 PM EST...
NO CHANGES TO THE INHERITED WSW HEADLINES THIS EVENING...ALTHOUGH
CONFIDENCE IN SEEING MORE THAN AN INCH OF SNOW WITHIN THE ENTIRE
WSW IS LOW. LATEST OPERATIONAL 00Z NAM REMAINS LESS THAN IMPRESSED
WITH POTENTIAL SNOWFALL ACCUMULATIONS THRU TUESDAY MORNING. OUTSIDE
OF THE BATCH OF RAIN MOVING SOUTH OVER THE CHES BAY/EASTERN SHORE
ATTM...THE NAM AND LATEST HRRR ARE VOID OF ANY OTHER ORGANIZED
AREAS OF PCPN. AT LEAST WE HAVE BEGUN TO SEE SIGNS OF LIGHT SNOW
DEVELOPING ACROSS THE PIEDMONT/I-95 CORRIDOR THIS EVENING AS
COLDER AIR ALOFT...ASSOCIATED WITH THE APPROACHING UPPER
TROUGH...CONTINUES TO MOVE IN. HOWEVER...OTHER THAN COUNTING ON
THE UPPER TROUGH ITSELF TO GENERATE MEANINGFUL SNOW SHOWERS
OVERNIGHT/TUES MORNING...THE AREA WILL REMAIN TO FAR REMOVED FROM
THE DEEPENING SFC LOW OFFSHORE FOR SIGNIFICANT SNOW. HAVE CONTINUED TO
TRIM SNOW ACCUMULATION WORDING IN THE WSW`S THIS EVENING...AS A
COATING/HALF INCH OF SNOW MAY BE ABOUT THE WORST CASE SCENARIO
MOST PLACES. WILL MAINTAIN GENERALLY 2-3" ON THE LOWER MD EASTERN
SHORE CLOSEST TO THE SFC LOW...BUT A FURTHER REDUCTION IN SNOW
TOTALS MAY BE NECESSARY ON THE NEXT SHIFT. LOWS TONIGHT IN THE UPR
20S NW TO THE MID 30S SE. GRADUALLY IMPROVING CONDITIONS LATER
TUES MORNING INTO THE AFTERNOON.
PREVIOUS DISCUSSION...
MAIN FORECAST CHANGE WAS TO START TRIMMING BACK ON INHERITED
WINTER WX ADVSRYS AS THE LIKELIHOOD FOR 1-3IN OF SNOW HAS DECREASED
OVER MANY AREAS. WPC AND MUCH OF 12Z GUIDANCE SUPPORT THIS
IDEA...WITH THE BEST CHANCE FOR ADVSRY-LEVEL SNOWFALL STILL OVER
THE LWR MD ERN SHORE WHERE 2-4IN IS PSBL. DO NOT THINK NORFOLK AND
RICHMOND METRO AREAS WILL RECEIVE AOA 2IN...BUT WITH THE HEADLINE
ALREADY OUT AND THE POTENTIAL FOR UP TO AN INCH TO PSBLY CAUSE
SOME IMPACTS DURING THE MORNING COMMUTE...WILL KEEP THOSE AREAS
(AND AREAS N AND E) IN THE ADVSRY FOR NOW. ANOTHER ISSUE IS
TEMPS...WITH PARTS OF THE AREA STAYING JUST A TAD ABOVE FREEZING.
WILL UPDATE AS NEEDED THIS EVENG AND TNGT.
AS FOR PCPN...EXPECT MAINLY DRY CONDS DURING THE NEXT FEW HRS
ASIDE FM WORCESTER CNTY WHERE AN AREA OF RA HAS BEEN PERSISTENT.
BETTER CHANCE FOR RAIN ARRIVES THIS EVENG AS SFC LO PRES DEVELOPS
OFFSHORE. POPS RANGE FM 40-50% SW TO 70-80% NE. THE RA WILL
TRANSITION TO A RA/SN MIX THEN SN FM NW TO SE TNGT. TOTAL QPF WILL
BE UP TO A QUARTER INCH. LO TEMPS WILL RANGE FM THE UPR 20S FAR
NW TO MID 30S SE. PCPN WILL END FM W TO E ON TUE AS THE SFC LO
ADVANCES TOWARDS THE GULF OF ME AND NW CAA FLOW LEADS TO GUSTS TO
25-30 MPH NR THE CST AND LWR ERN SHORE. HI TEMPS ONLY IN THE MID
30S TO LWR 40S UNDER A CLOUDY-MSTLY CLOUDY SKY.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED CSTL LO PULLS TOWARDS THE CANADIAN
MARITIMES AS SFC HI PRES SLOWLY BLDS IN FM THE W. EXPECT
DECREASING CLOUDS TUE NIGHT WITH NW WINDS. LO TEMPS WILL RANGE
THRU THE 20S...WITH WIND CHILLS IN THE TEENS IN MOST LOCATIONS.
COOL TEMPS INTO WED AS WELL...WITH HIGHS ONLY RANGING FM THE MID
30S OVER THE LWR ERN SHORE TO THE UPR 30S TO LWR 40S ELSEWHERE.
DRY AGAIN FOR WED NIGHT WITH SIMILAR TEMPS AS TUE NIGHT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. ONE LOW PRESSURE SYSTEM MOVES FROM THE
MIDWEST TO THE NORTHEAST STATES SENDING A COLD FRONT THROUGH THE
AREA LATE THURSDAY NIGHT/EARLY FRIDAY MORNING. A CHC OF RAIN IS IN
THE FORECAST MAINLY FOR THURSDAY NIGHT WITH LIGHT SNOW PSBL FAR NRN
PORTIONS OF THE AREA. HIGH PRESSURE BUILDS IN FROM THE WEST FRIDAY
AND SATURDAY. ANOTHER COLD FRONT APPROACHES FROM THE NW AND THEN
MOVES ACROSS THE REGION LATE SUNDAY. EURO HAS A QUICK MOVING FRONTAL
WAVE MOVE ACROSS THE CAROLINAS LATE SUNDAY AND OUT TO SEA MONDAY.
THERE WILL BE A CHC FOR RAIN OR SNOW WITH THIS SYSTEM BUT CONFIDENCE
FOR SIGNIFICANT WINTER WEATHER IS LOW AT THIS POINT.
HIGH TEMPERATURES ARE FORECAST IN THE UPR 30S AND 40S THURSDAY
LOWERING TO MOSTLY 30S TO AROUND 40 SATURDAY THROUGH MONDAY. LOWS
ARE EXPECTED TO RANGE THROUGH THE 30S FRIDAY MORNING AND MOSTLY 20S
SATURDAY THROUGH MONDAY MORNINGS.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
AS LOW PRESSURE INTENSIFIES OFF THE MD/DE COAST...RAIN AND SNOW
ARE BEGINNING TO FALL ACROSS THE AREA. SNOWFALL WILL BE ON THE
LIGHT SIDE AT THE TAF SITES EXCEPT AT SBY WHERE A 2 TO 4 INCHES
ARE POSSIBLE BY TUESDAY MORNING.
SOLID IFR CONDS SHOULD HANG THROUGH TUE MORNING. PCPN WINDS DOWN
AND CONDITIONS BEGIN TO IMPROVE EARLY TUESDAY MORNING. NORTH WINDS
WILL PREVAIL...WITH GUSTS TO ~25KT AT TIMES TOWARD THE COAST.
WINDS TREND TOWARD THE NORTHWEST ON TUESDAY MORNING.
OUTLOOK...MAINLY DRY WEATHER IS EXPECTED THROUGH WED.
&&
.MARINE...
EXTENDED PERIOD OF SCA HEADLINES FORECAST THRU WEDS.
LOW PRESSURE HAS LOCATED JUST OFF THE NC/VA COAST THIS AFTERNOON.
THE LOW HAS INTENSIFIED SLIGHTLY...RESULTING IN AN UPTICK OF N-NE
WINDS OVER THE WATERS. BEGINNING TO SEE 20 KT GUSTS OVER THE
BAY/LOWER JAMES WITH GUSTS OF 30 TO 35 KT OVER THE NRN COASTAL
WATERS. SEAS HAVE RESPONDED...BUILDING TO 7 FT AT BUOY 44009. WINDS
WILL CONTINUE TO RAMP UP THRU LATE AFTERNOON WITH SOLID SCA
CONDITIONS (GUSTS TO 30 KT) EXPECTED ACROSS ALL WATERS TONIGHT AS
THE LOW INTENSIFIES RAPIDLY AND LIFTS AWAY FROM THE COAST. LOW LEVEL
CAA ALSO INTENSIFIES. GALE CONDITIONS WITH GUSTS UP TO 40 KT
EXPECTED ACROSS THE NRN COASTAL WATERS...CLOSEST TO THE STRONGEST
GRADIENT WINDS AND CAA. SEAS BUILD TO 7 TO 12 FT IN THE NRN WATERS
AND 5 TO 8 FT IN THE SRN WATERS TONIGHT. AS THE LOW LIFTS
AWAY...FLOW BACKS TO THE NW...KEEPING HIGH SEAS FROM REACHING THE
BEACHES. NO HIGH SURF PLANNED ATTM. LITTLE CHANGE TUES AS STRONG NW
FLOW PERSISTS BTWN LOW PRESSURE OFF THE NE COAST AND HIGH PRESSURE
OVER THE OH VALLEY. GALE CONDITIONS PERSIST OVER THE NRN COASTAL
WATERS THRU EARLY TUES EVENING...BEFORE SUBSIDING TO SOLID SCA
CONDITIONS. SEAS SUBSIDE TO 5-8 FT TUES-TUES NIGHT. HIGH PRESSURE
FINALLY BUILDS OVER THE WATERS LATE WEDS...ALLOWING WINDS TO
DIMINISH AOB 15 KT. SEAS SUBSIDE THRU WEDS EVENING. HIGH PRESSURE
REMAINS OVER THE WATERS THURS IN ADVANCE OF THE NEXT CLIPPER FRONT
SET TO CROSS THE WATERS THURS NIGHT.
&&
.TIDES/COASTAL FLOODING...
LOW PRESSURE INTENSIFIES RAPIDLY OFF THE MID-ATLANTIC COAST
OVERNIGHT AND TUESDAY. THE RESULT WILL BE A PERIOD OF STRONG NORTH
TO NORTHWEST WINDS OVER THE WATERS. TIDAL ANOMALIES ARE FORECAST
TO REACH 1.5 TO 2.0 FT IN THE LOWER BAY AND 2.0 TO 2.5 FT FOR THE
COASTAL AREAS OF THE ERN SHORE. MINOR FLOODING THRESHOLDS ARE
ANTICIPATED AT OCEAN CITY INLET...WITH A WATER LEVEL OF 4.9 FT.
GUIDANCE CONTINUES TO TREND DOWN FROM MODERATE FLOODING...WHICH
MAKES SENSE GIVEN A MORE NORTH TO NORTHWEST WIND DIRECTION. THE
COASTAL FLOOD WATCH HAS BEEN REPLACED WITH A COASTAL FLOOD
ADVISORY. WATER LEVELS ARE EXPECTED TO REMAIN BELOW MINOR FLOODING
THRESHOLDS IN THE LOWER BAY...BUT WILL REACH SLIGHTLY ABOVE
HIGHEST ASTRO TIDE. ANOTHER PERIOD OF HIGH ANOMALIES ARE EXPECTED
AGAIN TUESDAY...BEFORE ANOMALIES DROP OFF TUE NGT/WED AS THE LOW
LIFTS AWAY FROM THE REGION.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 1 PM EST TUESDAY FOR MDZ021>025.
COASTAL FLOOD ADVISORY UNTIL 3 AM EST TUESDAY FOR MDZ025.
NC...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TUESDAY FOR VAZ081-089-
090-093.
WINTER WEATHER ADVISORY UNTIL NOON EST TUESDAY FOR VAZ091-
094>098.
WINTER WEATHER ADVISORY UNTIL 1 PM EST TUESDAY FOR VAZ073>078-
084>086-099-100.
WINTER WEATHER ADVISORY UNTIL 11 AM EST TUESDAY FOR VAZ063-064-
070>072-082-083.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ630>638-
654-656-658.
GALE WARNING UNTIL 10 PM EST TUESDAY FOR ANZ650-652.
&&
$$
SYNOPSIS...JDM/MAS
NEAR TERM...JDM/MAS
SHORT TERM...MAS
LONG TERM...LSA
AVIATION...DAP/LSA
MARINE...SAM
TIDES/COASTAL FLOODING...AKQ
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
325 PM EST SUN JAN 25 2015
.SYNOPSIS...
LOW PRESSURE WILL BRING WIDESPREAD SNOW LATER TODAY THROUGH
MONDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
LATEST WV IMAGERY SHOWS MID LEVEL LOW CENTER JUST OVER WESTERN KY
NOW SHIFTING EAST AS THE ASSOCIATED JET MAX SITS RIGHT OVER OR
EAST OF THE TROUGH AXIS. THE HRRR HAS BEEN HANDLING THINGS WELL SO
FAR TODAY AND OPTED TO MAKE MINOR CHANGES TO AMOUNTS AND LOCATIONS
OF MORE INTENSE SNOW THIS EVENING BASED ON LATEST RUNS.
OVERALL...VERY LITTLE CHANGE WAS NEEDED TO THE PREVIOUS FORECAST
AS LATEST RUNS HELD GOOD CONTINUITY. TEMPERATURES IN THE LOWER
LEVELS ARE SLIGHTLY WARMER SOUTH OF INTERSTATE 70 AND
CONSEQUENTLY THE CHANGEOVER TO SNOW MAY NOT BE UNTIL WELL AFTER
MIDNIGHT...SO AMOUNTS MAY NOT BE QUITE AS HIGH ACROSS THE SOUTHERN
FRINGE OF THE FORECAST AREA. TO THE NORTH WHERE PRECIPITATION WILL
BE ALL SNOW...ACCUMULATIONS ARE STILL EXPECTED TO RANGE FROM 4-6
INCHES THROUGH MONDAY WITH THE GREATEST AMOUNTS FROM PITTSBURGH
NORTH TO INTERSTATE 80 WHERE MODELS SHOW THE BEST DYNAMICS. THE
MOST INTENSE SNOWFALL RATES AREA EXPECTED TO OCCUR FROM EARLY THIS
EVENING UNTIL SHORTLY AFTER MIDNIGHT. THE WINTER WEATHER ADVISORY
WHICH COVERS THE ENTIRE FORECAST AREA WAS LEFT UNCHANGED. SNOW
WILL CONTINUE THROUGH MUCH OF MONDAY AS MOISTURE WRAPS AROUND THE
LOW AND ASSOCIATED INVERTED TROUGH SHIFTS NORTHEAST OVER THE REGION.;
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
UNSETTLED CONDITIONS WILL CONTINUE UNTIL HIGH PRESSURE BUILDS IN
BY WEDNESDAY MORNING. UNTIL THEN...SCATTERED SNOW SHOWERS WILL
PERSIST UNDER NORTHWESTERLY FLOW ALOFT AND A SUFFICIENTLY
DEEP BOUNDARY LAYER. TEMPERATURES WILL FALL TO APPROXIMATELY 10
DEGREES BELOW CLIMO NORMALS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
WEDNESDAY AND WEDNESDAY NIGHT MAY BE THE ONLY DRY 24 HOUR PERIOD
FOR THE ENTIRE FORECAST AREA THROUGH THE SEVEN DAY FORECAST. HIGH
PRESSURE WILL MOVE ACROSS THE REGION ON WEDNESDAY...AND SHOULD
ALLOW FOR ONE PARTLY/MOSTLY SUNNY DAY.
FAST MOVING CLIPPER SYSTEM WILL BRING ANOTHER ROUND OF SNOW
THURSDAY INTO THURSDAY NIGHT WITH A WINTRY MIX POSSIBLE ALONG AND
SOUTH OF I-70. BUMPED UP POPS TO LIKELY FOR THIS SYSTEM. UPPER
LEVEL TROUGH WILL REMAIN IN PLACE INTO NEXT WEEKEND WITH WELL
BELOW NORMAL TEMPERATURES. SOME IMPORTANT TIMING DIFFERENCES FOR
NEXT WEEKEND WITH NEXT CLIPPER AND DELIVERY OF EVEN COLDER ARCTIC
AIR INTO THE UPPER OHO VALLEY. WPC PROGS LOOKS TO BE A GOOD
COMPROMISE WITH A CHANCE OF SNOW SHOWERS LATER SATURDAY THROUGH
SUNDAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
THERE ARE A MIX OF MVFR/IFR CIGS IN ADVANCE OF THE LOW PRESSURE
SYSTEM THAT WILL MOVE INTO THE REGION THIS AFTERNOON/EVENING. AS
WIDESPREAD SNOW ARRIVES...ALL SITES WILL BECOME IFR AND EVENTUALLY
LIFR. FKL/DUJ ARE THE ONLY SITES THAT MAY NOT DROP TO LIFR IF
HEAVIER SNOW REMAINS TO THE SOUTH. ALSO EXPECT ZZV/MGW TO HAVE A
MIX OF RAIN/SNOW BEFORE CHANGING TO ALL SNOW. INTERMITTENT VLIFR
IN HEAVIER SNOW BANDS IS ALSO POSSIBLE...BUT DO NOT HAVE
CONFIDENCE FOR TIMING/LOCATION TO INCLUDE IN 18Z TAFS. SNOW WILL
CONTINUE...BUT IS EXPECTED TO EASE UP IN INTENSITY...BY MONDAY
MORNING.
.OUTLOOK.../MONDAY THROUGH FRIDAY/...
RESTRICTIONS IN SNOW WILL CONTINUE MONDAY AFTERNOON INTO TUESDAY.
NEXT WIDESPREAD RESTRICTIONS THURSDAY AFTERNOON INTO FRIDAY WITH A
CLIPPER SYSTEM.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR MDZ001.
OH...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR PAZ007>009-
013>016-020>023-029-031-073>076.
WV...WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR WVZ001>004-
012-021>023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
801 PM EST MON JAN 26 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 434 PM EST MON JAN 26 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN AMPLIFIED PATTERN OVER
NAMERICA...FEATURING A RIDGE OVER THE WRN CONUS INTO SW CANADA AND A
TROF OVER THE E. RESULTING NW FLOW INTO THE GREAT LAKES IS CARRYING
SEVERAL MINOR DISTURBANCES TO THE SE...AND THIS HAS LED TO BKN PCPN
EXTENDING FROM IL/IN NNW INTO NRN ONTARIO PER REGIONAL RADAR
IMAGERY. IR IMAGERY SHOWS ONE DIMINISHING AREA OF ENHANCED CLOUDS
NOW SSE OF UPPER MI AND A SECOND AREA DROPPING SSE TOWARD LAKE
SUPERIOR. THE ENHANCED CLOUDS WITH THE APPROACHING SHORTWAVE HAVE
NOT CHANGED MUCH OVER THE LAST SEVERAL HRS...AND ENVIRONMENT CANADA
RADAR NEAR THUNDER BAY SHOWS A DECENT AREA OF ASSOCIATED SNOW
APPROACHING NW LAKE SUPERIOR. TO THE SE...AN AREA OF ENHANCED
CONVERGENCE OVER LAKE MI AT THE LEADING EDGE OF STRONGER SE WINDS
LED TO SOME SNOW SPREADING OFF LAKE MI INTO DELTA AND ALGER COUNTIES
TODAY. ON VIS SATELLITE IMAGERY...HIGH CLOUDS HAVE THINNED JUST
ENOUGH TO SEE THAT THERE IS LITTLE IN THE WAY OF LAKE EFFECT CLOUDS
REMAINING ON NRN LAKE MI NOW.
SHORTWAVE OFF TO THE NW WILL DIVE SE ACROSS UPPER MI TONIGHT. GIVEN
THE ENHANCED CLOUDS JUST NNW OF THE AREA...SNOW DEPICTED ON UPSTREAM
RADAR IMAGERY NEAR THUNDER BAY AND MODEST DEEP LAYER QVECTOR
CONVERGENCE INDICATED BY MODELS...EXPECT ANOTHER AREA OF STEADIER
-SN TO SPREAD SSE ACROSS THE WRN AND CNTRL FCST AREA THIS EVENING.
ERN EDGE OF THE FORCING WILL BE UP AGAINST A STEADY FEED OF LOW-
LEVEL DRY AIR EMANATING FROM HIGH PRES CENTERED OVER SOUTHERN
QUEBEC. THIS IS CERTAINLY EVIDENT IN NAM/GFS/RUC13 FCST SOUNDINGS
WHICH MAINTAIN A DRY WEDGE IN ROUGHLY THE 2-5KFT LAYER...AND HIGH
RES MODELS SHOW PCPN STAYING W OF ROUGHLY A KISQ/SHINGLETON LINE
WITH ONLY THE GEM GETTING PCPN CLOSE TO KERY. THUS...WILL NOT
INCLUDE ANY SNOW IN THE FCST OVER THE FAR E TONIGHT. THAT SAID...THE
ONLY POTENTIAL ISSUE WOULD BE FOR A COUPLE OF THE LES BANDS OFF NRN
LAKE HURON TO STREAK WNW INTO LUCE COUNTY FOR A TIME TONIGHT. BACK
TO THE W...HIGH RES MODELS SHOW PCPN AMOUNTS IN THE 0.03 TO 0.1 INCH
RANGE TONIGHT...FALLING ALMOST ENTIRELY BEFORE 06Z. WITH SLR
PROBABLY AROUND 17 TO 1...THIS SUGGESTS SNOW AMOUNTS OF 0.5 TO
NEARLY 2 INCHES. WITH LOW-LEVEL SE WINDS PROVIDING
UPSLOPING/MOISTENING OFF LAKE MICHIGAN...THE HIGHER SNOW AMOUNTS
SHOULD OCCUR ROUGHLY IN THE AREA S OF A LINE FROM IRON RIVER TO
NEGAUNEE TO ESCANABA. AS FOR TEMPS...BIGGEST CHALLENGE IS OVER THE
FAR E WHERE CLOUDS MAY THIN OUT ENOUGH LATE IN THE NIGHT FOR TEMPS
TO PLUMMET UNDER LIGHT/CALM WIND. FOR NOW...INDICATED MINS NEAR
ZERO IN THAT AREA.
QUIET DAY ON THE WAY FOR TUE WITH SFC HIGH PRES RIDGE OVER UPPER MI.
WHILE THE E WILL PROBABLY ENJOY A MOSTLY SUNNY DAY...LOW CLOUDS WILL
LIKELY TAKE SOME TIME TO SCATTER OUT OVER THE W AND CNTRL. EXPECT
HIGHS RANGING FROM THE LWR 20S E TO THE UPPER 20S W.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 437 PM EST MON JAN 26 2015
THERE WILL BE MINOR FLUCTUATIONS IN THE UPPER RIDGE ALONG THE
WESTERN COAST OF NORTH AMERICA...BUT IT WILL LARGELY STAY IN PLACE
THROUGH THE LONG TERM FORECAST. THIS WILL LEAD TO NORTHWESTERLY
FLOW ALOFT OVER THE UPPER GREAT LAKES REGION AND SEND A SERIES OF
SHORTWAVES THROUGH THE AREA.
THE UPPER GREAT LAKES REGION WILL BE UNDER WEAK RIDGING WITHIN THE
NORTHWESTERLY FLOW ALOFT TO START THE PERIOD...WHILE THE SURFACE
RIDGE WILL BE SLIDING EAST OF THE AREA. EXPECT THERE TO BE SOME
LINGERING LOWER CLOUDS OVER THE CENTRAL PART OF THE CWA...WHILE
THERE WILL BE HIGH CLOUDS SPREADING OVER THE WESTERN CWA AHEAD OF
THE NEXT SYSTEM. THESE CLOUDS WILL KEEP TEMPS FROM FALLING TOO MUCH
IN THAT AREA...BUT OVER THE EAST...CLEARING IN THE EVENING WILL
ALLOW TEMPERATURES TO QUICKLY FALL INTO THE LOWER SINGLE DIGITS
ABOVE ZERO. DID TREND TOWARDS THE BETTER PERFORMING GEM MODELS OVER
THE EAST IN THOSE CLEAR SKY AND RADIATIONAL COOLING SITUATIONS.
FOCUS THEN TURNS TO THE INVERTED TROUGH PUSHING EAST TOWARDS THE
AREA ON WEDNESDAY (FROM A LOW MOVING OUT OF THE NORTHERN/CENTRAL
PLAINS) AND THREE SHORTWAVES THAT WILL COME TOGETHER OVER THE GREAT
LAKES REGION THROUGH THURSDAY. THE INITIAL AREA OF PRECIPITATION
SHOULD STAY WELL TO THE NORTH OF UPPER MICHIGAN ON WEDNESDAY (TIED
TO THE DEEPER MOISTURE AND BROAD WARM AIR ADVECTION OVER NORTHERN
LAKE SUPERIOR. BUT AS A SECOND SHORTWAVE SLIDES SOUTHEAST INTO THE
AREA FROM MANITOBA ON WEDNESDAY NIGHT...EXPECT THE PRECIPITATION
SWEEP SOUTH THROUGH THE AREA WITH THE 850-700MB TROUGH. SHOULD SEE
1-3 INCHES OF SNOW MOVE ACROSS THE AREA ON WEDNESDAY NIGHT...WITH
THE HIGHEST AMOUNTS OVER THE EAST. COLDER AIR IS DELAYED BEHIND THE
SYSTEM...SO DON/T EXPECT MUCH IN THE WAY OF LAKE ENHANCEMENT...BUT
DID FACTOR IN SOME TERRAIN ENHANCEMENT FOR THURSDAY. WITH THAT LACK
OF COLD AIR...THE CLOUD THERMAL PROFILE IS ON THE EDGE FOR ICE
CRYSTALS. AT THIS POINT...THINK THERE WILL BE ENOUGH AND LEFT OUT
FREEZING DRIZZLE...BUT IT WILL BE SOMETHING TO WATCH.
THE COLD AIR FINALLY ARRIVES ON THURSDAY NIGHT AND REMAINS INTO
FRIDAY UNDER NORTH-NORTHWEST WINDS ALOFT. EXPECT LIGHT LAKE EFFECT
TO OCCUR IN THOSE SNOW BELTS...BUT WITH SUBSIDENCE FROM HIGH
PRESSURE BUILDING INTO THE UPPER MISSISSIPPI VALLEY...INVERSION
HEIGHTS WILL STRUGGLE TO RISE MUCH ABOVE 4-5KFT. THUS...THINK
ACCUMULATIONS WILL BE ON THE LOW SIDE...BUT THEY WILL BE EFFICIENT
AT REDUCING VISIBILITIES DUE TO THE CLOUD BEING ABOVE THE DGZ.
WINDS WILL BACK ON FRIDAY AFTERNOON/NIGHT AS THE HIGH SLIDES JUST
TO THE SOUTH OF THE AREA.
FORECAST BECOMES A LITTLE UNCERTAIN AS MODELS DIVERGE ON THE UPPER
LEVEL FEATURES. ALL IN ALL...LOOKS LIKE A WEAK TROUGH WILL SLIDE
ACROSS THE AREA ON SATURDAY AND USHER IN ANOTHER SURGE OF COLD AIR
(MID -20S 850MB TEMPS) INTO THE UPPER GREAT LAKES REGION. WILL
CONTINUE TO SHOW LAKE EFFECT POPS BEHIND THAT TROUGH IN THE NW WIND
SNOW BELTS FOR SATURDAY NIGHT INTO MONDAY. WITH THE AMOUNT OF COLD
AIR...EXPECT LIMITED SNOWFALL AMOUNTS BUT GOOD VISIBILITY
RESTRICTION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 740 PM EST MON JAN 26 2015
EXPECT MVFR CONDITIONS TO PREVAIL AT KIWD EARLY THIS EVENING BEFORE
LINGERING MOISTURE ALLOWS CONDITIONS TO FALL TO IFR BY LATE EVENING.
ANOTHER DISTURBANCE MOVING ACROSS THE AREA TONIGHT WILL BRING A
ROUND OF -SN TO KCMX AND KSAW DROPPING CONDITIONS TO IFR THIS
EVENING. IFR/LOW MVFR CIGS WILL LIKELY PERSIST AT KCMX AND KSAW INTO
TUE MORNING BEFORE IMPROVEMENT TO HIGHER END MVFR IS EXPECTED AT ALL
TAF SITES TUE AFTERNOON.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 434 PM EST MON JAN 26 2015
WITH WEAK LOW PRES OVER NE MN DROPPING SSE TONIGHT...STRONGER S
WINDS OF 20-30KT WILL CONTINUE OVER ERN LAKE SUEPRIOR THRU THIS
EVENING BEFORE DIMINISHING OVERNIGHT. WITH WEAKER PRES GRADIENT OVER
THE W...WINDS WILL BE UNDER 20KT. WINDS WILL THEN BE UNDER 20KT
ACROSS THE ENTIRE LAKE TUE/WED AS HIGH PRES RIDGE DRIFTS SSE FROM
THE UPPER LAKES. LOW PRES WILL THEN TRACK FROM THE MID MISSISSIPPI
VALLEY WED NIGHT TO THE LOWER LAKES THU NIGHT. BEHIND THE LOW...N TO
NW WINDS WILL INCREASE TO 20-30KT THU/THU NIGHT WITH GALES POSSIBLE
OVER THE E HALF OF THE LAKE. WINDS WILL THEN DIMINISH FRI AS HIGH
PRES PASSES ACROSS THE WRN GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
245 PM EST SUN JAN 25 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM EST SUN JAN 25 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALOFT
DOMINTING THE GREAT LKS BTWN HI AMPLITUDE RDG ALONG THE W COAST AND
A DEEP UPR TROF IN ERN NAMERICA CENTERED OVER NRN QUEBEC. SFC HI
PRES UNDER THIS NW FLOW IS BLDG SE THRU NW ONTARIO...WITH A COLD NNE
FLOW ON ITS SRN FLANK ADVECTING H85 TEMPS AS LO AS -15C OVER LK SUP
EARLY THIS MRNG. THE INFUSION OF THIS VERY COLD AIR OVER THE
RELATIVELY WARM LK SUP WATERS IS RESULTING IN SOME LK EFFECT SN
SHOWERS ACROSS MAINLY NCENTRAL UPR MI...WHERE THE LLVL FLOW IS
PRESENTING A MORE SGNFT UPSLOPE WIND COMPONENT. DESPITE FVRBL SN
GROWTH MICROPHYSICS WITH THE DGZ WITHIN MUCH OF THE CONVECTIVE
LYR...HI STABILITY/DRYNESS OF INCOMING AIRMASS PER THE 00Z YPL
RAOB...WHERE THE 00Z PWAT WAS ONLY 0.05 INCH AND THE SUBSIDENCE
INVRN WAS LOCATED NEAR H9 /MQT VWP INDICATES THE INVRN BASE HERE IS
NEAR 3K FT AGL/...AS WELL AS THE LARGER SCALE ACYC FLOW THAT IS
MINIMIZING LLVL CNVGC IS TENDING TO LIMIT THE INTENSITY OF THE LES.
OVER THE E...SKIES HAVE BEGUN TO CLEAR AT NEWBERRY WITH MINIMAL
OVERWATER TRAJECTORY AND SOME DOWNSLOPING OF THE LLVL NE FLOW OFF
ONTARIO...WHERE SFC DEWPTS EARLY THIS MRNG ARE AS LO AS -20 TO -25F
TO THE N OF LK SUP. LOOKING FARTHER UPSTREAM...A FAIRLY STRONG
SHRTWV IS MOVING THRU WRN CANADA OVER TOP THE WRN RDG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS ASSOCIATED WITH
THE COLD NE LLVL FLOW THAT WL PERSIST INTO THIS AFTN. FOCUS FOR TNGT
SHIFTS TO LO TEMPS AND SN CHCS LATE OVER THE W ASSOCIATED WITH
DISTURBANCE NOW TRACKING THRU WRN CANADA.
TODAY...SFC HI PRES CENTER IS FCST TO DRIFT SLOWLY TO THE SE OVER
FAR NE LK SUP BY 00Z MON. LLVL NE FLOW WL PERSIST THRU THIS
MRNG...BUT THEN WEAKEN AS THE HI CENTER MOVES CLOSER AND SFC RDG
AXIS EXTENDING TO THE SW MOVES OVHD BY 00Z. WITH THE -15C H85
ISOTHERM OVER CENTRAL LK SUP AND THE DGZ IN THE 1-3K FT LYR
ENCOMPASSING MUCH OF THE CONVECTIVE LYR...SOME FLUFFY LES WL PERSIST
IN THE NE SN BELTS OVER MAINLY THE NCENTRAL. DESPITE THE PRESENCE OF
THE DGZ AND SUFFICIENT CHILL OF THE AIRMASS...INVRN BASE NEAR 3K FT
AGL AND ACYC NATURE OF THE H925 FLOW WL CONTINUE TO LIMIT ADDITIONAL
SN ACCUMS TO AN INCH OR LESS. DURING THE AFTN WHEN THE WINDS/UPSLOPE
FORCING DIMINISH FURTHER AND THE SFC RDG AXIS BECOMES MORE
PRONOUNCED...THE LES SHOULD TEND TO DIMINISH EVEN FURTHER. THE ERN
CWA SHOULD BE MOSUNNY WITH DOWNSLOPE FLOW/MINIMAL OVERWATER
TRAJECTORY OF THE DRY AIRMASS. NEAR THE WI BORDER...SOME BREAKS IN
THE SC OVC ARE LIKELY BY MID/LATE AFTN WITH THE CLOSER APRCH OF THE
SFC RDG AXIS. BUT EVEN WHERE THE SUN COMES OUT...HI TEMPS WL BE HARD
PRESSED TO RISE OUT OF THE TEENS PER OBSVD HI TEMPS IN ONTARIO YDAY.
TNGT...AS THE SFC RDG AXIS SHIFTS TO THE E AND THE SHRTWV NOW OVER
WRN CANADA DIGS THRU SCENTRAL CANADA TOWARD THE UPR LKS...THE LLVL
FLOW WL TURN TO THE SSW. FCST SDNGS INDICATE ANY LINGERING LO CLDS
WL DSPT OR SHIFT OUT INTO LK SUP AND GIVE WAY TO A PERIOD OF MOCLR
CONDITIONS BEFORE CLDS ASSOCIATED WITH ISENTROPIC ASCENT AHEAD OF
THE APRCHG CLIPPER SHRTWV INVADE THE AREA NW TO SE. COMBINATION OF
EARLIER ARRIVING CLDS/STRENGTHENING SSW WIND WL TEND TO LIMIT THE
DIURNAL TEMP FALL OVER THE W. BUT OVER THE E...EXPECT TEMPS TO FALL
TOWARD THE LO END OF GUIDANCE BEFORE THE LATER ARRIVAL OF HI CLDS
AND STRENGTHENING FLOW OFF LK MI TENDS TO STOP THE TEMP FALL. THE
BULK OF THE MODELS ARE STILL HINTING THE LEADING EDGE OF THE WAA SN
WL REACH THE WRN CWA BY 12Z MON...SO RETAINED SOME CHC POPS THERE
LATE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 244 PM EST SUN JAN 25 2015
NAM SHOWS A DEEP 500 MB TROUGH OVER THE EASTERN U.S. WITH A STRONG
RIDGE OVER THE ROCKIES 00Z TUE. THIS RIDGE WEAKENS AS IT MOVES INTO
THE PLAINS ON TUE. NAM...GFS AND ECMWF SHOW 850-500 MB Q-VECTOR
CONVERGENCE MOVING INTO UPPER MICHIGAN ON WED.
WILL CONTINUE WITH CHANCE POPS FOR MON NIGHT AS A WEAK SYSTEM MOVES
THROUGH. THE MOISTURE FROM THIS SYSTEM DEPARTS ON TUE AND SHOULD BE
DRY FOR TUE NIGHT. ON WED...POPS WILL SLOWLY MOVE SOUTH ACROSS THE
CWA WITH CHANCE POPS ACROSS THE NORTHERN CWA BY LATE WED AFTERNOON.
DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST OVERALL.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB TROUGH OVER THE UPPER
GREAT LAKES 12Z THU WITH AN ALBERTA CLIPPER SYSTEM TO THE SOUTH OF
THE AREA. THIS CLIPPER WILL BRING IN SOME COLDER AIR ON FRI WITH
MORE UPPER TROUGHING FOR SAT WITH ANOTHER CLIPPER MOVING THROUGH THE
AREA. THIS CLIPPER HELPS TO CARVE OUT A BROAD AND DEEP 500 MB TROUGH
OVER THE EASTERN U.S. ON SUN. TEMPERATURES WILL FALL AND STAY BELOW
NORMAL FOR THIS FORECAST PERIOD. HAVE CHANCE POPS FOR WED NIGHT WITH
PASSAGE OF AN ALBERTA CLIPPER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1248 PM EST SUN JAN 25 2015
WEAKENING NORTHEASTERLY FLOW FROM A HIGH NEAR THUNDER BAY WILL LEAD
TO GRADUALLY DIMINISHING LAKE EFFECT CLOUDS AND SNOW SHOWERS AT
KCMX/KSAW THIS AFTERNOON AND EARLY EVENING. EXPECT THEIR CONDITIONS
TO BE PRIMARILY MVFR UNTIL THE HIGH SHIFTS EAST AND WINDS INCREASE
OUT OF THE SOUTH...LEADING TO CEILINGS RISING TO VFR. AT
KIWD...THEY HAVE SCATTERED OUT OVER THE LAST HOUR...BUT SATELLITE
AND WEBCAMS INDICATE BROKEN CLOUDS JUST UP STREAM. THUS...HAVE
STUCK WITH A MORE PESSIMISTIC MVFR CEILING TO START THE PERIOD
BEFORE ALSO TRENDING TO VFR.
A CLIPPER SYSTEM CURRENTLY OVER THE CANADIAN ROCKIES WILL QUICKLY
DROP SOUTHEAST ACROSS THE AREA LATE TONIGHT AND MONDAY. THIS WILL
LEAD TO GRADUALLY LOWERING CEILINGS AHEAD OF THE SYSTEM AND THEN SNOW
MOVING IN AT KIWD LATE TONIGHT AND KCMX/KSAW TOMORROW MORNING. THE
IFR VISIBILITIES WILL AFFECT KIWD LATE TONIGHT AND THEN KCMX TOWARDS
MID MORNING. HAVE HELD OFF ON LOWERING VISIBILITIES BELOW MVFR AT
KSAW DUE TO THE LATE ARRIVAL AND EXPECTED WEAKENING OF THE SNOW
HEADING INTO THE AFTERNOON.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 352 AM EST SUN JAN 25 2015
N TO NE WINDS UP TO 20-25 KTS THIS MORNING WILL DIMINISH THIS
AFTERNOON WITH ARRIVAL OF A HI PRES RIDGE. AS THE HI SHIFTS TO THE E
AND A LO PRES APPROACHES FROM THE NW TONIGHT AND MON...EXPECT
INCREASING S WINDS UP TO 25-30 KTS ON MON...STRONGEST OVER THE E
HALF OF THE LAKE. WINDS WILL THEN DIMINISH TO UNDER 20 KTS ON TUE
AND TUE NIGHT AS THE WEAKENING LO SLIDES TO THE SE AND A TRAILING HI
PRES RIDGE MOVES THRU THE UPPER LAKES. LIGHT S WINDS IN THE WAKE OF
THE DEPARTING HI ON WED WILL GIVE WAY STRENGTHENING N WINDS UP TO 25-
30 KTS ON THU FOLLOWING THE PASSAGE OF A LO PRES THRU THE LOWER
LAKES. THE ARRIVAL OF MUCH COLDER AIR AND INCREASING WAVES WILL
LIKELY RESULT IN SOME HEAVY FREEZING SPRAY BY LATE THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...07
AVIATION...SRF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1249 PM EST SUN JAN 25 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM EST SUN JAN 25 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALOFT
DOMINTING THE GREAT LKS BTWN HI AMPLITUDE RDG ALONG THE W COAST AND
A DEEP UPR TROF IN ERN NAMERICA CENTERED OVER NRN QUEBEC. SFC HI
PRES UNDER THIS NW FLOW IS BLDG SE THRU NW ONTARIO...WITH A COLD NNE
FLOW ON ITS SRN FLANK ADVECTING H85 TEMPS AS LO AS -15C OVER LK SUP
EARLY THIS MRNG. THE INFUSION OF THIS VERY COLD AIR OVER THE
RELATIVELY WARM LK SUP WATERS IS RESULTING IN SOME LK EFFECT SN
SHOWERS ACROSS MAINLY NCENTRAL UPR MI...WHERE THE LLVL FLOW IS
PRESENTING A MORE SGNFT UPSLOPE WIND COMPONENT. DESPITE FVRBL SN
GROWTH MICROPHYSICS WITH THE DGZ WITHIN MUCH OF THE CONVECTIVE
LYR...HI STABILITY/DRYNESS OF INCOMING AIRMASS PER THE 00Z YPL
RAOB...WHERE THE 00Z PWAT WAS ONLY 0.05 INCH AND THE SUBSIDENCE
INVRN WAS LOCATED NEAR H9 /MQT VWP INDICATES THE INVRN BASE HERE IS
NEAR 3K FT AGL/...AS WELL AS THE LARGER SCALE ACYC FLOW THAT IS
MINIMIZING LLVL CNVGC IS TENDING TO LIMIT THE INTENSITY OF THE LES.
OVER THE E...SKIES HAVE BEGUN TO CLEAR AT NEWBERRY WITH MINIMAL
OVERWATER TRAJECTORY AND SOME DOWNSLOPING OF THE LLVL NE FLOW OFF
ONTARIO...WHERE SFC DEWPTS EARLY THIS MRNG ARE AS LO AS -20 TO -25F
TO THE N OF LK SUP. LOOKING FARTHER UPSTREAM...A FAIRLY STRONG
SHRTWV IS MOVING THRU WRN CANADA OVER TOP THE WRN RDG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS ASSOCIATED WITH
THE COLD NE LLVL FLOW THAT WL PERSIST INTO THIS AFTN. FOCUS FOR TNGT
SHIFTS TO LO TEMPS AND SN CHCS LATE OVER THE W ASSOCIATED WITH
DISTURBANCE NOW TRACKING THRU WRN CANADA.
TODAY...SFC HI PRES CENTER IS FCST TO DRIFT SLOWLY TO THE SE OVER
FAR NE LK SUP BY 00Z MON. LLVL NE FLOW WL PERSIST THRU THIS
MRNG...BUT THEN WEAKEN AS THE HI CENTER MOVES CLOSER AND SFC RDG
AXIS EXTENDING TO THE SW MOVES OVHD BY 00Z. WITH THE -15C H85
ISOTHERM OVER CENTRAL LK SUP AND THE DGZ IN THE 1-3K FT LYR
ENCOMPASSING MUCH OF THE CONVECTIVE LYR...SOME FLUFFY LES WL PERSIST
IN THE NE SN BELTS OVER MAINLY THE NCENTRAL. DESPITE THE PRESENCE OF
THE DGZ AND SUFFICIENT CHILL OF THE AIRMASS...INVRN BASE NEAR 3K FT
AGL AND ACYC NATURE OF THE H925 FLOW WL CONTINUE TO LIMIT ADDITIONAL
SN ACCUMS TO AN INCH OR LESS. DURING THE AFTN WHEN THE WINDS/UPSLOPE
FORCING DIMINISH FURTHER AND THE SFC RDG AXIS BECOMES MORE
PRONOUNCED...THE LES SHOULD TEND TO DIMINISH EVEN FURTHER. THE ERN
CWA SHOULD BE MOSUNNY WITH DOWNSLOPE FLOW/MINIMAL OVERWATER
TRAJECTORY OF THE DRY AIRMASS. NEAR THE WI BORDER...SOME BREAKS IN
THE SC OVC ARE LIKELY BY MID/LATE AFTN WITH THE CLOSER APRCH OF THE
SFC RDG AXIS. BUT EVEN WHERE THE SUN COMES OUT...HI TEMPS WL BE HARD
PRESSED TO RISE OUT OF THE TEENS PER OBSVD HI TEMPS IN ONTARIO YDAY.
TNGT...AS THE SFC RDG AXIS SHIFTS TO THE E AND THE SHRTWV NOW OVER
WRN CANADA DIGS THRU SCENTRAL CANADA TOWARD THE UPR LKS...THE LLVL
FLOW WL TURN TO THE SSW. FCST SDNGS INDICATE ANY LINGERING LO CLDS
WL DSPT OR SHIFT OUT INTO LK SUP AND GIVE WAY TO A PERIOD OF MOCLR
CONDITIONS BEFORE CLDS ASSOCIATED WITH ISENTROPIC ASCENT AHEAD OF
THE APRCHG CLIPPER SHRTWV INVADE THE AREA NW TO SE. COMBINATION OF
EARLIER ARRIVING CLDS/STRENGTHENING SSW WIND WL TEND TO LIMIT THE
DIURNAL TEMP FALL OVER THE W. BUT OVER THE E...EXPECT TEMPS TO FALL
TOWARD THE LO END OF GUIDANCE BEFORE THE LATER ARRIVAL OF HI CLDS
AND STRENGTHENING FLOW OFF LK MI TENDS TO STOP THE TEMP FALL. THE
BULK OF THE MODELS ARE STILL HINTING THE LEADING EDGE OF THE WAA SN
WL REACH THE WRN CWA BY 12Z MON...SO RETAINED SOME CHC POPS THERE
LATE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 340 AM EST SUN JAN 25 2015
EXPECT NO SIGNIFICANT PATTERN CHANGES THROUGH THE PERIOD...AS A
500MB TROUGH LINGERS ACROSS EASTERN CANADA AND MUCH OF THE EAST HALF
OF THE U.S. THE MAIN EXCEPTION WILL BE TUESDAY THROUGH WEDNESDAY AS
THE RIDGE ACROSS THE WEST MOVES ACROSS THE PLAINS AND GREAT LAKES
REGION. BY 00Z THURSDAY 850MB TEMPS SHOULD WARM TO -4 TO -1C
/WARMEST OFF THE 24/12Z ECMWF/. SFC TEMPS TOPPING OUT NEAR FREEZING
WILL BE THE RESULT WEDNESDAY AFTERNOON. THE WARM SPELL WILL BE SHORT
LIVED AS COLDER AIR SET UP OVER N CENTRAL CANADA SHIFTS SINKS ACROSS
HUDSON BAY ON FRIDAY...AND SURGE ACROSS ONTARIO AND INTO THE UPPER
GREAT LAKES FROM SATURDAY THROUGH THE START OF THE NEXT WORK WEEK.
THE EXACT TIMING...SATURDAY OR LATER SATURDAY NIGHT...IS STILL IN
QUESTION. THE 25/00Z IS A LITTLE SLOWER TO PUSH THE COLD AIR DOWN.
GIVEN THAT THIS IS OVER 150HRS OUT...WILL GO WITH A BLENDED SOLUTION
FOR NOW.
AS FOR SOME OF THE SPECIFICS...WE WILL START 12Z MONDAY WITH THE
NEXT LOW KNOCKING ON THE DOOR /SET UP ACROSS SE MANITOBA THROUGH N
MN/. THE CANADIAN AND ECMWF ARE ON THE SW END OF THE LOW TRACK
ENVELOPE...WHILE THE NAM AND GFS ARE FARTHER TO THE NE AND TRACK IT
OVER W LAKE SUPERIR BY 00Z TUESDAY. EITHER WAY THE ROUGHLY 150 MILE
DIFFERNECE IN PLACMENT OF THE LOW DOES MAKE A DIFFERENCE IN THE WIND
FIELDS...BUT BOTH INDICATE SNOW FOR WESTERN AND AT LEAST MOST OF
CENTRAL UPPER MI. THIS SW TREND IN THE BETTER FORCING OCCURRED WITH
THE LAST SIGNIFICANT CLIPPER SYSTEM TOO...SO WE WILL SEE IF THIS
CONTINUES. WILL KEEP THE LIKELY POPS IN THE W ONLY.
BEHIND THE LOW A SFC RIDGE WILL SLIDE ACROSS UPPER MI FROM THE
W...AS THE NEXT LOW ORGANIZES ACROSS THE PLAINS STATES
TUESDAY/WEDNESAY. EXPECT THIS LOW /EXTENDING FROM ND ALL THE WAY
THROUGH N TX AT 18Z WEDNESDAY TO PUSH ACROSS FAR S LAKE MI BY
DAYBREAK THURSDAY. THERE IS AMAZING CONSISTANCY WITH THE TRACK AND
STRENGTH OF THIS LOW FOR THIS 108HR FCST. THE INVERTED TROUGH WILL
EXTEND ALL THE WAY THROUGH N LAKE SUPERIOR 00-12Z THURSDAY. THIS
WILL BE THE FOCUS FOR SNOW...ASSISTED BY THE NEXT ELONGATED
SHORTWAVE SWINGING IN FROM THE NW. AT THIS POINT THE GFS IS HINTING
IN 3-5IN OF SNOW FROM 00Z THURSDAY THROUGH 00Z FRIDAY...BEFORE THE
INVERSION HEIGHTS START DROPPING BELOW 5KFT AS STRONG HIGH PRESSURE
BEGINS TO BUILD IN FROM THE NW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1248 PM EST SUN JAN 25 2015
WEAKENING NORTHEASTERLY FLOW FROM A HIGH NEAR THUNDER BAY WILL LEAD
TO GRADUALLY DIMINISHING LAKE EFFECT CLOUDS AND SNOW SHOWERS AT
KCMX/KSAW THIS AFTERNOON AND EARLY EVENING. EXPECT THEIR CONDITIONS
TO BE PRIMARILY MVFR UNTIL THE HIGH SHIFTS EAST AND WINDS INCREASE
OUT OF THE SOUTH...LEADING TO CEILINGS RISING TO VFR. AT
KIWD...THEY HAVE SCATTERED OUT OVER THE LAST HOUR...BUT SATELLITE
AND WEBCAMS INDICATE BROKEN CLOUDS JUST UP STREAM. THUS...HAVE
STUCK WITH A MORE PESSIMISTIC MVFR CEILING TO START THE PERIOD
BEFORE ALSO TRENDING TO VFR.
A CLIPPER SYSTEM CURRENTLY OVER THE CANADIAN ROCKIES WILL QUICKLY
DROP SOUTHEAST ACROSS THE AREA LATE TONIGHT AND MONDAY. THIS WILL
LEAD TO GRADUALLY LOWERING CEILINGS AHEAD OF THE SYSTEM AND THEN SNOW
MOVING IN AT KIWD LATE TONIGHT AND KCMX/KSAW TOMORROW MORNING. THE
IFR VISIBILITIES WILL AFFECT KIWD LATE TONIGHT AND THEN KCMX TOWARDS
MID MORNING. HAVE HELD OFF ON LOWERING VISIBILITIES BELOW MVFR AT
KSAW DUE TO THE LATE ARRIVAL AND EXPECTED WEAKENING OF THE SNOW
HEADING INTO THE AFTERNOON.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 352 AM EST SUN JAN 25 2015
N TO NE WINDS UP TO 20-25 KTS THIS MORNING WILL DIMINISH THIS
AFTERNOON WITH ARRIVAL OF A HI PRES RIDGE. AS THE HI SHIFTS TO THE E
AND A LO PRES APPROACHES FROM THE NW TONIGHT AND MON...EXPECT
INCREASING S WINDS UP TO 25-30 KTS ON MON...STRONGEST OVER THE E
HALF OF THE LAKE. WINDS WILL THEN DIMINISH TO UNDER 20 KTS ON TUE
AND TUE NIGHT AS THE WEAKENING LO SLIDES TO THE SE AND A TRAILING HI
PRES RIDGE MOVES THRU THE UPPER LAKES. LIGHT S WINDS IN THE WAKE OF
THE DEPARTING HI ON WED WILL GIVE WAY STRENGTHENING N WINDS UP TO 25-
30 KTS ON THU FOLLOWING THE PASSAGE OF A LO PRES THRU THE LOWER
LAKES. THE ARRIVAL OF MUCH COLDER AIR AND INCREASING WAVES WILL
LIKELY RESULT IN SOME HEAVY FREEZING SPRAY BY LATE THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...SRF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
628 AM EST SUN JAN 25 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM EST SUN JAN 25 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALOFT
DOMINTING THE GREAT LKS BTWN HI AMPLITUDE RDG ALONG THE W COAST AND
A DEEP UPR TROF IN ERN NAMERICA CENTERED OVER NRN QUEBEC. SFC HI
PRES UNDER THIS NW FLOW IS BLDG SE THRU NW ONTARIO...WITH A COLD NNE
FLOW ON ITS SRN FLANK ADVECTING H85 TEMPS AS LO AS -15C OVER LK SUP
EARLY THIS MRNG. THE INFUSION OF THIS VERY COLD AIR OVER THE
RELATIVELY WARM LK SUP WATERS IS RESULTING IN SOME LK EFFECT SN
SHOWERS ACROSS MAINLY NCENTRAL UPR MI...WHERE THE LLVL FLOW IS
PRESENTING A MORE SGNFT UPSLOPE WIND COMPONENT. DESPITE FVRBL SN
GROWTH MICROPHYSICS WITH THE DGZ WITHIN MUCH OF THE CONVECTIVE
LYR...HI STABILITY/DRYNESS OF INCOMING AIRMASS PER THE 00Z YPL
RAOB...WHERE THE 00Z PWAT WAS ONLY 0.05 INCH AND THE SUBSIDENCE
INVRN WAS LOCATED NEAR H9 /MQT VWP INDICATES THE INVRN BASE HERE IS
NEAR 3K FT AGL/...AS WELL AS THE LARGER SCALE ACYC FLOW THAT IS
MINIMIZING LLVL CNVGC IS TENDING TO LIMIT THE INTENSITY OF THE LES.
OVER THE E...SKIES HAVE BEGUN TO CLEAR AT NEWBERRY WITH MINIMAL
OVERWATER TRAJECTORY AND SOME DOWNSLOPING OF THE LLVL NE FLOW OFF
ONTARIO...WHERE SFC DEWPTS EARLY THIS MRNG ARE AS LO AS -20 TO -25F
TO THE N OF LK SUP. LOOKING FARTHER UPSTREAM...A FAIRLY STRONG
SHRTWV IS MOVING THRU WRN CANADA OVER TOP THE WRN RDG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS ASSOCIATED WITH
THE COLD NE LLVL FLOW THAT WL PERSIST INTO THIS AFTN. FOCUS FOR TNGT
SHIFTS TO LO TEMPS AND SN CHCS LATE OVER THE W ASSOCIATED WITH
DISTURBANCE NOW TRACKING THRU WRN CANADA.
TODAY...SFC HI PRES CENTER IS FCST TO DRIFT SLOWLY TO THE SE OVER
FAR NE LK SUP BY 00Z MON. LLVL NE FLOW WL PERSIST THRU THIS
MRNG...BUT THEN WEAKEN AS THE HI CENTER MOVES CLOSER AND SFC RDG
AXIS EXTENDING TO THE SW MOVES OVHD BY 00Z. WITH THE -15C H85
ISOTHERM OVER CENTRAL LK SUP AND THE DGZ IN THE 1-3K FT LYR
ENCOMPASSING MUCH OF THE CONVECTIVE LYR...SOME FLUFFY LES WL PERSIST
IN THE NE SN BELTS OVER MAINLY THE NCENTRAL. DESPITE THE PRESENCE OF
THE DGZ AND SUFFICIENT CHILL OF THE AIRMASS...INVRN BASE NEAR 3K FT
AGL AND ACYC NATURE OF THE H925 FLOW WL CONTINUE TO LIMIT ADDITIONAL
SN ACCUMS TO AN INCH OR LESS. DURING THE AFTN WHEN THE WINDS/UPSLOPE
FORCING DIMINISH FURTHER AND THE SFC RDG AXIS BECOMES MORE
PRONOUNCED...THE LES SHOULD TEND TO DIMINISH EVEN FURTHER. THE ERN
CWA SHOULD BE MOSUNNY WITH DOWNSLOPE FLOW/MINIMAL OVERWATER
TRAJECTORY OF THE DRY AIRMASS. NEAR THE WI BORDER...SOME BREAKS IN
THE SC OVC ARE LIKELY BY MID/LATE AFTN WITH THE CLOSER APRCH OF THE
SFC RDG AXIS. BUT EVEN WHERE THE SUN COMES OUT...HI TEMPS WL BE HARD
PRESSED TO RISE OUT OF THE TEENS PER OBSVD HI TEMPS IN ONTARIO YDAY.
TNGT...AS THE SFC RDG AXIS SHIFTS TO THE E AND THE SHRTWV NOW OVER
WRN CANADA DIGS THRU SCENTRAL CANADA TOWARD THE UPR LKS...THE LLVL
FLOW WL TURN TO THE SSW. FCST SDNGS INDICATE ANY LINGERING LO CLDS
WL DSPT OR SHIFT OUT INTO LK SUP AND GIVE WAY TO A PERIOD OF MOCLR
CONDITIONS BEFORE CLDS ASSOCIATED WITH ISENTROPIC ASCENT AHEAD OF
THE APRCHG CLIPPER SHRTWV INVADE THE AREA NW TO SE. COMBINATION OF
EARLIER ARRIVING CLDS/STRENGTHENING SSW WIND WL TEND TO LIMIT THE
DIURNAL TEMP FALL OVER THE W. BUT OVER THE E...EXPECT TEMPS TO FALL
TOWARD THE LO END OF GUIDANCE BEFORE THE LATER ARRIVAL OF HI CLDS
AND STRENGTHENING FLOW OFF LK MI TENDS TO STOP THE TEMP FALL. THE
BULK OF THE MODELS ARE STILL HINTING THE LEADING EDGE OF THE WAA SN
WL REACH THE WRN CWA BY 12Z MON...SO RETAINED SOME CHC POPS THERE
LATE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 340 AM EST SUN JAN 25 2015
EXPECT NO SIGNIFICANT PATTERN CHANGES THROUGH THE PERIOD...AS A
500MB TROUGH LINGERS ACROSS EASTERN CANADA AND MUCH OF THE EAST HALF
OF THE U.S. THE MAIN EXCEPTION WILL BE TUESDAY THROUGH WEDNESDAY AS
THE RIDGE ACROSS THE WEST MOVES ACROSS THE PLAINS AND GREAT LAKES
REGION. BY 00Z THURSDAY 850MB TEMPS SHOULD WARM TO -4 TO -1C
/WARMEST OFF THE 24/12Z ECMWF/. SFC TEMPS TOPPING OUT NEAR FREEZING
WILL BE THE RESULT WEDNESDAY AFTERNOON. THE WARM SPELL WILL BE SHORT
LIVED AS COLDER AIR SET UP OVER N CENTRAL CANADA SHIFTS SINKS ACROSS
HUDSON BAY ON FRIDAY...AND SURGE ACROSS ONTARIO AND INTO THE UPPER
GREAT LAKES FROM SATURDAY THROUGH THE START OF THE NEXT WORK WEEK.
THE EXACT TIMING...SATURDAY OR LATER SATURDAY NIGHT...IS STILL IN
QUESTION. THE 25/00Z IS A LITTLE SLOWER TO PUSH THE COLD AIR DOWN.
GIVEN THAT THIS IS OVER 150HRS OUT...WILL GO WITH A BLENDED SOLUTION
FOR NOW.
AS FOR SOME OF THE SPECIFICS...WE WILL START 12Z MONDAY WITH THE
NEXT LOW KNOCKING ON THE DOOR /SET UP ACROSS SE MANITOBA THROUGH N
MN/. THE CANADIAN AND ECMWF ARE ON THE SW END OF THE LOW TRACK
ENVELOPE...WHILE THE NAM AND GFS ARE FARTHER TO THE NE AND TRACK IT
OVER W LAKE SUPERIR BY 00Z TUESDAY. EITHER WAY THE ROUGHLY 150 MILE
DIFFERNECE IN PLACMENT OF THE LOW DOES MAKE A DIFFERENCE IN THE WIND
FIELDS...BUT BOTH INDICATE SNOW FOR WESTERN AND AT LEAST MOST OF
CENTRAL UPPER MI. THIS SW TREND IN THE BETTER FORCING OCCURRED WITH
THE LAST SIGNIFICANT CLIPPER SYSTEM TOO...SO WE WILL SEE IF THIS
CONTINUES. WILL KEEP THE LIKELY POPS IN THE W ONLY.
BEHIND THE LOW A SFC RIDGE WILL SLIDE ACROSS UPPER MI FROM THE
W...AS THE NEXT LOW ORGANIZES ACROSS THE PLAINS STATES
TUESDAY/WEDNESAY. EXPECT THIS LOW /EXTENDING FROM ND ALL THE WAY
THROUGH N TX AT 18Z WEDNESDAY TO PUSH ACROSS FAR S LAKE MI BY
DAYBREAK THURSDAY. THERE IS AMAZING CONSISTANCY WITH THE TRACK AND
STRENGTH OF THIS LOW FOR THIS 108HR FCST. THE INVERTED TROUGH WILL
EXTEND ALL THE WAY THROUGH N LAKE SUPERIOR 00-12Z THURSDAY. THIS
WILL BE THE FOCUS FOR SNOW...ASSISTED BY THE NEXT ELONGATED
SHORTWAVE SWINGING IN FROM THE NW. AT THIS POINT THE GFS IS HINTING
IN 3-5IN OF SNOW FROM 00Z THURSDAY THROUGH 00Z FRIDAY...BEFORE THE
INVERSION HEIGHTS START DROPPING BELOW 5KFT AS STRONG HIGH PRESSURE
BEGINS TO BUILD IN FROM THE NW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 628 AM EST SUN JAN 25 2015
A MOIST NE FLOW TO THE S OF HI PRES IN NW ONTARIO AND UNDER LO
SUBSIDENCE INVRN WL RESULT IN MVFR CIGS AT ALL 3 TAF SITES INTO THIS
AFTN. AS THE HI PRES RDG MOVES INTO UPR MI LATER TODAY...THE LO CLDS
WL DISSIPATE AND GIVE WAY TO VFR CONDITIONS. BUT MID/HI CLDS WL
MOVE IN TNGT WITH RETURNING MSTR IN THE S FLOW AHEAD OF ANOTHER LO
PRES MOVING SEWD THRU SCENTRAL CANADA. SOME -SN/MVFR CONDITIONS IN
ADVANCE OF THIS DISTURBANCE WL ARRIVE LATE AT IWD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 352 AM EST SUN JAN 25 2015
N TO NE WINDS UP TO 20-25 KTS THIS MORNING WILL DIMINISH THIS
AFTERNOON WITH ARRIVAL OF A HI PRES RIDGE. AS THE HI SHIFTS TO THE E
AND A LO PRES APPROACHES FROM THE NW TONIGHT AND MON...EXPECT
INCREASING S WINDS UP TO 25-30 KTS ON MON...STRONGEST OVER THE E
HALF OF THE LAKE. WINDS WILL THEN DIMINISH TO UNDER 20 KTS ON TUE
AND TUE NIGHT AS THE WEAKENING LO SLIDES TO THE SE AND A TRAILING HI
PRES RIDGE MOVES THRU THE UPPER LAKES. LIGHT S WINDS IN THE WAKE OF
THE DEPARTING HI ON WED WILL GIVE WAY STRENGTHENING N WINDS UP TO 25-
30 KTS ON THU FOLLOWING THE PASSAGE OF A LO PRES THRU THE LOWER
LAKES. THE ARRIVAL OF MUCH COLDER AIR AND INCREASING WAVES WILL
LIKELY RESULT IN SOME HEAVY FREEZING SPRAY BY LATE THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
352 AM EST SUN JAN 25 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 352 AM EST SUN JAN 25 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALOFT
DOMINTING THE GREAT LKS BTWN HI AMPLITUDE RDG ALONG THE W COAST AND
A DEEP UPR TROF IN ERN NAMERICA CENTERED OVER NRN QUEBEC. SFC HI
PRES UNDER THIS NW FLOW IS BLDG SE THRU NW ONTARIO...WITH A COLD NNE
FLOW ON ITS SRN FLANK ADVECTING H85 TEMPS AS LO AS -15C OVER LK SUP
EARLY THIS MRNG. THE INFUSION OF THIS VERY COLD AIR OVER THE
RELATIVELY WARM LK SUP WATERS IS RESULTING IN SOME LK EFFECT SN
SHOWERS ACROSS MAINLY NCENTRAL UPR MI...WHERE THE LLVL FLOW IS
PRESENTING A MORE SGNFT UPSLOPE WIND COMPONENT. DESPITE FVRBL SN
GROWTH MICROPHYSICS WITH THE DGZ WITHIN MUCH OF THE CONVECTIVE
LYR...HI STABILITY/DRYNESS OF INCOMING AIRMASS PER THE 00Z YPL
RAOB...WHERE THE 00Z PWAT WAS ONLY 0.05 INCH AND THE SUBSIDENCE
INVRN WAS LOCATED NEAR H9 /MQT VWP INDICATES THE INVRN BASE HERE IS
NEAR 3K FT AGL/...AS WELL AS THE LARGER SCALE ACYC FLOW THAT IS
MINIMIZING LLVL CNVGC IS TENDING TO LIMIT THE INTENSITY OF THE LES.
OVER THE E...SKIES HAVE BEGUN TO CLEAR AT NEWBERRY WITH MINIMAL
OVERWATER TRAJECTORY AND SOME DOWNSLOPING OF THE LLVL NE FLOW OFF
ONTARIO...WHERE SFC DEWPTS EARLY THIS MRNG ARE AS LO AS -20 TO -25F
TO THE N OF LK SUP. LOOKING FARTHER UPSTREAM...A FAIRLY STRONG
SHRTWV IS MOVING THRU WRN CANADA OVER TOP THE WRN RDG.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS ASSOCIATED WITH
THE COLD NE LLVL FLOW THAT WL PERSIST INTO THIS AFTN. FOCUS FOR TNGT
SHIFTS TO LO TEMPS AND SN CHCS LATE OVER THE W ASSOCIATED WITH
DISTURBANCE NOW TRACKING THRU WRN CANADA.
TODAY...SFC HI PRES CENTER IS FCST TO DRIFT SLOWLY TO THE SE OVER
FAR NE LK SUP BY 00Z MON. LLVL NE FLOW WL PERSIST THRU THIS
MRNG...BUT THEN WEAKEN AS THE HI CENTER MOVES CLOSER AND SFC RDG
AXIS EXTENDING TO THE SW MOVES OVHD BY 00Z. WITH THE -15C H85
ISOTHERM OVER CENTRAL LK SUP AND THE DGZ IN THE 1-3K FT LYR
ENCOMPASSING MUCH OF THE CONVECTIVE LYR...SOME FLUFFY LES WL PERSIST
IN THE NE SN BELTS OVER MAINLY THE NCENTRAL. DESPITE THE PRESENCE OF
THE DGZ AND SUFFICIENT CHILL OF THE AIRMASS...INVRN BASE NEAR 3K FT
AGL AND ACYC NATURE OF THE H925 FLOW WL CONTINUE TO LIMIT ADDITIONAL
SN ACCUMS TO AN INCH OR LESS. DURING THE AFTN WHEN THE WINDS/UPSLOPE
FORCING DIMINISH FURTHER AND THE SFC RDG AXIS BECOMES MORE
PRONOUNCED...THE LES SHOULD TEND TO DIMINISH EVEN FURTHER. THE ERN
CWA SHOULD BE MOSUNNY WITH DOWNSLOPE FLOW/MINIMAL OVERWATER
TRAJECTORY OF THE DRY AIRMASS. NEAR THE WI BORDER...SOME BREAKS IN
THE SC OVC ARE LIKELY BY MID/LATE AFTN WITH THE CLOSER APRCH OF THE
SFC RDG AXIS. BUT EVEN WHERE THE SUN COMES OUT...HI TEMPS WL BE HARD
PRESSED TO RISE OUT OF THE TEENS PER OBSVD HI TEMPS IN ONTARIO YDAY.
TNGT...AS THE SFC RDG AXIS SHIFTS TO THE E AND THE SHRTWV NOW OVER
WRN CANADA DIGS THRU SCENTRAL CANADA TOWARD THE UPR LKS...THE LLVL
FLOW WL TURN TO THE SSW. FCST SDNGS INDICATE ANY LINGERING LO CLDS
WL DSPT OR SHIFT OUT INTO LK SUP AND GIVE WAY TO A PERIOD OF MOCLR
CONDITIONS BEFORE CLDS ASSOCIATED WITH ISENTROPIC ASCENT AHEAD OF
THE APRCHG CLIPPER SHRTWV INVADE THE AREA NW TO SE. COMBINATION OF
EARLIER ARRIVING CLDS/STRENGTHENING SSW WIND WL TEND TO LIMIT THE
DIURNAL TEMP FALL OVER THE W. BUT OVER THE E...EXPECT TEMPS TO FALL
TOWARD THE LO END OF GUIDANCE BEFORE THE LATER ARRIVAL OF HI CLDS
AND STRENGTHENING FLOW OFF LK MI TENDS TO STOP THE TEMP FALL. THE
BULK OF THE MODELS ARE STILL HINTING THE LEADING EDGE OF THE WAA SN
WL REACH THE WRN CWA BY 12Z MON...SO RETAINED SOME CHC POPS THERE
LATE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 340 AM EST SUN JAN 25 2015
EXPECT NO SIGNIFICANT PATTERN CHANGES THROUGH THE PERIOD...AS A
500MB TROUGH LINGERS ACROSS EASTERN CANADA AND MUCH OF THE EAST HALF
OF THE U.S. THE MAIN EXCEPTION WILL BE TUESDAY THROUGH WEDNESDAY AS
THE RIDGE ACROSS THE WEST MOVES ACROSS THE PLAINS AND GREAT LAKES
REGION. BY 00Z THURSDAY 850MB TEMPS SHOULD WARM TO -4 TO -1C
/WARMEST OFF THE 24/12Z ECMWF/. SFC TEMPS TOPPING OUT NEAR FREEZING
WILL BE THE RESULT WEDNESDAY AFTERNOON. THE WARM SPELL WILL BE SHORT
LIVED AS COLDER AIR SET UP OVER N CENTRAL CANADA SHIFTS SINKS ACROSS
HUDSON BAY ON FRIDAY...AND SURGE ACROSS ONTARIO AND INTO THE UPPER
GREAT LAKES FROM SATURDAY THROUGH THE START OF THE NEXT WORK WEEK.
THE EXACT TIMING...SATURDAY OR LATER SATURDAY NIGHT...IS STILL IN
QUESTION. THE 25/00Z IS A LITTLE SLOWER TO PUSH THE COLD AIR DOWN.
GIVEN THAT THIS IS OVER 150HRS OUT...WILL GO WITH A BLENDED SOLUTION
FOR NOW.
AS FOR SOME OF THE SPECIFICS...WE WILL START 12Z MONDAY WITH THE
NEXT LOW KNOCKING ON THE DOOR /SET UP ACROSS SE MANITOBA THROUGH N
MN/. THE CANADIAN AND ECMWF ARE ON THE SW END OF THE LOW TRACK
ENVELOPE...WHILE THE NAM AND GFS ARE FARTHER TO THE NE AND TRACK IT
OVER W LAKE SUPERIR BY 00Z TUESDAY. EITHER WAY THE ROUGHLY 150 MILE
DIFFERNECE IN PLACMENT OF THE LOW DOES MAKE A DIFFERENCE IN THE WIND
FIELDS...BUT BOTH INDICATE SNOW FOR WESTERN AND AT LEAST MOST OF
CENTRAL UPPER MI. THIS SW TREND IN THE BETTER FORCING OCCURRED WITH
THE LAST SIGNIFICANT CLIPPER SYSTEM TOO...SO WE WILL SEE IF THIS
CONTINUES. WILL KEEP THE LIKELY POPS IN THE W ONLY.
BEHIND THE LOW A SFC RIDGE WILL SLIDE ACROSS UPPER MI FROM THE
W...AS THE NEXT LOW ORGANIZES ACROSS THE PLAINS STATES
TUESDAY/WEDNESAY. EXPECT THIS LOW /EXTENDING FROM ND ALL THE WAY
THROUGH N TX AT 18Z WEDNESDAY TO PUSH ACROSS FAR S LAKE MI BY
DAYBREAK THURSDAY. THERE IS AMAZING CONSISTANCY WITH THE TRACK AND
STRENGTH OF THIS LOW FOR THIS 108HR FCST. THE INVERTED TROUGH WILL
EXTEND ALL THE WAY THROUGH N LAKE SUPERIOR 00-12Z THURSDAY. THIS
WILL BE THE FOCUS FOR SNOW...ASSISTED BY THE NEXT ELONGATED
SHORTWAVE SWINGING IN FROM THE NW. AT THIS POINT THE GFS IS HINTING
IN 3-5IN OF SNOW FROM 00Z THURSDAY THROUGH 00Z FRIDAY...BEFORE THE
INVERSION HEIGHTS START DROPPING BELOW 5KFT AS STRONG HIGH PRESSURE
BEGINS TO BUILD IN FROM THE NW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1225 AM EST SUN JAN 25 2015
A MOIST NE LOW-LVL WIND DIRECTION OVER THE AREA SHOULD MAINTAIN MVFR
CIGS THROUGH MUCH OF THE PD FOR ALL TAF SITES. NE WIND DIRECTION WILL
FAVOR MAINLY KSAW FOR LIGHT LAKE EFFECT SNOW SHOWERS INTO SUNDAY BUT
DO NOT EXPECT MUCH VSBY RESTRICTION FROM -SHSN. EXPECT WINDS TO GO
VARIABLE AT KIWD AND KCMX LATE SUNDAY AND AT KSAW TOWARD SUN EVENING
WITH IMPROVEMENT TO VFR CONDITIONS AS HIGH PRES BUILDS IN FM NW OF
LAKE SUPERIOR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 352 AM EST SUN JAN 25 2015
N TO NE WINDS UP TO 20-25 KTS THIS MORNING WILL DIMINISH THIS
AFTERNOON WITH ARRIVAL OF A HI PRES RIDGE. AS THE HI SHIFTS TO THE E
AND A LO PRES APPROACHES FROM THE NW TONIGHT AND MON...EXPECT
INCREASING S WINDS UP TO 25-30 KTS ON MON...STRONGEST OVER THE E
HALF OF THE LAKE. WINDS WILL THEN DIMINISH TO UNDER 20 KTS ON TUE
AND TUE NIGHT AS THE WEAKENING LO SLIDES TO THE SE AND A TRAILING HI
PRES RIDGE MOVES THRU THE UPPER LAKES. LIGHT S WINDS IN THE WAKE OF
THE DEPARTING HI ON WED WILL GIVE WAY STRENGTHENING N WINDS UP TO 25-
30 KTS ON THU FOLLOWING THE PASSAGE OF A LO PRES THRU THE LOWER
LAKES. THE ARRIVAL OF MUCH COLDER AIR AND INCREASING WAVES WILL
LIKELY RESULT IN SOME HEAVY FREEZING SPRAY BY LATE THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
604 PM CST MON JAN 26 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 343 PM CST MON JAN 26 2015
A SURFACE LOW ANALYZED BY THE RAP NEAR DULUTH THIS AFTERNOON WITH A
STALLED WARM FRONT THROUGH EXTREME WESTERN WI...JUST EAST OF THE MN
BORDER. TEMPERATURES WEST OF THE FRONT HAVE CLIMBED WELL INTO THE
40S ACROSS MOST OF THE REGION WITH DEW POINTS IN THE LOW TO MID 30S.
THIS CAUSES SOME CONCERN FOR FOG DEVELOPMENT OVERNIGHT AS A SURFACE
HIGH/RIDGE AXIS MOVES IN LATE TONIGHT AND WINDS GO NEARLY CALM. THE
TRICKY PART OF THE FORECAST IS HOW FAR WEST THE CLOUD COVER WILL
EXTEND TONIGHT. MODEL GUIDANCE IS QUITE SATURATED AT 925MB BUT CAN
EASILY IMPACTED BY SURFACE MOISTURE. AN INVERSION WILL DEVELOP
AFTER DARK AND COULD LOCK ANY LOW CLOUD COVER IN PLACE. CONFIDENCE
IS LOW IN CLOUD COVER ACROSS WESTERN MN.
IN WEST CENTRAL WISCONSIN...EAST OF THE FRONT...TEMPERATURES HAVE
HELD STEADY IN THE MID 20S WITH -FZDZ AND -SN BEING REPORTED THROUGH
MUCH OF THE DAY. VERY LIGHT AND SCATTER PRECIP WILL CONTINUE MOVING
THROUGH THIS AREA ALONG THE FRONTAL BOUNDARY FOR THE NEXT FEW HOURS.
OTHERWISE...COOLED TEMPS SLIGHTLY FOR TOMORROW ACROSS THE EAST GIVEN
LINGERING CLOUD COVER...AND THE FACT THE SOUTHERLY WINDS ON THE BACK
SIDE OF THE RIDGE DONT ARRIVE UNTIL LATE IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 343 PM CST MON JAN 26 2015
A COUPLE CHANCES FOR LIGHT PRECIPITATION EXIST IN THE EXTENDED
PERIOD OF THE FORECAST...WHILE THE COOLDOWN REMAINS ON TRACK FOR THE
WEEKEND AND INTO EARLY NEXT WEEK.
EARLY AFTERNOON WATERVAPOR IMAGERY TOGETHER WITH GFS 500MB HEIGHTS
AND WINDS SHOWED A BROAD AREA OF NORTHEAST FLOW ACROSS THE CENTRAL
CONUS SANDWICHED BETWEEN THE NEGATIVELY TILTED RIDGE ALONG THE
SPINE OF THE ROCKIES...AND MORE NOTABLY THE NEGATIVE TILTED UPPER
LEVEL TROUGH DRIVING THE POWERFUL NOREASTER OVER THE NEW ENGLAND
AREA. THIS NORTHWEST FLOW PATTERN WILL GENERALLY REMAIN IN PLACE
ACROSS THE UPPER MIDWEST...WITH PERIODIC SHORTWAVES BRINGING
REPEATED CHANCES FOR LIGHT PRECIP.
THE FIRST WILL ARRIVE WEDNESDAY NIGHT...AND THERMAL PROFILES SHOW
THE POTENTIAL FOR A WINTRY MIX OF LIGHT SNOW OR FREEZING DRIZZLE.
NOTE...WEDNEDAYS HIGH TEMPERATURE WILL DEPEND HEAVILY ON CLOUD
COVER...SO DID NOT WARM TEMPS SINCE MID/LOW LEVEL CLOUDS SHOULD KEEP
AFTERNOON HIGHS FROM WARMING OUT OF CONTROL DESPITE THE FAVORABLE
TIMING OF THE WARM AIR ALOFT.
HIGH PRESSURE WILL BUILD IN THURSDAY AND FRIDAY...WITH COLD AIR
ADVECTION LIMITING TEMPS TO NEAR 30 ON THURSDAY...AND 20S ON FRIDAY.
FRIDAY NIGHT ANOTHER SYSTEM WILL MOVE ACROSS THE REGION...BUT
STRENGTH AND TIMING REMAIN UNCERTAIN. THE GFS IS FASTER AND STRONGER
THAN THE ECMWF/GEM...BUT NEITHER SOLUTION PRODUCES SIGNIFICANT
PRECIP...WHICH WILL BE ALL SNOW...ACROSS THE REGION. COLD AIR WILL
FUNNEL IN FOR THE EARLY PART OF NEXT WEEK...AND TO ECHO THE THOUGHTS
OF THE PREVIOUS FORECASTER...IT APPEARS MONDAY WILL HAVE HIGHS IN
THE SINGLE DIGITS...WITH LOWS BELOW ZERO OVERNIGHT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 554 PM CST MON JAN 26 2015
HIGH CONFIDENCE IN MVFR STRATUS REMAINING IN PLACE THROUGH THE
NIGHT ONCE IT ARRIVES...BUT WE DO NOT EXPECT PRECIP IN MINNESOTA
AND WHAT FALLS IN WISCONSIN SHOULD BE LIGHT AND SCATTERED IN
NATURE. WE DIDN`T INCLUDE ANY LIGHT SNOW OF FREEZING DRIZZLE AT
KEAU OR KRNH IN THE 00Z TAF...A BRIEF PERIOD OF PRECIP IS POSSIBLE
THIS EVENING BUT OVERALL THE WI SITES WILL JUST HAVE THE LOW
CLOUDS TO CONTEND WITH. SITES CURRENTLY SEEING CLOUD BASES BETWEEN
3000-4000FT EARLY THIS EVENING SHOULD EXPECT A LOWERING WITH TIME.
KMSP...
THERE IS A PRETTY GOOD CHANCE FOR CEILINGS RIGHT AROUND 2000FT FOR
THE TUESDAY MORNING COMMUTE...BUT WE ARE NOT VERY CONFIDENT IN
CEILINGS MUCH LOWER THAN THAT...SAY LOWER THAN 1700FT. NOT OUT OF
THE QUESTION THOUGH. KMSP SHOULD REMAIN PRECIP FREE OVER THE NEXT
24-36 HOURS.
/OUTLOOK FOR KMSP/
WED...VFR. CHC MVFR. WIND SE 10 KT.
THU...CHC MVFR/-SN. WIND NW 10-20 KT.
FRI...VFR. WIND VARIABLE 2-5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ015-
016-025>028.
&&
$$
SHORT TERM...SPD
LONG TERM...JRB
AVIATION...CLF
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
344 PM CST Sun Jan 25 2015
.SHORT TERM: (Through Late Tonight)
Issued at 323 PM CST Sun Jan 25 2015
Precip over the CWA should be winding down over the next few hours
as upper level impulse works its way SE into the Ohio Valley.
Deformation zone that was so well defined this morning over IA and
n IL certainly falling apart as the afternoon progresses, and have
used a combination of regional radar and HRRR for PoP/weather
trends heading into the early evening. It would appear that the NW
edge of the precip (now all snow) will be near a KCOU-KILX line
by 00z, with the precip dropping southeast and exiting
SE sections of the CWA no later than 06z. Surface obs trends this
afternoon indicate that rain begins mixing with snow @ 36-37 and
is all snow at 34 or colder, and will use this for ptypes for the
rest of the afternoon and into the early evening. Given warm
ground and the light intensity of the precip once it goes to all
snow, accumulations should continue to be very minor.
Other question for tonight is how much clearing will occur as the
storm exits and a narrow ridge of high pressure works into the
region. Over the last few hours have seen a wedge of clearing
wrapping around the surface low from S WI into NE IA. Some of this
clearing may reach our area, but there is also a lot of additional
low cloud to our north that will advect our way as well, so for
now have only gone with partial clearing during the late evening
and overnight hours.
Truett
.LONG TERM: (Monday through Next Sunday)
Issued at 323 PM CST Sun Jan 25 2015
(Monday-Wednesday)
Overall, going forecast heading into midweek still looks pretty
good, so this package will include generally minor adjustments and
tweaks to these trends.
Fast moving shortwave in northwest flow will zip into the region on
Monday, with WAA in advance of this feature rapidly shutting down
the CAA occuring overnight in the wake of today`s clipper. 12z
synoptic runs are suggesting a fairly strong N-S warm front will be
located near or just west of STL by late Monday afternoon and have
attempted to reflect this in max temp forecast, allowing highs to
rebound into the middle 50s over mid MO while keeping highs in the
30s over our S IL counties. This temp trend also seems to be
supported by the model RH progs which suggest a fairly thick mid
deck sweeping from W to E across the area in the zone of WAA during
the day, with the most clouds over our eastern counties during the
afternoon. Some 12z guidance is even trying to kick out some
light QPF near and east of the Mississippi River in the zone of
strongest WAA. Have continued dry forecast for now, but will need
to keep an eye on this as there has been some very subtle suggestions
of this for several days.
The cold air advection behind Monday`s shortwave will try to dip
into the area Monday night, but with the longwave trof working into
the east coast during this time the main thrust of this cooler air
will be east of our area. Model consensus of thermal profiles over
the region support highs in the 40s over most of the CWA by Tuesday
as weak surface ridge drops into the Mississippi Valley.
Warmup still appears to be on schedule for Wednesday, and main
question is how much of the warming will be able to translate to the
surface. Forecast soundings are suggesting a large inversion, with
low level mixing up to 900-950mb. Surface/low level winds...while
strong...are going to primarily be southerly rather than the
southwest direction that normally gives us our biggest warmups.
Also some doubt to how much cloud cover there will be, as GFS
suggests some mid clouds working into the area during the afternoon
while NAM suggests lots of sunshine. Due to the above uncertainty
will keep highs about where they are now...ranging from the mid 40s
in our far eastern counties to near 60 in the far western tip of our
CWA.
(Thursday-Sunday)
Shortwave that works across the region Wednesday night and early
Thursday appears to be the first of several chunks of energy that
will be deepening long wave trof over the eastern U.S. heading into
the weekend, while cutoff low forms over the southwestern U.S.
Medium range solutions are in very broad agreement in developing
this split flow pattern, and in general this should mean temps
trending back towards more wintry levels after the mid-week warmup.
Will continue some slight chance PoPs on Wednesday night/Thursday
for eastern parts of the FA in advance of aforementioned shortwave,
with slight chance PoPs also continuing for parts of the FA on
Saturday and Saturday night as there is agreement in the medium
range models that WAA, a bit of shortwave energy, and a frontal
boundary will be passing through the area at that time.
Guidance is in reasonable agreement with their thermal profiles
through Saturday, but much like yesterday the operational ECMWF
continues to be deepest with the upper trof and much colder than the
GFS by the end of the period (it`s intesting to note that last
nights ECMWF-based MOS had over a 40 degree difference between the
warm and cold members for Sunday`s highs (58 vs 16). For now, will
lean towards MOS averages for temp trends on Sunday...which will be
in the 30s. This seems to be a reasonable compromise at this point,
with additional adjustments occurring as specific trends become less
muddled.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1142 AM CST Sun Jan 25 2015
Low pressure centered just to the east-southeast of St. Louis will
continue moving east-southeast through tonight. Light rain falling
across much of the area will continue into the afternoon, changing
to light snow before ending early this evening. MVFR conditions
south of the I-70 corridor are expected to fall to IFR this
afternoon. IFR flight conditions are expected to continue to
prevail at least into the early evening, with improving ceilings
and visibilities as the precipitation comes to and end and the low
moves further east. Some guidance suggests that the low clouds
will scatter out overnight, however am siding with more pessimistic
models at this time as there is a lot of MVFR and even IFR up
across the Dakotas, Iowa, Minnesota, and Wisconsin. One other
feature of note, wind will be increasing substantially later this
afternoon as the low pulls away. Expect north-northwest wind
sustained between 15 to 20 kts with gusts potentially up to 30 kts.
Specifics for KSTL:
Expect IFR ceilings and at times IFR visibilities in light
rain/drizzle this afternoon. Wind will increase to the northwest
later sustained between 15 and 20 kts with gusts between 25 and
30 kts. Still expecting a little snow late this afternoon or early
this evening. Confidence in the exact timing of the snow is not
especially high though. Did not want to change the current 23Z
transition time for the 18Z TAF because of this, but an hour on
either side of 23Z still seems like the most likely. Snow should
end quickly this evening with ceilings between 1000-2000 FT
persisting through Monday morning.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1142 PM CST Sat Jan 24 2015
.UPDATE:
Issued at 1133 PM CST Sat Jan 24 2015
Updated lows as clouds and southwest winds have kept temperatures
from dropping as much. Lows to be in the mid 30s to mid 40s.
Byrd
Issued at 835 PM CST Sat Jan 24 2015
The radar was showing relatively weak reflectivities across
southwest IA, northeast KS, and into extreme northwest MO this
evening. Some of this light rain was evaporating before making it
to the ground due to an initially dry surface/boundary layer. This
rain was ahead of an approaching shortwave over southeast SD and a
weaker shortwave over eastern KS. This light rain should spread
into portions of northeast and central MO around midnight per the
latest HRRR model run. The latest NAM model run appears a little
deficient in its QPF tonight across MO. The light rain will spread
southeastward into much of the rest of our forecast area late
tonight/early Sunday morning as the main shortwave amplifies into
an upper level low and the surface low now over northwest IA and
southwest MN drops southeastward to just west of UIN by 12z
Sunday. Low temperatures tonight will be well above normal for
late January due to the lowering and thickening cloud cover along
with southwesterly surface winds for much of our area for most of
the remainder of tonight.
GKS
&&
.SHORT TERM: (Through Late Tonight)
Issued at 322 PM CST Sat Jan 24 2015
Elongated shortwave extending from Saskatchewan southeast into
Montana will dive southeast into Missouri by late tonight. The
associated low level circulation will drive southeast across Iowa
tonight and into extreme northeast Missouri by 12Z. All models are
printing out fairly widespread/light QPF ahead of the shortwave
along and north of the I-44 corridor from the Ozarks north to the
I-70 corridor. Another area of light QPF is showing up over
northern Missouri closer to the low level circulation. GFS and NAM
show a pretty broad area of 850-500mb omega ahead of the shortwave,
and a band of 850mb moisture convergence which sweeps through
Missouri into western Illinois ahead of the 850mb cold front. These
features appear to be the primary drivers for precipitation
tonight. 4KM ARW and NMM WRF members develop a broad area of
simulated reflectivity across the aforementioned parts of the CWFA
and MOS PoPs are likely to categorical in these areas as well.
Given all this, have increased PoPs from I-44 north to Quincy to
likely or better late tonight...with much of southwest Illinois east
of the STL Metro still staying in the high chance category. Kept
temperatures pretty mild in the mid 30s to near 40 with clouds and
southwest flow.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 322 PM CST Sat Jan 24 2015
(Sunday-Tuesday)
Over the last few days the synoptic guidance has been trending a bit
stronger/a bit more southwesterly with Sunday`s clipper system.
12z guidance has also followed this trend, with associated MOS also
indicating a sizeable jump in PoPs as well for the day on Sunday.
It would appear that band of rain that develops overnight will sweep
east into southern/eastern sections of the CWA early Sunday, along
and east of system`s cold front and in area of strong UVV with
initial shot of vorticity with upper system. This area of rain
will be followed by additional pockets of precip sprialling around
the upper low as it works into southern Illinois during the day.
While 850mb temps drop fairly quickly (model consensus indicates
0C isotherm will advect into southern sections of the CWA by
18z), forecast sounding from both NAM and GFS indicate cooling of
low level AMS and the drop of the freezing level to support snow
will be much slower than suggested by 850 mb temps alone. This
makes sense given the strong low level warming that should occur
ahead of the clipper later tonight and into early Sunday. Started
a changeover to snow in our far north by mid morning, with the
changeover dipping into the Ozarks in MO and to near the I70
corridor in IL by 00z Monday. Given how warm we are getting today
and the fact that it appears that the precip will be fairly light
once the changeover to snow occurs, it appears that any
accumulations will be quite minor...generally less than one-half
an inch and primarily near/east of the UIN area.
Precip in the form of light rain and light snow will wind down
across southeast sections of the CWA Sunday evening, with the quick
shot of cold air in the wake of the Clipper dropping temps into the
lower to middle 20s.
All of the 12z guidance indicates a very rapid rebound in temps on
Monday as the upper ridge over the Rockies begins to build into the
Plains. 30s will linger over our eastern counties but 40s seem
likely for areas along and west of the Mississippi...with some
locations in mid MO possibly pushing the 50 degree mark.
Shortwave partially driving Monday`s moderation will drop into the
east coast trof Monday night, with the CAA in the wake of the
shortwave allowing a weak cold front to drop into the mid
Mississippi Valley. However, greatest push of cold air will be well
east of our CWA, so Tuesday`s temps should be in the 40s over
most of the FA.
(Wednesday-Saturday)
Unseasonably warm airmass over the Plains should work its way east
at midweek as the UA pattern over the CONUS becomes progressive and
upper ridge works into the mid-Mississippi Valley. Given the
intensity of the warm air have gone a bit above initialization
numbers with a few locastion in mid MO pushing 60.
Next system in the increasingly active flow regime passes through
the area on Wednesday night. Cold air in the wake of the system
should return temps to more normal levels on Thursday, with temps
dropping a few more degrees on Friday.
While medium range solutions are in very good agreement into
Friday, they diverge considerably heading into the end of the
week. Both GFS and ECMWF develop a cut-off low over the southwestern
U.S. but mid level flow over the central CONUS varies considerably,
with GFS indicating a nearly zonal flow regime from the Rockies
into the east coast while the ECMWF suggests trof deepening over
the eastern half of the country...a much colder solution for our
area by next Saturday (ECMWF 850mb temps are about 10 degrees
colder than those of the GFS). For now have leaned towards the
warmer GFS, with a chance of rain or snow as broad overrunning is
progged across the region.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1133 PM CST Sat Jan 24 2015
Surface low over south central Iowa to continue tracking southeast
through forecast area during forecast period. Cigs to gradually
lower as system approaches with MVFR cigs/vsbys expected with
onset of main area of rain...between 11z and 14z Sunday. Will see
dry slot move into KCOU and metro area tafs by mid morning, so
kept vcsh mention. As for KUIN, they will remain mvfr and actually
lower to ifr as they are closer to track of surface low, lifting
back to mvfr by this evening. Then as colder air filters in this
afternoon, rain to pickup and become mixed with snow before coming
to an end this evening. Cigs to remain mvfr through rest of
forecast period. As for winds, southwest winds to veer to the west
then north and become gusty to around 25kts at times. North winds
to diminish by this evening but remain around 10 kts.
Specifics for KSTL:
Surface low over south central Iowa to continue tracking southeast
through forecast area during forecast period. Cigs to gradually
lower as system approaches with MVFR cigs/vsbys expected with
onset of main area of rain...by 14z Sunday. Will see
dry slot move into metro area tafs by 17z Sunday, so kept vcsh mention.
Then as colder air filters in this afternoon, rain to pickup and
become mixed with snow before coming to an end this evening. Cigs
to remain mvfr through rest of forecast period. As for winds,
southwest winds to veer to the west then north and become gusty to
around 25kts at times by 21z Sunday. North winds to diminish by this
evening but remain around 10 kts.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1137 PM CST Sat Jan 24 2015
.UPDATE...
Issued at 831 AM CST SAT JAN 24 2015
First round of rain is coming in a bit heavier than previously
thought and has been able to penetrate dry air at the surface. Still,
upstream observations indicate only one or two hundredths of an inch
of rain will fall from this activity, if that. Could see light rain
or sprinkles make it as far east as central MO later this evening.
Temperatures further upstream across Nebraska and the Dakotas are
warmer than many models had indicated. Near-term models such as the
RAP and HRRR seem to have a better grasp on this, so these were used
to update temperatures overnight and into Sunday morning which do not
appear as supportive of snow over northern MO. Still could see a few
flakes across these areas especially after 10 AM or so.
&&
.DISCUSSION...
Issued at 252 PM CST SAT JAN 24 2015
Tonight/Sunday...Confidence remains for chances of light
precipitation to overspread portions of the forecast area tonight
through Sunday. As of early this afternoon, water vapor imagery
showed a shortwave trough over eastern Montana into the western
Dakotas. This upper disturbance will rapidly drop southeastward,
reaching our forecast area by sunrise Sunday, and remain the
catalyst for the uptick in active weather during the next 24 hours.
Initial precipitation may develop in advance of strong PVA over east
central Kansas, sliding into west central Missouri before expanding
in coverage to the east. An additional area may also be initially
focused closer to the surface low pressure in northeast Missouri.
The initial coverage of precipitation prior to 09-12Z may be
somewhat spotty, with all precipitation falling in the form of rain,
per forecast soundings showing a notable warm layer several kft
above the surface. As the upper disturbance moves through with the
remaining area of deep ascent, a broader area of light precipitation
is expected to move through the region beginning Sunday morning. The
best chances will be across the northeast half of the CWA, with
decreasing chances with southwest extent. Upon the cold frontal
passage, colder air will advect into the area. Forecast soundings
show a cold/saturated enough profile to support snow or a mix of
rain/snow over portions of northern and northeastern Missouri during
the day on Sunday. Where snow can occur, considering light/meager
snow rates, relatively warm ground temperatures, and 2m air
temperatures above freezing, little to no accumulation is expected,
with any dusting reserved for grassy, insulated-type surfaces. All
precipitation is expected to exit from west to east by sunset Sunday.
The cooler weather on Sunday will be short-lived as the upper
pattern remains highly amplified, with a large ridge over the
Intermountain West Monday into Tuesday. Warm H85 temperatures on the
order of 10-13C will overspread much of the Central Plains Monday
through Wednesday, yielding afternoon high temperatures well above
seasonal levels for the region. The warmest day for the forecast
area should occur on Wednesday ahead of the next cold front as the
upper pattern begins to break down, with highs in the middle 50s to
lower 60s. Otherwise, cooler weather is expected to through the
remainder of the work week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1136 PM CST SAT JAN 24 2015
First round of rain moving through the region will taper off over the
next few hours. Ceilings and visibilities remain well into VFR so the
only significant impacts will be runway wetting. A lull is expected
later tonight followed by another round of lighter rain Sunday
morning, especially across northern and northeast MO. Could see a few
snowflakes Sunday afternoon toward IRK. Bigger concern will be winds
which could gust higher than 30kts at times Sunday morning.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...Hawblitzel
DISCUSSION...Blair
AVIATION...Hawblitzel
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1144 PM CST SAT JAN 24 2015
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 324 PM CST SAT JAN 24 2015
STRONG SHORTWAVE BRINGING COLDER TEMPERATURES AND A CHANCE FOR RAIN
AND SNOW THROUGH SUNDAY...THEN WARMER TEMPERATURES AGAIN TO START
THE WORK WEEK...REMAIN THE PRIMARY FORECAST CHALLENGES.
STRONG SHORTWAVE WAS NOTED ON WATER VAPOR IMAGERY DIVING THROUGH
EASTERN MONTANA THIS AFTERNOON. RAP ANALYSIS SHOWS 150KT 300MB JET
ACCOMPANYING SHORTWAVE. BOTH FEATURES WILL MOVE TOWARD OUR AREA
LATER THIS EVENING AND PROGRESS TO THE EAST ON SUNDAY. SCATTERED
SHOWERS WERE ALREADY OCCURRING IN WESTERN NEBRASKA CAUSED BY WEAK
VORTICITY LOBE AHEAD OF SHORTWAVE...WITH WING OF WARM ADVECTION
RAIN/SNOW EXTENDING FROM NORTH DAKOTA INTO EASTERN SOUTH DAKOTA
AHEAD OF MAIN SHORTWAVE. COULD SEE ISOLATED SHOWERS/SPRINKLES THIS
EVENING WITH WESTERN NEBRASKA ACTIVITY...BUT MAIN PRECIP CHANCE
WILL COME LATER THIS EVENING WITH NORTHERN PLAINS ACTIVITY. EXPECT
RAIN CHANCES TO INCREASE MARKEDLY BY MIDNIGHT ACROSS ALL OF
EASTERN NEBRASKA AND WESTERN IOWA...WITH LIKELY POPS IN OUR NORTH
WHERE LIFT ASSOCIATED BY MID LEVEL WARM ADVECTION IS MAXIMIZED.
FORECAST SOUNDINGS SUGGEST WARM SURFACE LAYER WILL KEEP PRECIP
LIQUID PAST MIDNIGHT BEFORE LOW LEVEL COLD ADVECTION KICKS
IN...CHANGING RAIN TO SNOW FROM NORTHWEST TO SOUTHEAST. BUT STILL
SURFACE AND BOUNDARY LAYER TEMPERATURES WILL BE SIGNIFICANTLY WARM
TO OFFER DOUBT WHETHER PRECIP WILL CHANGE TO ALL SNOW EXCEPT FOR
NORTHEAST NEBRASKA AND WEST CENTRAL IOWA. WHERE SNOW DOES
FALL...QPF LOOKS TO REMAIN UNDER A TENTH OF AN INCH WITH MELTING
OCCURRING AS WELL. THUS AMOUNTS OF A HALF INCH OR LESS ARE
FORECAST NORTH AND EAST OF THE OMAHA METRO AREA...WITH LITTLE
ACCUMULATION SOUTH AND WEST.
WINDS WILL ALSO KICK UP SIGNIFICANTLY OVERNIGHT...ESPECIALLY IN
NORTHEAST NEBRASKA. UNIDIRECTIONAL NORTHWESTERLY FLOW ACCOMPANIED
BY 50KT 850 JET...ALONG WITH LOW LEVEL INSTABILITY PROMOTING
MIXING OF BOUNDARY LAYER...SUGGEST WINDS OF 30 TO 45 MPH ARE
POSSIBLE BETWEEN MIDNIGHT AND MID SUNDAY MORNING. WILL ISSUE WIND
ADVISORY FOR PARTS OF OUR AREA TO COVER THIS.
PRECIPITATION SHOULD BE ENDING BY NOON SUNDAY...BUT STRONG COLD
ADVECTION WILL PERSIST DURING THE DAY. THUS TEMPERATURES WILL
PROBABLY REMAIN STEADY OF FALL MUCH OF THE DAY. HIGHS ONLY IN THE
30S ARE EXPECTED.
COOLDOWN BEHIND SYSTEM WILL BE BRIEF AS WINDS RETURN TO THE SOUTH OR
SOUTHWEST OVERNIGHT SUNDAY NIGHT AS ANOTHER SHORTWAVE MOVES ACROSS
THE NORTHERN PLAINS. TEMPS MAY RISE OVERNIGHT AFTER AN EVENING
LOW...THEN A WIND SHIFT BEHIND SURFACE TROUGH ASSOCIATED WITH
NORTHERN PLAINS SHORTWAVE WILL OCCUR EARLY MONDAY. GUSTY NORTHWEST
WINDS WILL PROMOTE DECENT MIXING MONDAY AFTERNOON WITH 850
TEMPERATURES IN THE 8-10C RANGE. HIGHS MONDAY AFTERNOON COULD REACH
60 IN OUR SOUTHWEST WITH PLENTY OF 50S ELSEWHERE.
A QUICK SHOT OF HIGH PRESSURE OVERHEAD TUESDAY MORNING WILL MOVE OFF
TO THE EAST...BRINGING SOUTHEASTERLY LOW LEVEL FLOW TUESDAY
AFTERNOON. THIS IS NORMALLY NOT A WARM WIND FOR US...SO TEMPS WILL
BE A GOOD 5 OR 10 DEGREES COOLER TUESDAY AFTERNOON DESPITE A SIMILAR-
TO-MONDAY LOW LEVEL TEMPERATURE PROFILE. STILL SHOULD SEE HIGHS IN
THE 50S MOST AREAS.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 324 PM CST SAT JAN 24 2015
ANOTHER WARM DAY WEDNESDAY WILL BE FOLLOWED BY COOLER TEMPERATURES
THROUGH THE END OF THE WEEK...AND LIKELY SIGNIFICANTLY COLDER BY
NEXT WEEKEND.
UPPER PATTERN WILL BECOME BRIEFLY ZONAL IN THE PLAINS ON WEDNESDAY
AS A PACIFIC SHORTWAVE APPROACHES FROM THE WEST. ANOTHER MILD DAY
WEDNESDAY IS FORECAST AHEAD OF THIS SHORTWAVE WITH SOUTH TO
SOUTHWEST FLOW PUMPING TEMPS BACK INTO THE 50S. SIGNIFICANT COOLING
IS EXPECTED BEHIND THIS WAVE WITH 850 TEMPERATURES DROPPING SOME 20C
BETWEEN WEDNESDAY AND THURSDAY AFTERNOONS. SOME LIGHT PRECIPITATION
IS POSSIBLE...BUT TRACK OF SURFACE LOW WILL BE WELL TO OUR
NORTHEAST. HIGH PRESSURE OVERHEAD THURSDAY WILL KEEP TEMPERATURES
FROM CLIMBING TOO FAR...WITH HIGHS STRUGGLING TO TOP 40. A LITTLE
WARMER FRIDAY AS SOUTH WINDS RETURN BRIEFLY AHEAD OF A STRONG COLD
FRONT DROPPING OUT OF THE NORTHERN PLAINS.
ECMWF AND GFS DIFFER GREATLY FOR FRIDAY NIGHT AND SATURDAY FORECAST.
GFS BRINGS A CLASSIC OVERRUNNING PATTERN TO THE PLAINS WITH
SIGNIFICANT SNOWFALL POSSIBLE. ECMWF KEEPS PRECIPITATION WELL SOUTH
OF OUR AREA AND SLAMS THE PLAINS WITH MINUS 20C 850 AIR. FOR NOW OUR
FORECAST WILL BLEND THESE TWO SCENARIOS WITH COLDER TEMPERATURES AND
A SMALL CHANCE FOR SNOW FRIDAY NIGHT AND SATURDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1140 PM CST SAT JAN 24 2015
LITTLE CHANGE FROM THE PREVIOUS FORECAST. EXPECT VERY WINDY
CONDITIONS THROUGH MID SUNDAY MORNING. CEILINGS ARE BEGINNING TO
FALL ACROSS THE AREA. FOR NOW HAVE MVFR CONDITIONS DOMINATING THIS
FORECAST BUT WOULDN/T BE SURPRISED TO SEE IFR CEILINGS FROM 10-14Z
AT OFK AND OMA. ALSO CAN/T RULE OUT A LIGHT RAIN/SNOW OVERNIGHT
BUT DON/T THINK THESE SHOULD LIMIT VISIBILITY MUCH. BUT THE MAIN
STORY SHOULD BE THE WIND AND LOW CEILING POTENTIAL.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 9 AM CST SUNDAY FOR NEZ011-012-015>018-
030>033-042>044-050-051-065-066-078.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...PEARSON
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
901 PM MST MON JAN 26 2015
.UPDATE...
UPPER LEVEL LOW ACROSS THE PACIFIC HAS RETROGRADED SO FAR WEST
THAT PRECIPITATION CHANCES FOR NM CONTINUE TO DWINDLE DESPITE ONE
LOBE OF ENERGY KICKING OUT ACROSS SOCAL. HRRR AGREES AND PRODUCES
LITTLE QPF ACROSS WESTERN NM AND NEW GUIDANCE FOR THE NAM SUGGEST
NONE. THUS HAVE RATCHETED DOWN POPS FOR TONIGHT...AND EVEN
THEN...THEY STILL MAY BE TOO HIGH. AMOUNTS LOOK TO BE LESS THAN A
TENTH OF AN INCH IF ANYONE DOES RECEIVE PRECIP. WITH THE SYSTEM SO
FAR WEST...THE EFFECTS SHOULD BE MINIMALIZED GOING INTO TOMORROW
AS WELL SO HAVE LOWERED POPS ONCE AGAIN FOR TUESDAY. HAVE ALSO
LOWERED OR REMOVED POPS FOR WEDNESDAY AND WEDNESDAY NIGHT AS WELL
AS ANY REMAINING EFFECTS FROM THIS STORM SYSTEM SHOULD LARGELY
REMAIN NORTH OF THE NM/CO BORDER AS IT ROUNDS THE RIDGE.
OTHERWISE...MINOR TWEAKS TO TONIGHTS TEMPS AND SKY COVER. UPDATES
ALREADY OUT.
34
&&
.PREV DISCUSSION...504 PM MST MON JAN 26 2015...
.AVIATION...
00Z TAF CYCLE
VFR CONDITIONS SHOULD BE MAINTAINED THROUGH THE NEXT 24 HOURS AT
ALL TERMINAL SITES. AN ISOLD SHRA OR HIGH MT SHSN WILL BE POSSIBLE
FROM THE CONTINENTAL DIVIDE TO THE AZ BORDER BETWEEN 06Z AND 18Z
TUESDAY. BRIEF MT OBSCURATIONS POSSIBLE. WILL ONLY CARRY VCSH IN
KGUP TAF FOR NOW.
&&
.PREV DISCUSSION...241 PM MST MON JAN 26 2015...
.SYNOPSIS...
A LARGE BUT SLOW MOVING STORM DRIFTING OUT OF THE EASTERN PACIFIC
COASTAL WATERS OF BAJA CALIFORNIA INTO THE GREAT BASIN THROUGH
TUESDAY WILL INTRODUCE SOME SHOWERS IN WESTERN NEW MEXICO THROUGH
TUESDAY. A MIDWEEK BREAK FROM WEATHER WILL COME TO AN END LATE
THURSDAY...AS THE NEXT TROPICAL PACIFIC OCEAN STORM DRIFTS INTO
THE DESERT SOUTHWEST. SLOW MOTION WILL PRODUCE LONGER PERIODS OF
RAIN AND HIGH COUNTRY SNOW THROUGH MUCH OF FRIDAY AND INTO THE
FOLLOWING WEEKEND. COLDER AIR SAGGING SOUTHWARD WILL MOVE SHOWER
COVERAGE TO SOUTHERN NEW MEXICO AS THE WEEKEND WINDS UP...WITH
SOUTHERN CLOUDS CONTRASTING WITH NORTHERN CLEARING AS THE WORK
WEEK GETS UNDERWAY IN THE FIRST DAYS OF FEBRUARY.
&&
.DISCUSSION...
CURRENTLY...RIDGE ALOFT EXTENDING FROM SOUTH TEXAS ACROSS NEW
MEXICO TO THE INLAND PACIFIC NORTHWEST RIGHT NOW...AS LARGE
PACIFIC STORM SYSTEM SITS OFF THE SOUTHERN CALIFORNIA COAST WELL
WEST OF NEW MEXICO...AND SPEEDY POLAR JET STREAM FROM WESTERN CANADA TO
THE GULF OF MEXICO COAST PROVIDING THE FEATURE TO THE EAST OF NEW
MEXICO. BROAD SURFACE DOME OF HIGH PRESSURE OVER NEW MEXICO WILL
REMAIN IN PLACE FOR RIGHT NOW.
MODELS...IN GOOD AGREEMENT THROUGH NEXT WEEKEND...AND A START ON
MONDAY. DIFFERENCES EMERGING LATE MONDAY ONWARD...AS EUROPEAN
COLLEAGUES AT ECMWF MOVE THEIR SYSTEM EASTWARD WITH
AUTHORITY...WHILE DOMESTIC GFS COLLEAGUES ARE MUCH SLOWER WITH
EASTWARD DRIFT OF SYSTEM ACROSS THE SOUTHWESTERN U.S. THROUGH
MIDWEEK OF THE FOLLOWING WEEK. GOOD START CONVERTS PACIFIC SYSTEM
CORE INTO A WAVE AND SHEARS THE WAVE ACROSS SOUTHERN CALIFORNIA
TONIGHT...AND ON INTO THE CENTRAL ROCKIES BY TUESDAY NIGHT. FLOW
OVER NEW MEXICO WILL SIMPLY VEER FROM SOUTHERLY TO WESTERLY BY
MIDWEEK...AS QUICK DISTURBANCE MOVING ACROSS THE CENTRAL ROCKIES
MIGHT TAG THE NORTHERN TIER OF NEW MEXICO ON WEDNESDAY NIGHT.
UPSTREAM...NEXT TROPICAL PACIFIC SYSTEM WILL DEEPEN OFF SOUTHERN
CALIFORNIA AND WESTERN BAJA CALIFORNIA...AND THIS TROUGH WILL
DRIFT AGONIZINGLY SLOWLY TO SOUTHERN CALIFORNIA THURSDAY
NIGHT...TO THE COLORADO VALLEY IN WESTERN ARIZONA FRIDAY...AND
THEN A WOBBLE INTO NORTHERN SONORA ON SATURDAY. STORM WILL PICK UP
STRONG POSITIVE TILT ON SUNDAY...WITH CORE REMAINING OVER
NORTHWESTERN MEXICO...AND THIS WILL CLOSE UP INTO A LOW OVER THE
SOUTHERN PORTIONS OF BAJA CALIFORNIA NEAR CABO SAN LUCAS AND LA
PAZ TO KICK OFF THE WORK WEEK. DIFFERENCES EMERGING INTO
TUESDAY...AS EUROPEAN SYSTEM WILL PICK UP EASTBOUND SPEED...REACH
TEXAS BY TUESDAY AND DROP STRONGER NORTHWEST FLOW INTO NEW MEXICO
BY WEDNESDAY. DOMESTIC GFS...ON THE OTHER HAND...WILL KEEP SYSTEM
POSITIVELY TILTED BUT MUCH SLOWER...WITH CORE OVER EASTERN NEW
MEXICO ON WEDNESDAY AND MUCH WEAKER NORTHWEST FLOW ALOFT OVER THE
REMAINDER OF THE STATE. DIFFERENCES FROM MONDAY NIGHT ONWARD ARE
SOMEWHAT MODEST...SO CAN SIMPLY SPLIT THE DIFFERENCE FOR NOW AND
KEEP AN EYE ON FUTURE RUNS FOR ANY NEEDED IMPROVEMENT ON RUN TO
RUN CONTINUITY FOR ONE VERSION OR THE OTHER.
OVERNIGHT...MILDER OVERNIGHT YET AGAIN...AS CLOUD COVER AND SOME
SHOWER COVERAGE WORKS NORTH ACROSS CATRON COUNTY AND ON TOWARD
INTERSTATE 40 FROM THE ARIZONA LINE TO THE CONTINENTAL DIVIDE.
MOST SPOTS WILL PICK UP ISOLATED TO SCATTERED RAIN SHOWERS...WITH
SOME OVERNIGHT CHANGE OVER TO SNOW OVER THE CHUSKA MOUNTAINS AND
SUMMITS SLOPES OF THE CONTINENTAL DIVIDE BY EARLY TUESDAY
MORNING. SNOW ACCUMULATION NOT EXPECTED TO BE MUCH IN THESE HIGHER
SPOTS. RIDGE AXIS WILL DRIFT EAST OVERNIGHT...AND END UP LYING FROM
TEXAS INTO THE NORTHERN ROCKIES ON THE EAST SIDE OF NEW MEXICO BY
TUESDAY MORNING. OVERNIGHT WINDS WILL RUN ON THE LIGHT SIDE.
FOR TUESDAY...FLOW OVER NEW MEXICO GOING FROM ZERO UNDER THE RIDGE
TO SOMEWHAT STAGNANT SOUTHWEST FLOW BY TUESDAY AFTERNOON...AS
NORTH BOUND TROUGH CLIPS THE FOUR CORNERS AND SHEARS OFF INTO
WESTERN COLORADO. SURFACE TROUGH FROM WEST KANSAS TO THE TEXAS
PANHANDLE WILL RETURN WEST TO SOUTHWEST FLOW ACROSS THE SURFACES
IN THE EAST...WITH SOME BREEZES GOING THROUGH THE SANGRE DE CRISTO
MOUNTAINS IN THE NORTH...AND ALONG INTERSTATE 40 IN THE EASTERN
SLOPES AND ADJACENT PLAINS OF THE CENTRAL MOUNTAIN CHAIN THROUGH
TUESDAY AFTERNOON. LAST OF THE WESTERN ISOLATED SHOWER COVERAGE
WITH HIGH COUNTRY SNOWFALL WILL MIGRATE TO THE NORTHERN TIER
TUESDAY NIGHT AS SURFACE TEMPERATURES REMAIN 8 TO 15 DEGREES ABOVE
LATE JANUARY NORMALS. SNOW ACCUMULATION WILL RUN ON THE LOW
SIDE...AND FOCUS ON THE SAN JUAN AND NORTHERN SANGRE DE CRISTO
SUMMITS...AND SOME CHANCE FOR A LITTLE SNOW OVER THE JEMEZ SUMMITS
BEFORE STORMS MOVE NORTH TUESDAY EVENING.
FOR WEDNESDAY...FLOW ALOFT PICKING UP SPEED AND VEERING FROM
SOUTHWEST TO WEST...AS QUICK SHORTWAVE MAKES QUICK TRIP EASTWARD
ACROSS SOUTHERN COLORADO THROUGH WEDNESDAY AFTERNOON. SURFACE LOW
DEEPENING OVER THE MISSOURI RIVER VALLEY AS HIGH PRESSURE SETS UP
OVER THE GREAT BASIN TO THE WEST WILL SUPPORT SOME NORTHWEST
BREEZES ACROSS NEW MEXICO...WITH BREEZY SPEEDS OVER THE SANGRE DE
CRISTO AND CENTRAL MOUNTAIN CHAIN SUMMITS...AND SETTING UP EASTERN
SLOPES AND ADJACENT PLAINS NORTHWEST BREEZES OVER THE INTERSTATE
40 CORRIDOR IN THE EAST. LAST OF THE ISOLATE SHOWER COVERAGE WILL
FLICKER OVER THE NORTHERN TIER NEAR THE COLORADO LINE THROUGH
WEDNESDAY NIGHT. MIDWEEK DAYTIME TEMPERATURES RUNNING
STEADY...WITH 8 TO 15 DEGREE WARM DEPARTURES ON TAP...WARMEST IN
THE EAST.
FOR THURSDAY...COLD FRONT OUT OF THE CENTRAL PLAINS STATES WILL
INVADE EASTERN NEW MEXICO DURING THE DAY...AND EXPAND RAPIDLY WEST
AND SOUTH TO THE CONTINENTAL DIVIDE BY LATE THURSDAY AFTERNOON
INTO THURSDAY NIGHT. ACTION WILL BRING TEMPERATURES OUT OF THE
WARMTH AND INTO CLIMATOLOGICAL CLOSENESS TO NORMAL FOR LATE
JANUARY...A FEW DEGREES COOL IN THE EAST. DAYTIME SHOWERS OVER THE
NORTHERN MOUNTAINS...AND BUILDING THE NEXT ROUND INTO THE SOUTHWEST
AND SOUTH CENTRAL MOUNTAINS...WILL BECOME BROAD AND WIDESPREAD
RAIN AND SNOW THURSDAY NIGHT AS THE SOUTHWEST BOUND COLD FRONT
COLLIDES RAPIDLY WITH EASTBOUND TROPICAL STORM SYSTEM WORKING INTO
NEW MEXICO. BREEZY EAST TO SOUTHEAST WINDS WILL SET UP OVER THE
SOUTHERN HALF OF THE STATE NEAR THE FRONT AND UNDER THE BEST
DYNAMICS OVERHEAD...AND THIS COULD SET UP SOME EASTERLY BREEZES
THROUGH THE CENTRAL MOUNTAIN CHAIN AND OUT OVER THE RIO GRANDE
VALLEY THROUGH THURSDAY AFTERNOON WITH THESE BREEZES CONTINUING
THROUGH THURSDAY NIGHT.
OUTLOOK...FRIDAY THROUGH THE WEEKEND...BIG COOL DOWN WILL PUSH
TEMPERATURES INTO DOUBLE DIGITS BELOW NORMAL BY SUNDAY...A TAD
LESS EXTREME IN THE WEST. STORM CORE OVER NEW MEXICO FRIDAY WILL
GRADUALLY WEAKEN COLD FRONT ON SATURDAY AS STORM REMAINS IN
PLACE AND CONTINUES TO KEEP WEATHER UNSETTLED...AND THEN AS NEXT
RAPIDLY SINKING COLD FRONT REINVIGORATES OVER EXTREME SOUTHERN NEW
MEXICO...STORM FOCUS WILL SHIFT TO THE SOUTHERN HALF OF THE STATE
THROUGH SUNDAY. FRIDAY AND SATURDAY WILL REMAIN BREEZY OVER THE
SOUTH WITH CONTINUING EAST TO SOUTHEAST WINDS...WITH WIND SPEEDS
DROPPING OFF ON SUNDAY AS DIRECTIONS SHIFT TO MORE NORTHERLY.
SHY
&&
.FIRE WEATHER...
NO CRITICAL FIRE WX CONDITIONS EXPECTED FOR AT LEAST THE NEXT WEEK.
ALSO LOOKING AT AN INCREASING POTENTIAL FOR A WIDESPREAD WETTING
PRECIP EVENT BETWEEN THU NIGHT AND SAT NIGHT ACROSS THE ENTIRE FCST
AREA.
OVERALL QUIET PATTERN TO CONTINUE INTO THU MORN...WITH FEW
EXCEPTIONS. POOR VENT RATES WILL STILL REMAIN THE CASE INTO TUE
AS WINDS ALOFT TO BE FAIRLY LIGHT AND SFC PRESSURE GRADIENT PRETTY
WEAK. TEMPS TO CONTINUE WELL ABOVE SEASONAL AVERAGES INTO WED
AREA WIDE. AN UPPER LOW WEST OF THE NORTHERN BAJA REGION WILL HEAD
INTO CALIFORNIA LATE TONIGHT AND THE GREAT BASIN TUE...BUT WEAKEN
SOME AS IT DOES SO. WHILE MOISTURE IS COMING INTO NM CURRENTLY AND
WILL CONTINUE TO DO SO INTO TUE...IT WILL WILL BE MORE IN THE MID
AND UPPER LEVELS AND LESS SO DOWN LOW. FCST MODELS CONTINUE TO TREND
LOWER WITH AMT OF PRECIP TO BE SQUEEZED OUT TONIGHT THROUGH WED
ACROSS THE WEST AND NORTH WITH LITTLE INDICATION OF ANY AMTS INTO
THE WETTING CATEGORY OF A TENTH OF AN INCH OR MORE DURING THIS
PERIOD. EXPECTED MAINLY ISOLATED LIGHT RAIN SHOWERS AND HIGHER MTN
SNOW SHOWERS MAINLY NEAR AND WEST OF THE DIVIDE.
WINDS SFC AND ALOFT TO INCREASE SIGNIFICANTLY TUE NIGHT AND WED
MOSTLY ACROSS THE NORTHERN MTNS AND EAST FROM THE CENTRAL MTN
CHAIN...BUT MINIMUM RH VALUES TO BE TOO HIGH FOR ANY CRITICAL FIRE
WX CONDITIONS TO DEVELOP...THOUGH SOME WIND GUSTS BETWEEN 35 AND 45
MPH ARE POSSIBLE THESE AREAS. SOME MODEST VENTILATION RATE
IMPROVEMENTS EXPECTED...MAINLY FROM NW AND SANDIA/MANZANO MTS OVER
THE CENTRAL HIGHLANDS AND FAR NORTHEAST. MOST OTHER LOCATIONS WILL
CONTINUE TO SEE POOR TO MARGINALLY FAIR RATES WED. THEREAFTER A
BACKDOOR COLD FRONT WILL PUSH INTO NM...BRINGING SOME COOLING AND A
PERIOD OF MOISTENING EAST TO WEST LOW LEVEL WINDS. GUSTY EASTERLY
WINDS INTO THE RIO GRANDE VALLEY APPEAR LIKELY TO DEVELOP BY LATE
WED NIGHT OR THU MORN AND PERSIST THROUGH THU NIGHT AND PERHAPS FRI.
ANOTHER SURGE OF COOLER AIR AT THE SURFACE COULD OCCUR BY FRI NIGHT
OR SAT. NEITHER OF THESE SURGES SHOULD BE TERRIBLY COLD...BUT WILL
DROP TEMPS SLIGHTLY TO MODERATELY BELOW NORMAL. AS MENTIONED BRIEFLY
AT START OF THIS DISCUSSION WE ARE LOOKING AT INCREASING POTENTIAL
FOR WIDESPREAD WETTING PRECIP OVER MUCH OF NORTHERN AND CENTRAL NM
STARTING THU NIGHT AND CONTINUING THROUGH SAT BEFORE TAPERING OFF.
SNOW LEVELS MAY DROP SOME AS THIS EVENT GOES ON...BUT STILL LOOKS
LIKE THEY WILL BE RANGING FROM ABOUT 3500 TO ABOUT 5500 FEET EAST
AND GENERALLY BETWEEN 6000 AND A LITTLE OVER 7500 WEST. VENT RATES
IMPROVE THU...DUE TO STRONGER TRANSPORT WINDS...BUT WORSEN AGAIN
FRIDAY...AND AGAIN PERHAPS IMPROVING MAINLY EAST SAT.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
34
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1006 PM EST MON JAN 26 2015
.SYNOPSIS...
LIGHT SNOW CONTINUES TO FALL THIS AFTERNOON ACROSS NEW YORK AND
PENNSYLVANIA, AN ADDITIONAL ONE TO THREE INCHES OF SNOW MALL FALL
THIS AFTERNOON. TONIGHT THE CLIPPER THAT BROUGHT SNOW SHOWERS TO
THE REGION WILL BECOME A POWERFUL NOR EASTER AND CREATE MANY
HAZARDOUS ACROSS MUCH OF THE NORTHEAST. HEAVY SNOW IS LIKELY OVER
THE POCONOS TO CATSKILLS THROUGH TUESDAY EVENING. A WINTRY
WEATHER PATTERN WILL PERSIST THROUGH THE WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
10 PM UPDATE...
LATEST HRRR IS KEEPING THE HEAVY SNOW BAND OUT OF PIKE/SULLIVAN
THROUGH THE OVERNIGHT HOURS, SO CONFIDENCE IN INTENSE SNOW IN THE
WARNING AREA OVERNIGHT IS DROPPING. SNOWFALL AMOUNTS FROM EARLIER
TURNED OUT TO BE HIGHER THAN EXPECTED DUE TO A HIGH SNOW TO H20
RATIO. MANY LOCATIONS HAVE REPORTED 3 TO 5 INCHES OF SNOW ALREADY,
SO WE MAY STILL REACH WARNING CRITERIA.
NO CHANGES TO FLAGS AT THIS TIME. WE HAVE LOWERED AMOUNTS SLIGHTLY
FOR THE OVERNIGHT HOURS.
425 PM UPDATE...
ISSUED A LAST SECOND WINTER WEATHER ADVISORY FOR PORTIONS OF
CENTRAL SO TIER AND FINGER LAKES. WE ARE RECEIVING REPORTS OF 3 TO
4 INCHES OF SNOW FROM TRAINED SPOTTERS IN THIS AREA, AND HRRR
HOLDS ACTIVITY OVER THE NEW ADVISORY AREA THROUGH THE EVENING. NEW
PROJECTIONS ARE FOR 3 TO 6 INCHES OVER THIS REGION.
330 PM EST UPDATE...
THE CALM BEFORE THE STORM...
LIGHT SNOW SHOWERS HAVE ADVANCED NORTHWARD THIS AFTERNOON AND NOW
HAVE REACHED PRETTY MUCH THE WHOLE CWA. THESE SHOWERS ARE EXPECTED
TO CONTINUE TO LIFT NORTHWARD THIS EVENING AND ADDITIONAL
ACCUMULATIONS OF 1 TO 3 INCHES OF SNOW ARE POSSIBLE... ESPECIALLY
OVER THE FINGER LAKE REGION.
TEMPS HAVE RISEN QUITE A BIT FROM THIS MORNING AND CURRENTLY RANGE
IN THE MID TEENS TO LOW 20S. TEMPS MAY INCREASE A COUPLE MORE
DEGREES THIS AFTERNOON THEN WILL SLOWLY DECREASE AFTER SUNSET.
THIS EVENING THE CLIPPER THAT HAVE BROUGHT THE CWA SNOW THIS
AFTERNOON WILL TRANSITION OVER TO A POWERFUL NOR`EASTER AND CREATE
COPIOUS AMOUNTS OF SNOWFALL FOR MUCH OF THE NORTHEAST. THIS
NOR`EASTER WILL BE DISCUSSED IN THE FOLLOWING SECTION.
&&
.SHORT TERM /TUESDAY NIGHT/...
330 PM EST UPDATE...
AS MENTIONED BEFORE THE CLIPPER WILL TRANSFORM INTO A POWERFUL
NOR`EASTER AND CREATE AN ALMOST STAND STILL FOR MUCH OF THE NEW
ENGLAND COAST. SNOW FROM THIS SYSTEM IS STILL EXPECTED TO START
AFTER 06Z TONIGHT AND MAY PREVAIL THROUGH THE LATE EVENING HOURS
ON TUESDAY. WE CONTINUE TO REMAIN ON THE FAR OUTER EDGE OF THIS
SYSTEM. WITH THAT BEING SAID... THERE ARE STILL SOME UNCERTAINTIES
WITH HOW MUCH SNOWFALL WILL FALL IN OUR CWA FROM THIS SYSTEM.
CONFIDENCE IS DECREASING THAT WE WILL REACH WARNING CRITERIA FOR
SULLIVAN AND PIKE COUNTY. ATTM IT APPEARS THAT THE GREATEST
MOISTURE AXIS WILL REMAIN WELL TO OUR EAST. ALSO... WITH EACH NEW
GUIDANCE RUN HINTING AT THAT EDGE SHIFTING EVER SO SLIGHTLY
EAST... WE MAY REACH ADVISORY AND NOT WARNING CRITERIA FOR THOSE
TWO COUNTIES. IT IS STILL TOO FAR OUT IN THE EVOLUTION OF THIS
STORM TO KNOW WHERE EXACTLY THE CUTOFF OF WARNING CRITERIA WILL
BE... THUS KEPT PREVIOUS WARNING/ADVISORY LOCATIONS THE SAME.
STORM TOTAL SNOWFALL ACCUMULATIONS WERE MODIFIED JUST SLIGHTLY
FROM THE PREVIOUS FORECAST. THE HIGHEST EXPECTED SNOWFALL
ACCUMULATIONS OVER THE CWA ARE STILL EXPECTED TO BE IN THE WESTERN
CATSKILLS AND THE POCONO MOUNTAIN REGION. ATTM... KEPT TEN TO
FOURTEEN INCHES TOTAL OVER THESE REGIONS. WE WILL CLOSELY MONITOR
THE OVERALL EVOLUTION OF THIS STORM AND UPDATE AS NECESSARY.
WINDS WILL BECOME GUSTY DURING THE DAY TOMORROW AND CREATE BLOWING
AND DRIFTING SNOW. WINDS ARE EXPECTED TO RANGE FROM 10 TO 20 MPH
WITH GUSTS UP TO 30. THIS WILL CREATE HAZARDOUS DRIVING
CONDITIONS.
TEMPS AFTER THIS SYSTEM PULLS AWAY WILL BE VERY COLD FALLING INTO
THE SINGLE DIGITS OR SLIGHTLY BELOW ZERO.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
220 PM UPDATE...
HIGH PRESSURE BUILDS IN QUICKLY BHND DEPARTING NOR`EASTER WITH CLDS
CLRNG DRG THE MRNG FM WEST TO EAST. H8 TEMPS WARM TO NR -10C
YIELDING HIGHS IN THE L/M 20S. S/WV RIDGING WORKS IN ALOFT WED NGT
WITH MOCLR SKIES THRU MOST OF THE OVRNGT BFR CLOUDING UP FM THE WEST
BY 12Z. DRY WX EXPECTED TO HOLD THRU THUR MRNG.
WARM ADVECTION WL OVRSPRD WRN ZONES THURSDAY MORNING BRINGING A LO
CHC OF LGT SNOW TO FINGER LKS AREA. UPR TROF AND ASSOC FRONTAL
SYSTEM SWINGS THRU THURSDAY NGT AND WITH ALL MODELS INDICATING THIS
SOLN HV OPTED TO GO LKLY POPS FOR SNOW BTWN 00Z AND 12Z FRIDAY. NW
FLOW WL CONTINUE BHND SYSTEM LEADING TO ANOTHER CHC FOR LK EFFECT
SNOW SHOWERS THRU FRI NGT UNTIL NEXT HIGH BUILDS IN.
BASICALLY FOLLOWED WPC GUIDANCE THRU THE END OF THE LONG TERM WITH
HIPRES RESULTING IN DRY WX THRU THE FIRST HALF OF THE WEEKEND. NEXT
CHC FOR SNOW SHOWERS APPEAR TO MV IN ON SUNDAY.
MODELS DIFFER SIGNIFICANTLY LATE IN THE LONG TERM WITH CLD CANADIAN
AIR FILTERING IN AS 12Z GFS HAS LOPRES OVR TOP OF CWA AS OPPOSED
TO EC INDICATING NRLY FLOW WITH HIPRES. THUS HV GONE WITH WPC
NUMBERS FOR LOWS NEXT MON MRNG WITH LOW TEMPS BLO ZERO.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
MAINLY LGT SNOWS OVER THE TAF SITES THIS EVENING WILL TEND TO
DIMINISH OVERNIGHT AS DRIER AIR MVES INTO THE AREA. IN GNRL...XPCT
MAINLY MVFR CIGS AND VSBYS INT HE LGT SNOW. LATE TNGT AND AFT
DAYBRK TUE...BAND OF HEAVIER SNOW ASSOCIATED WITH THE DEEPENING
CSTL STORM MAY PUSH BACK WWRD INTO THE AREA AND GIVE A PD OF LWR
CIGS AND VSBYS...WITH OCNL IFR CONDS PSBL. WITH THE DEEPENING
LOW...WINDS WILL TEND TO INCRS THRU THE PD OUT OF THE
NORTH...GUSTING WELL ABV 20 KTS ON TUE.
OUTLOOK...
TUE NGT-WED...LINGERING LAKE EFFECT -SHSN AND MVFR CIGS POSSIBLE
MAINLY NY TERMINALS INTO WED MORNING...OTHERWISE MAINLY VFR.
THU AND FRI...RESTRICTIONS FROM -SN.
SAT...BECOMING VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 PM EST TUESDAY FOR PAZ048.
WINTER WEATHER ADVISORY UNTIL 6 PM EST TUESDAY FOR PAZ040-072.
NY...WINTER STORM WARNING UNTIL 6 PM EST TUESDAY FOR NYZ062.
WINTER WEATHER ADVISORY UNTIL 6 PM EST TUESDAY FOR NYZ046-057.
WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR NYZ015-016-
022>024.
&&
$$
SYNOPSIS...KAH
NEAR TERM...DJP/KAH
SHORT TERM...KAH
LONG TERM...PVF
AVIATION...DGM/PVF
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1013 PM EST MON JAN 26 2015
.SYNOPSIS...
LOW PRESSURE OFF THE MID ATLANTIC COAST WILL DEEPEN RAPIDLY
AS IT LIFTS NORTHEAST AWAY FROM THE AREA TONIGHT AND TUESDAY.
HIGH PRESSURE WILL BUILD IN FROM THE WEST WEDNESDAY...THEN PASS
OFFSHORE THURSDAY. A COLD FRONT WILL MOVE THROUGH THE AREA
THURSDAY NIGHT INTO EARLY FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 1010 PM MONDAY...PATCHY LIGHT RAIN CONTINUES ACROSS THE
REGION...MAINLY ACROSS THE SOUTHWESTERN CWA. ADDITIONAL LIGHT
PRECIPITATION WILL APPROACH FROM THE DELMARVA/HAMPTON ROADS REGION
OVERNIGHT AND SHOULD ARRIVE AROUND TOWARD MORNING PER THE LATEST
3KM HRRR. COLD AIR SHOULD GRADUALLY ARRIVE IN EASTERN NC AFTER
MIDNIGHT WITH FREEZING LEVELS LOWERING TO UNDER 1000 FT BY 12Z
TUESDAY. ANY REMAINING PRECIPITATION WOULD BE ABLE TO MIX WITH
AND EVENTUALLY CHANGE TO SNOW ESPECIALLY OVER THE NORTHEAST
PORTION OF THE CWA PER THE HRRR MODEL. THIS IN COMBINATION WITH
SURFACE TEMPERATURES EXPECTED TO REMAIN ABOVE FREEZING AND
RELATIVELY WARM GROUND TEMPERATURES WILL PRECLUDE ANY SIGNIFICANT
ACCUMULATIONS AND IMPACTS.
LOW TEMPERATURES WILL FALL INTO THE 30S OVERNIGHT AND EXPECT MOST
AREAS WILL REMAIN ABOVE FREEZING THROUGH SUNRISE.
NO MAJOR CHANGES TO CURRENT FORECAST.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
STRONG VERT STACKED LOW WILL CONTINUE TO DEEPEN AND MOVE UP THE
EASTERN SEABOARD TUESDAY...WHILE DEEP UPPER TROUGH CONTINUES
ACROSS THE EAST COAST. MOISTURE WILL CONTINUE TO WRAP AROUND THE
SYSTEM TUESDAY...AND WHILE MOISTURE CONTINUES TO LOOK LIMITED
THERE WILL BE THE POTENTIAL FOR A BRIEF PERIOD OF WINTER WX.
THERMAL PROFILES AND CRITICAL THICKNESS VALUES INDICATE THE PRECIP
TRANSITIONING TO PRIMARILY LIGHT SNOW/SNOW SHOWERS TUESDAY MORNING
ACROSS EASTERN NC. TEMPS WILL GENERALLY REMAIN THE 30S TUE MORNING
AND ONLY WARMING TO AROUND 40/LOW 40S DURING THE AFTERNOON. WITH
SFC TEMPS ABOVE FREEZING MUCH OR ALL OF THE PERIOD...STILL EXPECT
MINIMAL IMPACTS WITH LITTLE TO NO SNOW ACCUMULATION. NW AREAS FROM
GREENVILLE AND WILLIAMSTON TO THE ALBEMARLE SOUND REGION AND THE
NRN OBX WILL HAVE THE BEST CHANCE TO SEE SOME LIGHT ACCUMULATION
AS THIS AREA WILL BE UNDER THE DEEPER WRAP AROUND MOISTURE THE
LONGEST...BUT WITH THE RELATIVELY WARMER ANTECEDENT CONDITIONS ANY
ACCUMULATION EXPECTED TO BE CONFINED PRIMARILY TO GRASSY AND
ELEVATED SURFACES. WITH LIGHT QPF AMOUNTS...NOT EXPECTING MORE
THAN A DUSTING AT ANY LOCATION. PRECIP WILL LIKELY TRANSITION BACK
TO A RAIN/SNOW MIX TUE AFTERNOON AS SFC TEMPS WARM TO AROUND 40.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
AS OF 345 PM MON...MOISTURE MOVES OFFSHORE TUE NIGHT AND WED
WITH DRY CONDITIONS AND MAINLY CLEAR SKIES. HIGH PRES BUILDS INTO
THE REGION WED AND WED NIGHT...THEN SHIFTS OFFSHORE THUR AS THE
NEXT CLIPPER SYSTEM APPROACHES FROM THE NORTHWEST. LOWS TUES NIGHT
AND WED NIGHT WILL BE IN THE MID 20S INLAND TO LOWER 30S ALONG THE
COAST. HIGHS WED AROUND 40-45 WITH ABOUT 5-7 DEGREES WARMING FOR
THU.
GAINING A LITTLE CONFIDENCE WITH A NRN STREAM CLIPPER SYSTEM TO
IMPACT THE REGION LATE WEEK AS THE GFS AND ECMWF STARTING TO
CONVERGE ON A SOLUTION. THE 12Z ECMWF HAS TRENDED DRIER AND NOT AS
STRONG WITH THE UPPER LEVEL SHORTWAVE. BOTH MODELS PRODUCING VERY
LIGHT QPF THURS NIGHT WITH LIMITED AVAILABLE MOISTURE. THERMAL
PROFILES SUPPORT ALL RAIN WITH ABOVE FREEZING TEMPS BELOW 850
MB. THE FRONT PUSHES OFFSHORE FRI MORNING. SHOWERS MAY LINGER
ALONG COASTAL SECTIONS IN THE MORNING BUT THE TREND WILL BE FOR
CLEARING SKIES THROUGH THE DAY AS ARCTIC HIGH PRES BUILDS IN FROM
THE NORTHWEST LATE FRI THROUGH SAT. HIGHS FRIDAY AROUND 40-45
BEFORE THE STRONG CAA COMMENCES BUT ONLY EXPECT UPPER 30S TO
LOWER 40S SATURDAY.
BELOW NORMAL CONFIDENCE CONTINUES LATE NEXT WEEKEND WITH THE
POTENTIAL FOR ANOTHER LOW TO DEVELOP ACROSS THE AREA. BOTH GFS AND
ECMWF HAVE TRENDED MUCH WETTER FOR LATE SUNDAY INTO EARLY
MONDAY...HOWEVER THERE REMAIN DIFFERENCES IN THE DETAILS WITH THE
UPPER LEVEL PATTERN AND ESPECIALLY THE SFC PATTERN...SPECIFICALLY
THE TRACK OF THE SFC LOW. THERE ARE IMPLICATIONS OF PTYPE CONCERNS
THE LOW TRACKS ALONG THE COAST OR OFFSHORE BUT AT THIS TIME
OPERATIONAL MODELS TRACK THE LOW ACROSS EASTERN NC (12Z ECMWF) OR
NORTH ACROSS THE MID ATLANTIC (12Z GFS).
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 00Z WEDNESDAY/...
AS OF 625 PM MONDAY...HIGH CONFIDENCE OF MVFR CONDITIONS THROUGH
THE NIGHT INTO EARLY AFTERNOON ON TUESDAY AS POTENT UPPER SYSTEM
DIVES ACROSS THE CAROLINAS PRODUCING LIGHT RAIN...BECOMING MIXED
WITH OR POSSIBLY CHANGING TO LIGHT SNOW LATE TONIGHT AND EARLY
TUESDAY MORNING. CONDITIONS SHOULD QUICKLY IMPROVE TUESDAY
AFTERNOON AS THE LOW QUICKLY EXITS TO THE NORTHEAST.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 345 PM MON...VFR CONDITIONS WILL PREVAIL THROUGH MUCH OF
THE LONG TERM. A CLIPPER SYSTEM WILL TRACK ACROSS THE AREA THURS
NIGHT BUT LITTLE MOISTURE IS EXPECTED WITH THIS SYSTEM AND VFR
EXPECTED TO DOMINATE BUT CANNOT RULE OUT A BRIEF PERIOD OF MVFR.
COLD HIGH PRES BUILDS INTO THE AREA LATE FRI AND SAT. COLD AIR
ADVECTION AND/OR A VERY DRY AIRMASS SHOULD PRECLUDE ANY SIGNIFICANT
FOG DEVELOPMENT.
&&
.MARINE...
SHORT TERM /THROUGH TUESDAY/...
AS OF 1010 PM MONDAY...WINDS CONTINUE TO RAMP UP ON THE COASTAL
WATERS AND SOUNDS WITH GUSTS TO 28 KNOTS AT DUCK COE PIER AND 25
KNOTS AT DIAMOND BUOY. SEAS HAVE FINALLY RESPONDED OVER THE PAST
COUPLE OF HOURS WITH 5 TO 7 FEET AT THE NORTHERN BUOYS. SMALL
CRAFT ADVISORIES WERE ISSUED EARLIER FOR ALL OF THE NEAR SHORE
WATERS/THE SOUNDS/AND THE ALLIGATOR RIVER. A BRIEF PERIOD MARGINAL
GALES ARE POSSIBLE OVER THE CENTRAL WATERS LATE TONIGHT INTO EARLY
TUESDAY. MILLER TYPE "B" CYCLOGENESIS OFF OF THE NC COAST DURING
THE NEXT 24 HOURS WILL LEAD TO HAZARDOUS WINDS AND SEAS DEVELOPING
TONIGHT. THIS EVENING THE FLOW WILL BECOME NORTHWEST AND INCREASE
TO 25 KT WITH HIGHER GUSTS AS RAPIDLY DEVELOPING LOW PRESSURE
MOVES UP THE EAST COAST LEADING TO BUILDING SEAS OF 6 TO 8 FT BY
EARLY TUESDAY MORNING. STRONG SMALL CRAFT ADVISORY CONDITIONS
CONTINUE THROUGH TUESDAY.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 345 PM MON...NNW WINDS WILL REMAIN STRONG...15-25KT GUSTS
30-35KT...THRU MIDWEEK AS LOW DEEPENS TO THE NORTHEAST AND
REINFORCES THE PRESSURE GRADIENT ALONG THE NC COAST. SCA
CONDITIONS EXPECTED TO CONTINUE THROUGH WEDNESDAY...THEN WINDS
WILL BEGIN TO DIMINISH WEDNESDAY NIGHT AND BACK TO THE W/SW
THURSDAY AS SFC HIGH PRESSURE SHIFTS OFFSHORE. THE POTENTIAL FOR
SCA CONDITIONS RETURN LATE THUR NIGHT AND FRI AS A COLD FRONT
MOVES THROUGH THE WATERS AND STRONG CAA DEVELOPING FRIDAY THROUGH
EARLY SATURDAY.
USED A BLEND OF WAVEWATCH AND LOCAL NWPS AS THE NWPS IS USUALLY
OVERDONE IN NW FLOW SITUATIONS. ELEVATED SEAS OF 6 TO 9 FT
EXPECTED TUE AND WED...HIGHEST CENTRAL AND NRN WATERS BEFORE
GRADUALLY SUBSIDING THRU THURSDAY. SEAS EXPECTED TO BUILD BACK TO
4-8 FT FRIDAY AND FRIDAY NIGHT...THEN GRADUALLY SUBSIDE THROUGH
THE DAY SATURDAY.
PERSISTENT GUSTY NNW FLOW...TONIGHT THROUGH WEDNESDAY...COULD
RESULT IN MINOR WATER LEVEL RISES FOR SOUND-SIDE AREAS OF THE
OUTER BANKS ADJACENT TO THE PAMLICO SOUND.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST WEDNESDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TUESDAY NIGHT FOR
AMZ130-131.
SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR AMZ150-152-
154.
SMALL CRAFT ADVISORY UNTIL 2 PM EST WEDNESDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...BTC
NEAR TERM...CTC
SHORT TERM...BTC
LONG TERM...SK/CQD
AVIATION...CTC/SK
MARINE...CTC/BTC/SK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1257 AM CST SUN JAN 25 2015
.UPDATE...
ISSUED AT 1257 AM CST SUN JAN 25 2015
AREAS OF PRECIPITATION PERSIST EARLY THIS MORNING ALONG TO EAST OF
AN INVERTED SFC TROUGH STRETCHING FROM EASTERN SOUTH DAKOTA BACK
NORTH-NORTHWEST ACROSS CENTRAL NORTH DAKOTA INTO SOUTHEASTERN
SASKATCHEWAN. EXPANDED POPS TO BETTER REFLECT LATEST RADAR IMAGERY
AND HIGH RES GUIDANCE (HRRR/NAM/RAP)...AND WILL MENTION SOME LOW
POPS 12-15Z SOUTH CENTRAL. PRECIPITATION WILL DIMINISH WITH TIME
THIS MORNING NORTH TO SOUTH AS THE SURFACE TROUGH WASHES OUT AND
FORCING ALOFT DECREASES.
LOW STRATUS CONTINUES TO PUSH SOUTH INTO THE REGION FROM SOUTH
CENTRAL CANADA. LATEST RAP/NAM MAINTAINS THE STRATUS DECK FOR MUCH
OF THE AREA THIS MORNING...THEN ERODES WEST TO EAST DURING THE
AFTERNOON AS OUR WINDS BECOME SOUTHWESTERLY. INCREASED SKY COVER A
BIT TO BETTER REFLECT LATEST MODEL OUTPUT INCLUDING THE
RAP/NAM/HRRR.
WAA TODAY WITH A FEW MODELS GENERATING LIGHT QPF ALONG THE WARM
FRONT. WHILE MOST AREAS LOOK TO REMAIN DRY...OPTED TO THROUGH IN A
SLIGHT CHANCE OF MAINLY LIGHT RAIN AS THE FRONT PUSHES EASTWARD
DURING THE AFTERNOON AND EARLY EVENING.
UPDATE ISSUED AT 931 PM CST SAT JAN 24 2015
AT 914 PM BISMARCK ASOS SURFACE OBS CHANGED TO RAIN FROM SNOW.
DUAL POLE PRODUCTS SUGGEST MIXED PRECIPITATION RAIN AND SNOW AS
THE CORRELATION COEFFICIENT FALLS BELOW 80 IN A NARROW BAND OVER
BISMARCK. ALTHOUGH RAIN...SEE THE VERY END OF THE PRECIPITATION
SHORTLY AS ITS ONLY A BAND ABOUT 10 MILES WIDE. FOR THIS FORECAST
WILL END THE PRECIPITATION SOONER ACROSS THE CENTRAL. WILL
CONTINUE LIGHT SNOW MOST OF THE NIGHT EAST.
UPDATE ISSUED AT 702 PM CST SAT JAN 24 2015
WIND ADVISORY HAS EXPIRED. EMPHASIZED THE EVENING LIGHT SNOW SOUTH
CENTRAL WITH DEFINITE POPS.
UPDATE ISSUED AT 548 PM CST SAT JAN 24 2015
RADAR SHOWS AN AREA OF LIGHT SNOW EXTENDING WEST OF BISMARCK.
BASED ON THIS AND LATEST HRRR RUNS WILL EXTEND THE LIKELY POPS FOR
SNOW WEST THROUGH MORTON COUNTY AND SOUTH TO THE SOUTH DAKOTA
BORDER. WILL LEAVE WIND ADVISORY GOING UNTIL 7 PM AS WINDS CONTINUE
TO GUST OVER 40 MPH AT SAND CREEK RAWS AND HETTINGER.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 245 PM CST SAT JAN 24 2015
AN UPPER LEVEL WAVE CONTINUES TO GENERATE AN AREA OF PRECIPITATION
EXTENDING OVER CENTRAL NORTH DAKOTA. THIS ACTIVITY WILL CONTINUE
TO PIVOT EAST THROUGH TONIGHT. WIND ADVISORY CONDITIONS WILL
CONTINUE OVER SOUTHWESTERN NORTH DAKOTA THROUGH THE REMAINDER OF
THE AFTERNOON AS WELL. THE MAIN FORECAST CHALLENGE WILL BE
DETERMINING THE PRECIPITATION TYPE FOR THE NEXT FEW HOURS.
A COOL CANADIAN AIR MASS CONTINUES TO NOSE INTO NORTH CENTRAL NORTH
DAKOTA THIS AFTERNOON. THIS HAS RESULTED IN ALL SNOW BEING REPORTED
OVER NORTH CENTRAL NORTH DAKOTA. HOWEVER...RELATIVELY WARMER
BOUNDARY LAYER AIR IS GENERATING A NARROW PATCH OF FREEZING RAIN
PRIMARILY OVER JAMESTOWN. AS THE CANADIAN AIR MASS NOSES SOUTH...THE
PRECIP TYPE SHOULD CONTINUE TO TRANSITION FROM RAIN/FREEZING RAIN TO
ALL SNOW OVER THE JAMES RIVER VALLEY BY THIS EVENING.
SNOW WILL LIKELY CONTINUE EAST OF HIGHWAY 83 TONIGHT. BY SUNDAY
MORNING...STORM TOTAL SNOW AMOUNTS SHOULD RANGE BETWEEN 1 AND 2
INCHES ALONG AND EAST OF A LINE FROM MINOT TO STEELE TO ELLENDALE.
AREAS WEST OF SAID LINE SHOULD RECEIVE LESS THAN AN INCH OF NEW SNOW.
LOW PRESSURE MOVING ACROSS SASKATCHEWAN WILL GENERATE DRY AND WARM
SOUTHWESTERLY FLOW OVER WESTERN AND CENTRAL NORTH DAKOTA SUNDAY. DRY
CONDITIONS AND ABOVE NORMAL TEMPERATURES ARE FORECAST. SUNDAY
AFTERNOON HIGHS SHOULD RANGE FROM THE 30S EAST TO THE UPPER 40S
SOUTHWEST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM CST SAT JAN 24 2015
...DRY WITH ABOVE NORMAL TEMPERATURES...
AN UPPER LEVEL RIDGE CURRENTLY OVER THE WEST COAST WILL SLOWLY
SHIFT EAST THROUGH THE NEXT COUPLE OF DAYS AND EVENTUALLY CENTER
ACROSS THE PLAINS TUESDAY. WITH PREDOMINATELY WEST WINDS THIS SETUP
WILL ALLOW FOR WELL ABOVE NORMAL TEMPERATURES THROUGH MIDWEEK.
ZONAL FLOW SHOULD THEN DEVELOP THURSDAY...WITH A TRANSITION TO
COOLER NORTHWEST FLOW BY THE WEEKEND. UPPER 40S ARE LIKELY ACROSS
MOST OF WESTERN AND CENTRAL NORTH DAKOTA MONDAY AND TUESDAY WITH
50S LIKELY ACROSS THE SOUTHWEST. BY THE WEEKEND ARCTIC AIR MAY
MAKE A RETURN TO THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1257 AM CST SUN JAN 25 2015
FAST MOVING LOW PRESSURE ACROSS THE EASTERN DAKOTAS WILL MOVE
SOUTHEAST TONIGHT. AN EXTENSIVE AREA OF MVFR TO IFR STRATUS WILL
REMAIN OVER THE STATE IN ITS WAKE. SNOW WITH OCCASIONAL IFR
CONDITIONS WILL PREVAIL FROM KMOT-KBIS-KJMS THROUGH 09-12Z THEN
SLOWLY IMPROVE BUT MVFR STRATUS WITH POCKETS OF IFR WILL PERSIST
THROUGH THE MORNING. CONDITIONS IMPROVE WEST TO EAST DURING THE
AFTERNOON...WITH LATEST MODELS NOW INDICATING ANOTHER LOW STRATUS
FIELD MOVING INTO WESTERN NORTH DAKOTA LATE SUNDAY INTO SUNDAY
EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...TM
LONG TERM...AJ
AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1132 PM CST SAT JAN 24 2015
.UPDATE...
ISSUED AT 1133 PM CST SAT JAN 24 2015
CURRENT RADAR SHOWS BEST REFLECTIVITIES ALONG ROUGHLY A BOTTINEAU
TO RUGBY TO HARVEY TO STEELE LINE...WITH LESSER RETURNS OVER MOST
OF SOUTHEASTERN ND. WE ARE GETTING GROUND TRUTH IN THE SOUTHWEST
BUT NORTHERN VALLEY ECHOES ARE CLOUDS ONLY...AS NORTHEAST FLOW IS
KEEPING BNDRY LYR DRY. 02Z RUC NICELY DEPICTS THE EASTWARD EXTENT
OF THE SNOW...WHICH IS BEING HAMPERED BY THE NE FLOW. HAVE UPDATED
POPS WITH RUC GUIDANCE AND MADE SOME ADJUSTMENTS IN THE SRN
VALLEY...WHERE RUC WAS A BIT LOW WITH POPS. CONTINUE TO EXPECT
MOST OF NORTHEASTERN QUARTER OF CWA TO RECEIVE LITTLE IF NO
SNOWFALL TONIGHT...AND ONE TO TWO INCHES IN PORTIONS OF EAST
CNTRL AND SOUTHEASTERN ND.
UPDATE ISSUED AT 655 PM CST SAT JAN 24 2015
CURRENT FORECAST LOOKS ON TRACK...LIGHT SNOW FALLING OVER WEST
CENTRAL AND SOUTHWESTERN PORTIONS OF CWA...WITH SOME OBS OF RAIN
IN CNTRL ND EARLIER ON...WHICH HAS NOW CHANGED TO SNOW. MAIN
ISSUE TO WATCH TONIGHT IS EASTWARD EXTENT OF SNOW...AS CURRENT POP
GRIDS KEEP LIKELIES JUST WEST OF GRAND FORKS AND DO BRING IT IN TO
THE FARGO AREA. WILL HOLD OFF ON ANY ADJUSTMENTS UNTIL 00Z NAM
COMES IN AS FCST IN PRETTY GOOD SHAPE RIGHT NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 253 PM CST SAT JAN 24 2015
MAIN FORECAST CHALLENGE WILL BE THE BAND OF PCPN MOVING THROUGH
THE AREA LATE THIS AFTERNOON/TONIGHT. 12Z MODEL RUNS CONTINUED TO
PUSH BACK WESTWARD WHERE THIS BAND WILL FALL AND IT APPEARS THAT
SOME OF THE 18Z GUIDANCE MAY BE EVEN LIGHTER WITH THE EXPECTED
AMOUNTS. AS OF MID AFTERNOON MOST OF THE LIGHT PCPN WAS FALLING
BETWEEN KMOT AND KJMS AND WAS SLIDING SE. SOME OF THIS LIGHT PCPN
DID EXTEND INTO THE FAR WESTERN FA. LOOKING AT SFC TEMPS...THEY
WERE 30F AT KDVL AND 32F AT KJMS AND 37F AT GWINNER. SFC OBS WERE
REPORTING LIGHT SNOW AT CARRINGTON AND FZDZ/LIGHT SNOW AT KJMS
WITH THE WARMEST SFC AIR AT GWINNER (ALTHOUGH NO PCPN YET). WITH
THE CONTINUED COOL ADVECTION LATE THIS AFTERNOON AND TONIGHT ANY
MIX ACROSS THE SW FA WILL BE BRIEF. 18Z NAM COMING IN EVEN WEAKER
WITH EXPECTED SNOW AMOUNTS...WITH LESS THAN INCH ACROSS THE WEST
AND A DUSTING CLOSER TO THE RED RIVER VALLEY. ALL SAID THIS EVENT
IS MUCH WEAKER AND FURTHER WEST THAN EXPECTED. WILL KEEP SOME
MINIMAL CHANCES FOR LIGHT SNOW ACROSS MAINLY THE SOUTH ON SUNDAY
MORNING BEFORE THE SYSTEM EXITS OFF TO THE SE. ANOTHER WEAK LIGHT
SNOW PRODUCING SYSTEM WILL AFFECT THE NORTHEAST FA BEGINNING SUN
NIGHT. AS THE SFC LOW PASSES TO THE NORTH AND EAST...PRETTY DECENT
WARMING OCCURS AGAIN. THEREFORE COULD EASILY SEE RISING TEMPS
SUNDAY NIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 253 PM CST SAT JAN 24 2015
WILL LINGER THE LIGHT SNOW CHANCES IN THE NORTHEAST FA ON MONDAY.
WEST TO NW WINDS CONTINUE ON MONDAY WITH VERY MILD AIR MOVING BACK
IN. KEPT HIGHS ON MONDAY ABOVE GUIDANCE TEMPS. STAYS QUIET MON
NIGHT INTO TUE. MUCH LIGHTER SFC WINDS ON TUE MAY KEEP TEMPS DOWN
A LITTLE BUT MORE LIKELY WILL DEPEND ON CLOUD COVER. EITHER WAY
WILL STICK WITH MILD TEMPS INTO TUE.
FOR TUE NIGHT THROUGH SAT...THE BEGINNING OF THE EXTENDED WILL START
OUT WARM WITH TEMPS ABOVE NORMAL. THERE COULD BE SOME LIGHT SNOW WED
NIGHT BEHIND A COOL FRONT...THEN AGAIN TOWARDS THE END OF NEXT WEEK.
A MORE SIGNIFICANT COLD FRONT IS PROGGED BY NEXT SAT...THAT COULD
MEAN AN END TO THE MILD TEMPS WE HAVE SEEN RECENTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1133 PM CST SAT JAN 24 2015
NORTHEAST FLOW SET UP AT DVL AND CIGS HAVE RISEN INTO UPPER MVFR
RANGE...WITH ALL OTHER SITES IN THE VALLEY AND NORTHWEST MN VFR.
WILL LIKELY SEE SOME FLURRIES OR LIGHT SNOW AT DVL...MORE LIKELY
AT FAR...THAT COULD BRING VSBYS INTO THE 3 SM TO 5 SM RANGE. OTHER
THAN THAT...LOW VFR DECK WILL PERSIST THROUGH EARLY SUN AFTN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...GODON
LONG TERM...GODON/DK
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1006 PM CST SAT JAN 24 2015
.UPDATE...
ISSUED AT 1006 PM CST SAT JAN 24 2015
CURRENT RADAR SHOWS BEST REFLECTIVITIES ALONG ROUGHLY A BOTTINEAU
TO RUGBY TO HARVEY TO STEELE LINE...WITH LESSER RETURNS OVER MOST
OF SOUTHEASTERN ND. WE ARE GETTING GROUND TRUTH IN THE SOUTHWEST
BUT NORTHERN VALLEY ECHOES ARE CLOUDS ONLY...AS NORTHEAST FLOW IS
KEEPING BNDRY LYR DRY. 02Z RUC NICELY DEPICTS THE EASTWARD EXTENT
OF THE SNOW...WHICH IS BEING HAMPERED BY THE NE FLOW. HAVE UPDATED
POPS WITH RUC GUIDANCE AND MADE SOME ADJUSTMENTS IN THE SRN
VALLEY...WHERE RUC WAS A BIT LOW WITH POPS. CONTINUE TO EXPECT
MOST OF NORTHEASTERN QUARTER OF CWA TO RECEIVE LITTLE IF NO
SNOWFALL TONIGHT...AND ONE TO TWO INCHES IN PORTIONS OF EAST
CNTRL AND SOUTHEASTERN ND.
UPDATE ISSUED AT 655 PM CST SAT JAN 24 2015
CURRENT FORECAST LOOKS ON TRACK...LIGHT SNOW FALLING OVER WEST
CENTRAL AND SOUTHWESTERN PORTIONS OF CWA...WITH SOME OBS OF RAIN
IN CNTRL ND EARLIER ON...WHICH HAS NOW CHANGED TO SNOW. MAIN
ISSUE TO WATCH TONIGHT IS EASTWARD EXTENT OF SNOW...AS CURRENT POP
GRIDS KEEP LIKELIES JUST WEST OF GRAND FORKS AND DO BRING IT IN TO
THE FARGO AREA. WILL HOLD OFF ON ANY ADJUSTMENTS UNTIL 00Z NAM
COMES IN AS FCST IN PRETTY GOOD SHAPE RIGHT NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 253 PM CST SAT JAN 24 2015
MAIN FORECAST CHALLENGE WILL BE THE BAND OF PCPN MOVING THROUGH
THE AREA LATE THIS AFTERNOON/TONIGHT. 12Z MODEL RUNS CONTINUED TO
PUSH BACK WESTWARD WHERE THIS BAND WILL FALL AND IT APPEARS THAT
SOME OF THE 18Z GUIDANCE MAY BE EVEN LIGHTER WITH THE EXPECTED
AMOUNTS. AS OF MID AFTERNOON MOST OF THE LIGHT PCPN WAS FALLING
BETWEEN KMOT AND KJMS AND WAS SLIDING SE. SOME OF THIS LIGHT PCPN
DID EXTEND INTO THE FAR WESTERN FA. LOOKING AT SFC TEMPS...THEY
WERE 30F AT KDVL AND 32F AT KJMS AND 37F AT GWINNER. SFC OBS WERE
REPORTING LIGHT SNOW AT CARRINGTON AND FZDZ/LIGHT SNOW AT KJMS
WITH THE WARMEST SFC AIR AT GWINNER (ALTHOUGH NO PCPN YET). WITH
THE CONTINUED COOL ADVECTION LATE THIS AFTERNOON AND TONIGHT ANY
MIX ACROSS THE SW FA WILL BE BRIEF. 18Z NAM COMING IN EVEN WEAKER
WITH EXPECTED SNOW AMOUNTS...WITH LESS THAN INCH ACROSS THE WEST
AND A DUSTING CLOSER TO THE RED RIVER VALLEY. ALL SAID THIS EVENT
IS MUCH WEAKER AND FURTHER WEST THAN EXPECTED. WILL KEEP SOME
MINIMAL CHANCES FOR LIGHT SNOW ACROSS MAINLY THE SOUTH ON SUNDAY
MORNING BEFORE THE SYSTEM EXITS OFF TO THE SE. ANOTHER WEAK LIGHT
SNOW PRODUCING SYSTEM WILL AFFECT THE NORTHEAST FA BEGINNING SUN
NIGHT. AS THE SFC LOW PASSES TO THE NORTH AND EAST...PRETTY DECENT
WARMING OCCURS AGAIN. THEREFORE COULD EASILY SEE RISING TEMPS
SUNDAY NIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 253 PM CST SAT JAN 24 2015
WILL LINGER THE LIGHT SNOW CHANCES IN THE NORTHEAST FA ON MONDAY.
WEST TO NW WINDS CONTINUE ON MONDAY WITH VERY MILD AIR MOVING BACK
IN. KEPT HIGHS ON MONDAY ABOVE GUIDANCE TEMPS. STAYS QUIET MON
NIGHT INTO TUE. MUCH LIGHTER SFC WINDS ON TUE MAY KEEP TEMPS DOWN
A LITTLE BUT MORE LIKELY WILL DEPEND ON CLOUD COVER. EITHER WAY
WILL STICK WITH MILD TEMPS INTO TUE.
FOR TUE NIGHT THROUGH SAT...THE BEGINNING OF THE EXTENDED WILL START
OUT WARM WITH TEMPS ABOVE NORMAL. THERE COULD BE SOME LIGHT SNOW WED
NIGHT BEHIND A COOL FRONT...THEN AGAIN TOWARDS THE END OF NEXT WEEK.
A MORE SIGNIFICANT COLD FRONT IS PROGGED BY NEXT SAT...THAT COULD
MEAN AN END TO THE MILD TEMPS WE HAVE SEEN RECENTLY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 655 PM CST SAT JAN 24 2015
NORTHEAST FLOW WILL HELP KEEP CIGS MVFR AT BJI AND TVF...AND
EVENTUALLY GFK. MAIN ISSUE WILL BE MVFR CIGS...INTERMITTENTLY
IFR...WITH LIGHT SNOW OVER FAR/DVL TONIGHT. CLIPPER SYSTEM WILL
MOVE INTO MO BY 12Z AND MOST PRECIP ON NORTH EDGE SHOULD CLEAR THE
SRN RRV BY MID MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...GODON
LONG TERM...GODON/DK
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
652 PM EST MON JAN 26 2015
.SYNOPSIS...
PERIODS OF LIGHT SNOW WILL DECREASE ACROSS CENTRAL PENNSYLVANIA
TONIGHT AS A STRONG COASTAL STORM TRACKS TOWARDS NEW ENGLAND
TONIGHT. THE COASTAL STORM WILL RAPIDLY INTENSIFY TONIGHT AND
TUESDAY...AS IT TRACKS EAST OF NEW ENGLAND. HIGH PRESSURE WILL
BUILD OVER THE REGION FOR THE MIDDLE OF THE WEEK...FOLLOWED BY AN
ALBERTA CLIPPER THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
600 PM UPDATE...
EXTENDED THE ADVY FOR THOSE MIDDLE SUSQ COUNTIES THRU 11 PM...AS
SNOW IS STILL FALLING AND IS NOT TAPERING OFF AS QUICKLY AS 4KM
NAM/RAP/HRRR HAD PORTRAYED. MDLS CONTINUE TO INDICATE THAT THIS IS
THE FIRST AREA OF THE CWA WHICH WILL HAVE THE SNOW DROP TO
NOTHING. SNOW HAS RE-ENTERED/DEVELOPED OVER THE SE AND CURRENT
NUMBERS STILL LOOK GOOD OVER THE WHOLE REGION.
PREV...
ADDED TIOGA CO TO THE ADVY AS SNOW SHOULD CONTINUE TO FALL THERE
FOR ANOTHER FEW HRS AND THEY ARE ALREADY PUSHING 3-5 INCHES OF
SNOW OFF THEIR CARS. HOWEVER...THE RAP AND HRRR BOTH SLIDE THE BIG
BAND OFF TO THE WEST /NOT EAST/ SLIGHTLY - SO LESSER CHANCE FOR
SULLIVAN CO PA TO GET TOO MUCH MORE. JUST UPPED POPS SLIGHTLY TO
JUST BELOW 101 PERCENT IN THE CENTRAL AND WEST.
PREV...
DEFORMATION BETWEEN THE INVERTED SFC TROF OVER WESTERN AND
SOUTHWESTERN PA AND RAPIDLY DEVELOPING COASTAL LOW OFF OF
SOUTHEAST VA IS MAINTAINING CATEGORICAL POPS/SNOW ACROSS THE
LAURELS AND CENTRAL/WEST CENTRAL/NORTHWEST/NORTHERN MOUNTAINS
PRESENTLY. MY SOUTHEAST COUNTIES HAVE STARTED TO SEE SOME LIGHT
ACTIVITY BUT IT IS STILL REMOVED FROM THE BETTER DEFORMATION
ASSOCIATED WITH THE INVERTED TROF TO THE WEST AND THE INTENSIFYING
LOW TO THE EAST. LOWERED THE LOWER END OF SNOW FAR RANGES FOR THE
EAST IN WSW...GENERALLY 2 TO 5 INCHES EXPECTED OVERALL BEFORE
ACCUM SNOWFALL EXITS PA BY DAYBREAK TUE MORNING.
OVERALL HOWEVER...WIDESPREAD LIGHT SNOW WILL CONTINUE TO FALL OVR
CENTRAL PA THIS EVENING INTO LATE TONIGHT ALONG THE AXIS OF DEEP
EASTERLY FLOW BTWN LOW TO THE SOUTH AND HIGH PRES OVR NEW
ENGLAND...FORCED LOCALLY BY THE INCREASING AFOREMENTIONED
DEFORMATION. HI RES NAM/HRRR/WRF ARW ALL SUPPORT AN ADDITIONAL 1-3
INCHES TODAY...WITH THE HIGHEST AMTS ACROSS THE CENTRAL
MTNS/ALLEGHENIES. KEEPING HEADLINES AS IS FOR NOW BUT SOME MAY
NEED TO BE EXTENDED OVERNIGHT DEPENDING UPON WHERE THE DEFORMATION
PROPOGATES. HRRR INDICATES A SOUTHWEST SHIFT TO THE FORCING AFTER
03Z...AS THE PARENT COASTAL CIRCULATION DOMINATES AND TAKES OVER
EFFECTIVELY DISRUPTING AND ELIMINATING THE DEFORMATION FORCING
SNOWFALL OVER CENTRAL PA BY 12Z.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
AS MENTIONED ABOVE...DEFORMATION SNOW SHOWERS SHOULD DWINDLE EARLY
TUESDAY...WHILE NNW FLOW IN WAKE OF DEPARTING COASTAL LOW DRAWS
MUCH DRIER AIR INTO CENTRAL PA. 25 TO 35KT NE WIND GUSTS WILL BE
FELT AS TIGHT PRES GRADIENT IS REALIZED IN WAKE OF STORM JUST
OFFSHORE OF SOUTHERN NEW ENGLAND COAST. AS PREVIOUSLY
MENTIONED...THERE IS THE POTENTIAL OF SOME BLOWING/DRIFTING...ESP
EASTERN PA WHERE BUKFIT SOUNDINGS SUPPORT GUSTS BTWN 30-35KTS. ENS
MEAN 925 TEMPS SUPPORT MAX TEMPS TUE FROM NR 20F OVR THE N
MTNS...TO ARND 32F ACROSS THE LOWER SUSQ VALLEY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
DEEP STORM WILL PULL AWAY FROM PA TUESDAY NIGHT. WITH WINDS
FROM THE NORTH...TOOK OUT SNOW SHOWERS FOR JST.
SKIES SHOULD CLEAR OUT BY WED MORNING.
MAIN CHANGE WAS WED NIGHT...DID LOWER TEMPS...BASED ON 12Z
MODEL RUNS...AND THAT WITH MAINLY CLEAR SKIES AND LIGHT
WINDS...EXPECT TEMPS TO DROP...WITH FRESH SNOW COVER.
NEXT SYSTEM WILL BRING SOME SNOW SHOWERS TO THE AREA LATER THU
INTO FRIDAY. THIS SYSTEM NOT LOOKING LIKE IT WOULD RESULT IN
A COASTAL REAL NEAR THE COAST.
COLDER AIR FOR FRIDAY NIGHT.
WEEKEND NOT LOOKING TOO BAD...COLDER AIR WILL TRY TO BUILD IN
EARLY NEXT WEEK.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
FOR 00Z PACKAGE...EXTENDED POOR CONDITIONS FURTHER OUT IN
TIME.
WHILE CONDITIONS MAY NOT BE BAD ALL THE TIME...AS BEEN THE
CASE SINCE I CAME IN AT 8 AM THIS MORNING...DEEP STORM
FORMING JUST OFF THE MID ATLANTIC COAST AT THIS TIME WILL
CONTINUE TO WRAP MOISTURE TO THE WEST. RADAR SHOWS RATHER
HEAVY SNOW NOW TO THE WEST AND SW OF MDT...EXTENDING
NORTHWARD TO BETWEEN UNV AND IPT. SW WINDS AT IPT SUGGEST
INVERTED TROUGH STILL IN PLACE. SNOW WILL BE AN PROBLEM
UNTIL THIS FEATURE FALLS APART ON TUE.
WINDS WILL PICK UP ON TUESDAY...AS STORM STARTS TO PULL
NORTH ADN EAST OF THE AREA.
OUTLOOK...
WED...VFR WITH NO SIG WEATHER EXPECTED.
THU...VFR TO START...WITH LATE DAY RESTRICTIONS SPREADING IN FROM
THE WEST.
THU NIGHT-FRI...WIDESPREAD IFR/MVFR IN SNOW.
SAT...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR PAZ004>006-
010>012-017>019-024>026-033>036-045-058-059-064>066.
WINTER WEATHER ADVISORY UNTIL 11 PM EST THIS EVENING FOR
PAZ027-028-037-041-046-049>053-056-057-063.
&&
$$
SYNOPSIS...DEVOIR/FITZGERALD
NEAR TERM...DANGELO/DEVOIR/FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...MARTIN
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1244 AM EST SUN JAN 25 2015
.SYNOPSIS...
AN ALBERTA CLIPPER WILL TRACK JUST SOUTH OF PENNSYLVANIA SUNDAY
NIGHT WITH ANOTHER WEAKER CLIPPER TAKING THE SAME PATH MONDAY
NIGHT AND EARLY TUESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION
MID WEEK...FOLLOWED BY ANOTHER CLIPPER LATE THURSDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
HAVE CANCELLED THE FREEZING RAIN ADVISORY FROM CLEARFIELD CO
NORTHWARD...WHERE ARRIVAL OF DEEPER MOISTURE HAS CHANGED PRECIP TO
-SHSN. HOWEVER...LATEST NAM AND RAP SOUNDINGS INDICATE CLOUD TOP
TEMPS WILL REMAIN ABV -10C ACROSS THE LAURELS...SO ANTICIPATE A
CONTINUATION OF THE -FZRA/FZDZ DOWN THERE FOR MOST OF THE NIGHT.
A CALL TO SOMERSET CO PENNDOT AT 05Z CONFIRMS THAT ROADS ARE ICY
DOWN THERE.
THE SNOW SHOWERS IN THE N/W SHOULD ONLY AMOUNT TO AN INCH OR SO
OVERNIGHT. UNDER OVERCAST SKIES...TEMPS WILL NOT DROP MUCH THRU
THE NIGHT. WINDS WILL BE GUSTY AS THE GRADIENT REMAINS TIGHT.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM MONDAY/...
LITTLE CHANGE FROM PREVIOUS EXPECTED ON SUNDAY. SOME LIGHT
OROGRAPHIC SNOW MAY BE ONGOING SUNDAY MORNING ACROSS THE LAUREL
HIGHLANDS. WILL CONTINUE TO FOCUS ON THE APPROACHING POTENT
CLIPPER WHICH PROMISES TO BRING ANOTHER LIGHT TO LOCALLY MODERATE
SNOW ACCUMULATION. THIS TIME IT IS THE LAURELS AND SC MOUNTAINS
MOST SHARPLY FOCUSED IN ITS CROSS HAIRS FOR SUNDAY NIGHT INTO
MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
CLIPPER WILL BRING SOME SNOW TO THE AREA LATE SUNDAY AFT INTO
MONDAY MORNING. ENERGY WILL QUICKLY TRANSFER TO THE COASTAL LOW
DURING THE DAY ON MONDAY. EXPECT THE HEAVIEST SNOW ACROSS THE
SOUTH CENTRAL PART OF THE STATE...GIVEN NW TO SE WARM FRONT.
THUS LAUREL HIGHLANS WILL LIKELY SEE HIGHEST AMTS.
DID EDGE POPS AND AMTS UP A LITTLE ACROSS THE SE...TO FIT
IN BETTER WITH LWX.
ALSO DID UP POPS ON TUESDAY. CONCERN IS THAT INVERTED
TROUGH COULD KEEP SNOW ACROSS THE WEST INTO TUE...AND COASTAL
STORM THAT DEEPENS EXTREMELY FAST MAY WRAP SNOW AROUND TO THE
WEST SIDE...A CONCERN FOR THE EAST AND SE. BLOCKING HIGH TO THE
NORTH.
STILL A LITTLE EARLY FOR AN ADVISORY ACROSS THE SOUTH.
TIGHT TEMP GRADIENT BETWEEN NY AND MD...SOME ADJUSTMENTS TO
TEMPS MONDAY INTO TUE.
WED STILL LOOKS LIKE A DRY DAY.
ANOTHER FRONTAL SYSTEM FOR LATE THU.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
DECK OF LOWER STRATUS ASSOCIATED WITH SHORTWAVE TROF ROTATING
THROUGH BEHIND DEPARTING STORM NOW OVERSPREADING THE REGION WITH
MVFR TO LIFR CONDITIONS. DOWNSLOPING MAY BE ENOUGH TO KEEP
SOUTHEAST AIRFIELDS IN VFR CONDITIONS...BUT ELSEWHERE LOOK FOR
RESTRICTIONS IN CIGS MUCH OF THE OVERNIGHT.
SOME FREEZING DRIZZLE IS NOW BEING PRODUCED OVER THE NORTHWEST
AIRFIELDS...WITH KBFD REPORTING INTERMITTENT -FZRA. THESE
CONDITIONS LIKELY THROUGH 04Z-06Z.
AN ALBERTA CLIPPER WILL TRACK JUST SOUTH OF PENNSYLVANIA SUNDAY
NIGHT INTO MONDAY...BRINGING ANOTHER ROUND OF SNOW WITH IFR
CONDITIONS TO THE REGION. THIS WILL LIKELY IMPACT MOST TAF SITES
AFTER 00Z TOMORROW...BUT SOME AFFECTS POSSIBLE KJST AND KAOO
BEFORE THIS TIME...WHICH IS REFLECTED IN THE TAFS. EXPECT A
PROLONGED PERIOD OF RESTRICTIONS INTO MON NIGHT.
OUTLOOK...
SUN...MVFR TO IFR IN THE WESTERN AND NORTHERN MOUNTAINS...VFR
ELSEWHERE.
SUN NITE...SNOW RAPIDLY OVERSPREADING FROM SW TO NE...BRINGING IFR
CONDITIONS TO THE ENTIRE REGION OVERNIGHT.
MON...WIDESPREAD IFR/MVFR IN SNOW...GRADUAL IMPROVEMENT OVERNIGHT.
TUE...AREAS MVFR IN SHSN WEST...AND ANY LINGERING SNOW IN THE EAST.
WED...NO SIG WEATHER EXPECTED.
THU...VFR TO START...WITH LATE DAY RESTRICTIONS SPREADING IN FROM
THE WEST.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
PAZ024-033.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...JUNG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1252 AM EST SUN JAN 25 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD BACK INTO THE REGION TODAY...BEFORE ANOTHER
LOW PRESSURE AREA AND TRAILING UPPER LEVEL DISTURBANCE MOVE THROUGH
MONDAY AND TUESDAY. HIGH PRESSURE RETURNS DURING THE LATTER HALF OF
NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1245 AM...STRATOCU ASSOCIATED WITH VERY SHALLOW W/NW FLOW
MOISTURE IS ALREADY MAKING ITS RETREAT INTO SW VIRGINIA AND SE
KENTUCKY. SKY COVER HAS BEEN REDUCED SUBSTANTIALLY ACROSS THE TENN
BORDER COUNTIES FOR THE DURATION OF THE EARLY MORNING. OTHERWISE...
MIN TEMPS SHOULD AVERAGE AROUND NORMAL IN MOST LOCATIONS...ALTHOUGH
PERSISTENT MIXING IN THE MAJOR MTN VALLEYS MAY ACTUALLY YIELD ABOVE
CLIMO MINS. WINDS CONTINUE TO GUST TO 30-40 KTS ACROSS THE NRN
MTNS...MAINLY IN EXPOSED LOCATIONS. HOWEVER...WINDS ARE PROBABLY AT
OR NEAR THEIR PEAK...AS THE FLOW IS ALREADY BACKING IN RESPONSE TO
THE NEXT MAJOR VORT MAX DROPPING OUT OF THE NORTHERN PLAINS. THE
ADVISORY WILL BE ALLOWED TO CONTINUE FOR NOW...BUT THE PLAN IS TO
DROP IT BY 4 AM.
AS OF 1020 PM EST...WINDS HAVE SUDDENLY COME UP STRONGLY BEHIND THE
PASSING APPALACHIANS WAVE...WITH BOONE TO WEST JEFFERSON GUSTING 40
TO 50 KT...AND SOME HIGHER PEAKS FROM MT MITCHELL TO GRANDFATHER
STARTING TO SHOW SOLID ADVISORY VALUES. THE LATEST RAP RUNS HAVE NW
WINDS INCREASING FURTHER THROUGH 06Z...SO A WIND ADVISORY WILL BE
ISSUED FOR THE NRN THREE COUNTIES UNTIL 6 AM...WHEN THE GRADIENT
SHOULD HAVE SLACKENED.
OTHERWISE...A BRIEF PERIOD OF RESIDUAL NW FLOW MOISTURE BEHIND A
SHORTWAVE CROSSING THE APPALACHIANS WILL PEAK AROUND 06Z. ISOLD
LIGHT SNOW SHOWERS OR PATCHY FREEZING DRIZZLE WILL BE POSSIBLE...BUT
CHANCES LOOK TOO SMALL THIS FAR SOUTH OF THE BETTER MOISTURE TO
FEATURE ANY SNOW/ICE AMOUNTS. THE OTHER CONCERN WILL BE FOR VERY
PATCHY BLACK ICE IN LOCATIONS WHERE WET ROADS MIGHT HAVE LINGERED
INTO THE EVENING HOURS FROM EARLY DAY PRECIPITATION. ALTHOUGH THIS
COULD BE A MINOR CONCERN FROM THE NC MTNS TO PARTS OF THE NW
PIEDMONT...THERE APPEARS TO HAVE BEEN JUST ENOUGH DRYING THIS
AFTN/EVENING TO NOT REQUIRE AN SPS. EXPECT OVERNIGHT LOWS AROUND
NORMAL.
SHORT WAVE RIDGING WILL DEVELOP OVER THE AREA SUNDAY AHEAD OF A
STRONG CLIPPER SYSTEM MOVING INTO THE MID MISSISSIPPI VALLEY. LOW
LEVEL FLOW WILL BECOME SLY AHEAD OF THE ASSOCIATED SFC LOW. AFTER
CLEARING SKIES ACROSS THE MTNS DURING THE MORNING AS LOW LEVEL
MOISTURE DEPARTS...CLOUDS MOVE BACK IN IN THE DEVELOPING WAA
PATTERN. ISOLATED SHRA MAY ALSO DEVELOP ACROSS THE MTNS VERY LATE IN
THE DAY AS DEEP MOISTURE INCREASES...BUT NO SIGNIFICANT QPF IS
EXPECTED. CLOUDS WILL INCREASE LATE IN THE DAY OUTSIDE OF THE
MTNS...BUT MOSTLY SUNNY SKIES WILL PREVAIL FOR THE BULK OF THE DAY.
HIGHS WILL BE A FEW DEGREES ABOVE NORMAL ACROSS THE CWFA.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 230 PM SATURDAY...THE POTENT CLIPPER SYSTEM WILL CROSS THE
CWFA SUNDAY NIGHT THRU MONDAY MORNING PER LATEST CONSENSUS. GUIDANCE
CONTINUES TO BE IN GOOD AGREEMENT ON THE TIMING. BEST Q-VECTOR
CONVERGENCE LOOKS TO BE AROUND 00-06Z MON...SHIFTING EAST BY 12Z.
STEEP LOW-MID LVL LAPSE RATES AND DECENT MOISTURE SHUD RESULT IN
GOOD COVERAGE OF PRECIP ACRS THE HIGH TERRAIN OVERNIGHT...WITH SOME
ACTIVITY BEING ABLE TO DEVELOP EAST OF THE MTNS. WITH MID LVL
THICKNESSES CRASHING...COUPLED WITH WEAK SBCAPE (UP TO 150
J/KG)...MAY SEE CONVECTIVE SNOW SHWRS ACRS THE MTNS. IN THE LWR
ELEVATIONS...ALL INDICATIONS ARE THAT THE SFC-BASED WARM LAYER WILL
PROBABLY JUST BE TOO WARM. IF THE BEST FORCING IS ABLE TO OCCUR
DURING THE WEE MORNING HOURS...CANNOT RULE OUT SPOTTY SNOW SHWRS
ACRS NE GA AND THE WRN UPSTATE. BASED ON CURRENT TIMING...IT LOOKS
LIKE THE NC FOOTHILLS AND PIEDMONT HAVE A BETTER SHOT AT SEEING A FEW
FLAKES...BUT EVEN THERE...NOT EXPECTING ANY WIDESPREAD ACCUMS. EVEN
IN THE MTNS...ACCUMS MAY STRUGGLE TO REACH ADVISORY CRITERIA...AS
LLVL FLOW WILL BE OUT OF THE WEST-SOUTHWEST OVERNIGHT. FOR TEMPS...I
WENT CLOSE TO THE MOS CONSENSUS...MAINLY IN THE UPR 20S TO MID 30S
MTNS AND UPR 30S-40 PIEDMONT.
AS THE MID LVL LOW PASSES TO THE EAST MONDAY MORNING...LLVL FLOW
WILL VEER TO NWLY...BUT NEVER GETS ALL THAT STRONG. SO ONLY LIGHT
ADDITIONAL NW FLOW SNOW ACCUMS ARE EXPECTED ALONG THE TN LINE DURING
THE DAY. EAST OF THE MTNS...FCST SNDGS SHOW LINGERING LLVL MOISTURE
WITHIN WEAK NW FLOW...BUT FORCING SHUD WANE FOR ANY PRECIP. TEMPS
WILL WARM INTO THE MID 30S TO LWR 40S IN THE MTNS...AND UPR 40S TO
LWR 50S ACRS THE PIEDMONT.
MONDAY NIGHT AND TUESDAY...ANOTHER SHORTWAVE WILL DIVE SOUTHEAST
ACRS THE OHIO VALLEY...AND REINFORCE NWLY FLOW ATOP THE CWFA. IN
FACT...THE 12Z NAM AND GFS AGREE ON BETTER OVERALL NW FLOW SETUP
ACRS THE SOUTHERN APPALACHIANS...ESPECIALLY AROUND MIDDAY TUESDAY.
ON THE PLAN VIEW...THE 925-850 MB FLOW ALSO SEEMS TO COME OFF THE
GREAT LAKES TO THE NC MTNS. SO MAY SEE DIURNALLY-ENHANCED CONVECTIVE
SNOW SHWRS DEVELOPING ACRS ERN KY/TN...THEN INTO THE NC
MTNS...PRODUCING A QUICK 1-2" OF SNOW. I WILL PLAN TO ADD A MENTION
OF SNOW ACCUM IN THE HWO ALONG THE TN BORDER FOR TUESDAY.
OTHERWISE...EXPECT GENERALLY MOSTLY CLEAR SKIES AND BELOW NORMAL
TEMPS ACRS THE REGION.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 200 PM SAT...THE PERSISTENT DEEP TROUGH OVER THE ERN SEABOARD
WILL FINALLY MOVE OFF THE EAST COAST WEDNESDAY ALLOWING A SHORT RIDGE
AND HIGH PRESSURE TO BUILD ACROSS THE CWFA. COLD ADVECTION AND MOIST
NW FLOW WILL CONTINUE TUE NIGHT INTO WED...WITH POPS ACCORDINGLY
CONTINUED NEAR THE TENN BORDER. DRY AND SETTLED WEATHER RETURN
BRIEFLY BEFORE THE NEXT CLIPPER MOVES IN LATE THURSDAY. THE CLIPPER
WILL HAVE ABSORBED A WEAK WAVE IN THE SRN STREAM AND IS PROGGED TO
PUSH A WEAK COLD FRONT INTO THE DEEP SOUTH AND CAROLINAS THU NIGHT.
CHC POPS FOR THE UPSLOPE AREAS OF THE MTNS WILL BE ADVERTISED...IN
ADDITION TO SCHC POPS IN THE PIEDMONT AFFORDED BY THE PRESENCE OF
SOME LLVL FORCING. HIGH PRESSURE RETURNS IN THE WAKE OF THE FRONT AS
THE UPPER FLOW BECOMES MORE ZONAL. REGARDING FURTHER EVOLUTION...THE
24/12Z RUNS OF THE GFS AND EC DIVERGE BY THE WEEKEND. EC BRINGS
ANOTHER CLIPPER INTO THE CENTRAL APPALACHIANS BY SATURDAY NIGHT WITH
AN ERN TROUGH DEVELOPING AFTERWARD. GFS IS A BIT MORE ACTIVE WITH THE
SRN STREAM DURING THE SAME PERIOD...SHOWING RETURN FLOW OVER THE HIGH
WHICH DEVELOPS INTO A WEDGE. BOTH MODELS KEEP US DRY THRU SATURDAY
HOWEVER. TEMPS WILL REMAIN IN A SEASONABLE RANGE THRU THE FCST
PERIOD...STARTING OFF A COUPLE DEGREES BELOW NORMALS...BUT WARMING
WED-THU PRIOR TO THE FROPA AND A SUBSEQUENT RETURN OF READINGS A BIT
BELOW NORMAL.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...VFR CONDITIONS THROUGH THE PERIOD...
ALTHOUGH SOME VALLEY FOG MAY OCCUR IN THE MTNS WEST OF KAVL LATER
THIS MORNING. LIGHT WSW WINDS ARE EXPECTED TO PERSIST THOUGH THE
OVERNIGHT (NW AT KAVL)...BECOMING SOUTH AT 5-10 KTS DURING THE
AFTERNOON...AHEAD OF THE NEXT COLD FRONT/UPPER AIR DISTURBANCE. VFR
CIGS BETWEEN 050-100 ARE EXPECTED TO OVERSPREAD THE AREA QUICKLY
DURING THE EVENING IN ADVANCE OF THIS SYSTEM. PRECIP CHANCES WILL
ALSO INCREASE BY THE END OF THE PERIOD...MAINLY ACROSS THE MTNS...
BUT WILL WITHHOLD THIS MENTION UNTIL CONFIDENCE IN TIMING INCREASES.
OUTLOOK...A SERIES OF CLIPPER SYSTEMS WILL BRING PERIODIC CHANCES
FOR SNOW SHOWERS...MAINLY TO THE MOUNTAINS THROUGH THE WEEK. MOST OF
THESE SNOW SHOWERS WILL REMAIN WEST AND NORTH OF KAVL...BUT BRIEF
PERIODS OF RESTRICTIONS AND SNOW SHOWERS CANNOT BE RULED OUT THERE.
OTHERWISE...MAINLY VFR CONDITIONS ARE EXPECTED.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 94%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 97%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...WIND ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR NCZ033-049-
050.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...HG/JDL/RWH
SHORT TERM...ARK
LONG TERM...WIMBERLEY
AVIATION...JDL
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1150 AM CST SUN JAN 25 2015
.DISCUSSION...
UPPER SHORTWAVE MOVING TOWARD THE MID STATE THIS AFTERNOON. AS
THE SFC LOW AND FRONTAL BOUNDARY DESCENDS UPON THE MID STATE...WAA
OUT AHEAD OF THE BOUNDARY IS PUSHING TEMPS UPWARD AND THEY ARE
ALREADY APPROACHING MAX TEMPS FOR TODAY...WEST OF PLATEAU. WILL
THEREFORE ELECT TO RAISE MAX TEMPS A FEW DEGREES.
OTHERWISE...RADAR SHOWING LEADING EDGE OF THE RAIN SHOWER ACTIVITY
NOW INTO OUR WESTERNMOST COUNTIES. HRRR CONCURS WITH THIS BUT DEF
POPS WILL NEED TO BE TRIMMED BACK TO LIKELY FOR OUR CENTRAL AREAS.
THE TIMING APPEARS TO BE A LITTLE SLOWER. BUT...CERTAINLY BY
00Z...THE DEEPER MOISTURE WILL BE UPON US.
NO OTHER CHANGES NEEDED...STILL SEEING SOME GUSTS...PARTICULARLY
OUTAHEAD OF THE LEADING EDGE OF PRECIP WHERE MORE IN THE WAY OF
SUBSIDENCE EXISTS.
UPDATE OUT SHORTLY.
&&
.PREV DISCUSSION... /ISSUED 1136 AM CST SUN JAN 25 2015/
AVIATION 18Z DISCUSSION...
UPPER LEVEL SHORTWAVE TO MOVE ACROSS KY DURING THE TAF PD. THIS
WILL PRODUCE RAIN SHOWER ACTIVITY ACROSS THE MID STATE BEGINNING
A LITTLE LATER THIS AFTERNOON AND CONTINUING INTO TONIGHT. OF
FURTHER CONSEQUENCE...FREEZING LEVELS WILL DROP TO SUFFICIENT SNOW
LEVELS AND WE WILL SEE THE TAIL END OF THE PRECIPITATION SWITCH TO
SNOW BETWEEN 08Z AND 12Z. THE LIGHT SNOW WILL
CONTINUE...ESPECIALLY NEAR CSV...FROM 12Z THRU 16Z.
AS FOR CIGS AND VSBYS...IFR LEVEL CIGS ARE EXPECTED TO BEGIN
BETWEEN 21Z AND 00Z. THE LOW CIGS WILL CONT THRU THE TAF PD.
VSBYS NOT LOOKING TOO BAD. REDUCTIONS DUE TO SNOWFALL SHOULD
MINIMAL GIVEN THE EXPECTED LIGHT NATURE OF THE SNOW.
PREV DISCUSSION... /ISSUED 548 AM CST SUN JAN 25 2015/
UPDATE...FOR 12Z AVIATION FORECASTS.
AVIATION...A FAST-MOVING LOW PRESSURE AREA WILL PUSH INTO EXTREME
SOUTHERN ILLINOIS BY 18Z, BRINGING MVFR CONDITIONS TO CKV BY 17Z
AND TO BNA BY 19Z. AS THE LOW PUSHES SOUTHEASTWARD INTO KENTUCKY
DURING THE AFTERNOON, EXPECT MVFR CONDITIONS TO DEVELOP AT CSV BY
22Z. CONDITIONS WILL DETERIORATE TO IFR AT ALL TERMINALS LATE THIS
AFTERNOON AND EVENING, WITH LIFR AT CSV BY 02Z. SFC WINDS WILL
BECOME GUSTY AND SWITCH FROM SOUTH, TO WEST, TO NORTHWEST, AS THE
LOW PRESSURE AREA PASSES ACROSS KENTUCKY LATER TODAY AND TONIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 54 33 39 32 / 70 60 20 10
CLARKSVILLE 53 30 40 32 / 90 70 10 10
CROSSVILLE 50 32 37 28 / 30 80 50 20
COLUMBIA 54 33 41 32 / 70 60 10 10
LAWRENCEBURG 55 33 41 32 / 60 60 10 10
WAVERLY 53 32 41 31 / 90 60 10 05
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1124 AM CST SUN JAN 25 2015
.AVIATION...
GENERALLY CLEAR SKY EXPECTED WITH ONLY HIGH CLOUDS FORESEEN. SURFACE
WINDS ARE NOW BEING FORECAST TO BE OF LESSER SPEEDS THAN PREVIOUSLY
THOUGHT...DUE TO DETERIORATION OF SURFACE PRESSURE GRADIENT CURRENTLY
UNDERWAY ACROSS WESTERN PART OF FORECAST AREA. RUC 850 MB WIND
ANALYSIS ALSO DEPICTING A DECREASE IN WIND SPEEDS. THUS...GUSTS IN
THE 20 TO 25 KT RANGE WILL BE FORECAST FOR ONLY KGUY AND KAMA...WITH
CESSATION OF SAME BEGINNING AROUND 23Z TODAY. LIGHT WESTERLY SURFACE
WINDS EXPECTED OVERNIHGT WITH NO VISIBILITY RESTRICTIONS EXPECTED.
VFR FORECAST CONTINUES NEXT 24 HOURS.
COCKRELL
&&
.PREV DISCUSSION... /ISSUED 540 AM CST SUN JAN 25 2015/
AVIATION...12Z TAFS
VFR CONDITIONS WILL PREVAIL. WINDS WILL GET GUSTY FROM THE NW TODAY
AND THEN DIE BACK DOWN AROUND SUNSET.
SIMPSON
PREV DISCUSSION... /ISSUED 420 AM CST SUN JAN 25 2015/
SHORT TERM...TODAY AND TONIGHT
A COLD FRONT THAT PUSHED THROUGH THE TEXAS/OKLAHOMA PANHANDLES LAST
NIGHT WILL CONTINUE TO MOVE SOUTHWARD TODAY. COLD AIR ASSOCIATED WITH
AN UPPER LEVEL DISTURBANCE OVER WESTERN MISSOURI WILL REMAIN NORTH OF
THE AREA SO THIS FRONT WILL HAVE LITTLE EFFECT ON THE TEMPERATURES
ACROSS THE AREA TODAY. MEANWHILE DRY NORTHWEST UPPER FLOW WILL
MAINTAIN A STRETCH OF DRY AND MILD CONDITIONS OVER THE AREA. HIGH
TEMPERATURES WILL BE A LITTLE WARMER TODAY DUE TO THE DIMINISHING
SNOW COVER...WITH HIGHS IN THE 50S TO AROUND 60 DEGREES. HOWEVER A
LOW-LEVEL JET OVER CENTRAL KANSAS/OKLAHOMA WILL LEAD TO BREEZY
NORTHWEST WINDS THAT CAN MAKE IT FEEL A BIT CHILLIER. THE STRONGEST
WINDS ARE EXPECTED TO BE OVER THE EASTERN OKLAHOMA AND NORTHEAST
TEXAS PANHANDLE...CLOSER TO THIS JET. WINDS WILL DIMINISH BY AROUND
SUNSET WHILE BACKING A BIT TO THE WEST. OVERNIGHT LOWS WILL BE
MILDER...RANGING FROM THE MID 20S IN THE NORTHWEST TO THE MID 30S IN
THE SOUTHEAST TEXAS PANHANDLE.
LONG TERM...MONDAY THROUGH SATURDAY
THE WARMING TREND WILL CONTINUE INTO THE FIRST PART OF THE EXTENDED
FORECAST AS AN AMPLIFIED UPPER-LEVEL RIDGE MOVES OVER THE ROCKIES TO
THE SOUTHERN PLAINS. DOWNSLOPING SOUTHWEST WINDS WILL PUSH
TEMPERATURES WELL INTO THE 60S AND EVEN LOW 70S MONDAY THROUGH
WEDNESDAY. HOWEVER THE RIDGE WILL START TO FLATTEN TUESDAY AS AN
UPPER-LEVEL DISTURBANCE LIFTS NORTHEAST OUT OF THE BAJA PENINSULA.
THIS SYSTEM WILL ALSO SEND A COLD FRONT THROUGH THE AREA WEDNESDAY
EVENING...COOLING HIGH TEMPERATURES BACK INTO THE 50S FOR THURSDAY.
THE UPPER PATTERN BECOMES MORE ACTIVE TOWARD THE END OF THE WEEK AS
ANOTHER UPPER LOW DEEPENS OVER BAJA CALIFORNIA. HOWEVER MUCH UNCERTAINTY
EXITS IN THE TRACK OF THIS SYSTEM ALONG WITH EVENTUAL PRECIP TYPE.
THE GFS CONTINUES TO GENERATE A LOT OF QPF ACROSS THE AREA AS
ISENTROPIC LIFT INCREASES ALONG WITH AN INFLUX OF LOW-LEVEL
MOISTURE. THE GFS ALSO TRACKS THIS UPPER LOW A LITTLE FURTHER TO THE
EAST THAN THE ECMWF. WHILE THIS SYSTEM HAS ITS ORIGINS IN THE
PACIFIC AND WITH THE COLD AIR WELL NORTH OF THE AREA INITIALLY...PRECIP
TYPE WILL START OUT AS RAIN FRIDAY. CAN SEE A RAIN SNOW MIX FRIDAY
EVENING AS TEMPERATURES COOL OFF TO NEAR THE FREEZING MARK. THE GFS
ALSO SUGGESTS MORE IN THE WAY OF WINTRY PRECIPITATION SATURDAY AS
IT BRINGS THE SOUTHERN FRINGES OF THE COLD AIR OVER THE GREAT LAKES
AREA FURTHER SOUTH THAN THE ECMWF.
PRECIP SHOULD END SUNDAY HOWEVER THIS UPPER LOW WILL EVENTUALLY LIFT
NORTHEAST INTO THE FOUR CORNERS REGION THE FOLLOWING WEEK. THIS IS
BEYOND THE SCOPE OF THIS FORECAST PACKAGE BUT BEARS WATCHING AS THIS
CAN BRING ANOTHER CHANCE OF PRECIPITATION TO THE AREA THEN.
CLK
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
03/20
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
856 PM CST MON JAN 26 2015
.UPDATE...
ISSUED AT 856 PM CST MON JAN 26 2015
CONDITIONS HAVE GREATLY IMPROVED OVER THE PAST HOUR. THIS IS DUE
TO A COMBINATION OF DIFFERENT REASONS:
1. PRECIPITATION HAS BEEN ON THE WANE. THERE WAS A NICELY EVIDENT
VORT MAX ON RADAR THAT CAME THROUGH THE FORECAST AREA BETWEEN
23-01Z. SUBSIDENCE IN THE WAKE OF THIS VORT HAS HELPED TO SQUASH A
LOT OF THE DEVELOPMENT PREVIOUS MODEL RUNS WERE SUGGESTING ALONG
THE INVERTED SURFACE TROUGH. ADDITIONALLY...SURFACE CONVERGENCE
ALONG THE TROUGH IS NOT THAT STRONG AS WINDS HAVE DIMINISHED SOME
WEST OF THE MISSISSIPPI RIVER. LASTLY...ALL THE PREVIOUS SNOW
THAT WAS UP IN NORTHWEST WISCONSIN HAS NOW PROGRESSED TO THE
SOUTHEAST INTO EASTERN WI AND OUT OF THE FORECAST AREA.
2. ROADS HAVE BEEN IMPROVING RESULTING FROM TREATMENTS WORKING ON
THEM. THE DIMINISHING OF PRECIPITATION HAS ONLY AIDED THIS MORE.
DUE TO THE IMPROVING CONDITIONS...HAVE CANCELLED THE WINTER
WEATHER ADVISORY EARLY. STILL CANNOT RULE OUT SOME PATCHY LIGHT
FREEZING DRIZZLE OR LIGHT SNOW WITH THAT INVERTED TROUGH
AROUND...BUT NOT ENOUGH COVERAGE EXISTS TO WARRANT THE ADVISORY
OUT ANYMORE.
UPDATE ISSUED AT 459 PM CST MON JAN 26 2015
HAVE EXPANDED THE ADVISORY INTO FAR SOUTHWEST WISCONSIN WHERE
NUMEROUS REPORTS OF BAD ROADS HAVE BEEN RECEIVED...ESPECIALLY
SECONDARY ROADS.
ALSO HAVE EXTENDED THE ADVISORY UNTIL MIDNIGHT. A WARM FRONT SITS
ALONG THE MISSISSIPPI RIVER...WHICH APPEARS TO BE STUCK NOW THAT
ITS PARALLEL WITH THE UPPER LEVEL FLOW. ADDITIONALLY...A SURFACE
LOW OVER NORTHWEST WI WILL RIDE DOWN ALONG THIS FRONT...SETTING UP
AN INVERTED TROUGH IN ITS WAKE. LOW LEVEL VERTICAL MOTION SHOULD
PERSIST ALONG AND EAST OF THIS BOUNDARY...AND WITH TEMPERATURES IN
THIS ZONE BELOW FREEZING...WE SHOULD SEE A CONTINUATION OF
FREEZING DRIZZLE THROUGH THE EVENING. THIS IS SHOWN NICELY IN THE
LATEST HRRR RUNS...RAP...26.12Z REGIONAL CANADIAN AND 26.18Z NAM.
ANOTHER CONCERN IS THE MASS OF SNOW MARCHING SOUTH OUT OF
NORTHWEST WISCONSIN...WHICH SHOULD MARCH DOWN THROUGH CENTRAL WI
OVER THE NEXT FEW HOURS. THE COMBINATION OF THIS SNOW AND
FREEZING DRIZZLE WARRANTS A CONTINUATION OF THE ADVISORY. LUCKILY
IMPACTS SHOULD CONTINUE TO DECREASE AS ROADS CONTINUE TO BE
TREATED...THOUGH THE LOSS OF DAYTIME HEATING WILL ALLOW UNTREATED ROADS
TO COOL AND MAKE THINGS WORSE.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 331 PM CST MON JAN 26 2015
MAIN FORECAST PROBLEM WILL BE LINGERING FREEZING DRIZZLE
CHANCES THROUGH THIS EVENING.
SURFACE MAP THIS AFTERNOON HAS SURFACE LOW OVER THE ARROWHEAD WITH A
WARM FRONT EXTENDING ACROSS EASTERN MN/IA. TEMPERATURES RANGED FROM
THE MIDDLE 30S TO MIDDLE 40S BEHIND THE FRONT ACROSS SOUTHEAST
MN/NORTHEAST IA...TO THE LOWER TO MIDDLE 20S EAST OF THE MISSISSIPPI
RIVER/AHEAD OF THE FRONT. LOWER LEVEL ISENTROPIC LIFT ACROSS THIS
FRONT WAS PRODUCING AREAS OF FREEZING DRIZZLE EAST OF THE
MISSISSIPPI WITH REPORTS OF SOME SLIPPERY STRETCHES ON ROADWAYS VIA
WI 511 AND FROM LOCAL ROAD CREW.
LOOK FOR THE SURFACE LOW TO MOVE SOUTHEAST FROM THE ARROWHEAD OF MN
THIS AFTERNOON INTO NORTHWEST IL BY EARLY THIS EVENING. MAIN LIFT
AHEAD OF THIS LOW ...WHICH IS PRESENTLY CAUSING THE FREEZING DRIZZLE
WILL THEREFORE BE IN A WANING PHASE WITH ITS PASSAGE. HOWEVER...RAP
BUFKIT SOUNDING SHOWS SOME LINGERING LIFT ACROSS CENTRAL WI THROUGH
LATER THIS EVENING AS THE MID-LEVEL/SURFACE INVERTED TROUGH HANGS
UP. WILL THEREFORE CONTINUE TO CARRY FREEZING DRIZZLE MENTION INTO
THIS EVENING. THERE MAY BE SOME LIGHT SNOW AS WELL WITH POCKETS OF
FEEDER/SEEDER ICE. MAY HAVE TO EXTEND CURRENT ADVISORY A LITTLE
LONGER INTO THIS EVENING TO COVER FOR THIS. WILL KEEP A CLOSE EYE ON
IT.
HIGH PRESSURE BUILDS OVER THE AREA LATER TONIGHT THROUGH TUESDAY FOR
QUIET WEATHER. LOOKS LIKE IT WILL REMAIN MOSTLY CLOUDY THOUGH DESPITE
HIGH BUILDING IN DUE TO MOISTURE BEING TRAPPED UNDER THE SUBSIDENCE
INVERSION. WITH PARTIAL SUNSHINE LATE IN THE MORNING THROUGH THE
AFTERNOON...PLAN ON HIGHS REBOUNDING INTO THE 30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 331 PM CST MON JAN 26 2015
UNSEASONABLY MILD CONDITIONS EXPECTED FOR WEDNESDAY AHEAD OF
APPROACHING LOW PRESSURE ACROSS THE PLAINS. DESPITE AN INCREASE IN
STRATUS CLOUD...LOOK FOR HIGHS WELL INTO THE 30S WITH POSSIBLY A FEW
LOWER 40 READINGS ACROSS PARTS OF NORTHEAST IA INTO FAR SOUTHWEST WI.
A WINTRY MIX LOOKS TO IMPACT THE AREA WEDNESDAY NIGHT INTO THURSDAY
MORNING AS THE LOW OVER THE PLAINS MOVES TOWARD THE GREAT LAKES
REGION. MODEL SOUNDINGS NOT SHOWING A LOT OF ICE IN CLOUD FOR SNOW
PRODUCTION...SO LOOKS LIKE MORE OF A FREEZING RAIN/DRIZZLE POTENTIAL
AS A RESULT. WILL CONTINUE TO MONITOR THIS.
LATEST GFS/ECMWF SHOW ANOTHER STORM SYSTEM MOVING OUT OF THE PLAINS
TOWARD THE UPPER MISSISSIPPI RIVER REGION SATURDAY AFTERNOON INTO
SUNDAY FOR SNOW CHANCES.
OTHERWISE...LOOKS LIKE A SIGNIFICANT COOL DOWN THROUGH THE
WEEKEND/EARLY NEXT WEEK AS PATTERN SHIFTS TO NORTHWEST FLOW ALOFT.
HIGHS ON SATURDAY EXPECTED TO BE IN THE 20S...COOLING INTO THE
SINGLE DIGITS/TEENS BY MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 540 PM CST MON JAN 26 2015
A LOW PRESSURE TROUGH HAS STALLED OUT ALONG THE MISSISSIPPI RIVER.
WEST OF THE TROUGH AT RST...CEILINGS ARE VFR...BUT ALONG THE
TROUGH AT LSE CEILINGS ARE MVFR. THIS TROUGH IS EXPECTED TO REMAIN
IN PLACE THROUGH TUESDAY...HELPING TO MAINTAIN LOW STRATUS AND
POSSIBLY EVEN PRODUCE SOME -FZDZ AT LSE THIS EVENING. A WEAKENING
TREND TO THE TROUGH WILL HELP TO DIMINISH THE -FZDZ THREAT AFTER
MIDNIGHT. ADDITIONALLY...A COLD FRONT NORTH OF MSP IS FORECAST TO
DROP THROUGH RST THIS EVENING. THE COLDER AIR RUSHING INTO THE
MOIST AIRMASS IN PLACE SHOULD ALLOW CEILINGS TO FALL THROUGH THE
MVFR AND EVENTUALLY IFR RANGE BY TUESDAY MORNING. CEILINGS AT BOTH
TAF SITES SHOULD RISE GRADUALLY TUESDAY AFTERNOON AS THE TROUGH
WEAKENS AND DAYTIME MIXING ASSISTS.
NO VISIBILITY IMPACTS ARE EXPECTED THROUGH TUESDAY WITH ENOUGH
MIXING TAKING PLACE NEAR THE GROUND.
REGARDING WINDS...A 15 KT BREEZE CONTINUES AT RST...BUT SHOULD
GRADUALLY DIMINISH AND TURN NORTHERLY OVERNIGHT AS THE PRESSURE
GRADIENT WEAKENS. WITH THE TROUGH OVER LSE...LOOK FOR LIGHT WINDS
THERE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
550 PM CST MON JAN 26 2015
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
AND NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 545 PM CST MON JAN 26 2015
QUICK CHECK WITH WOOD COUNTY INDICATED ROADS JUST SNOW COVERED...
WITH NO MAJOR TRAVEL PROBLEMS REPORTED. WILL ALLOW THE ADVISORY
TO EXPIRE AT 600 PM.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 245 PM CST MON JAN 26 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAKENING
LOW PRESSURE SYSTEM MOVING SSE AS IT APPROACHES FAR NORTHWEST
WISCONSIN. AHEAD OF THE LOW...MODEST WARM ADVECTION AND MID-LEVEL
FGEN ARE CONTRIBUTING TO A BAND OF SNOW...BUT THE BEST RETURNS
APPEAR TO BE EXITING CENTRAL WISCONSIN EARLY THIS AFTERNOON. THE
LATEST DATA SHOW THAT THE MID-LEVEL FGEN WILL CONTINUE TO WEAKEN AS
THE BEST WARM ADVECTION PULLS OUT...SO SHOULD SEE ONLY VERY LIGHT
SNOW OR FLURRIES FOR A PERIOD UNTIL BETTER RETURNS OVER WESTERN LAKE
SUPERIOR ARRIVE. STILL SEEING OBSERVATIONS AT MARSHFIELD AND
MEDFORD OF FREEZING DRIZZLE OR UNKNOWN PRECIP...SO NO PLANS TO
CHANGE THE ADVISORY. SOME POSSIBILITY THAT IT COULD GET EXTENDED
INTO THE EVENING...BUT NO INDICATIONS OF FREEZING DRIZZLE ELSEWHERE
THOUGH. SNOWFALL ACCUMS AND IMPACTS REMAIN THE MAIN FORECAST
CONCERNS.
TONIGHT...CLIPPER LOW PRESSURE WILL CONTINUE TO WEAKEN AS IT TRACKS
ACROSS FAR SW WISCONSIN EARLY THIS EVENING AND INTO WESTERN
ILLINOIS. ANOTHER AREA OF LIGHT SNOW ASSOCIATED WITH WARM ADVECTION
WILL MOVE ACROSS NORTH-CENTRAL AND EASTERN WISCONSIN THAT WILL
PROLONG THE LIGHT SNOW FOR MUCH OF THE EVENING. THE SNOW WILL
LIKELY DIMINISH OVER CENTRAL WISCONSIN BY MID TO LATE EVENING...BUT
SATURATION WILL REMAIN DEEP ENOUGH FOR PATCHY FREEZING DRIZZLE...SO
LEFT THAT POSSIBILITY IN THE FORECAST ON THE WESTERN EDGE OF THE
PRECIP. THE HIGHEST ACCUMULATIONS WILL BE OVER EASTERN WISCONSIN
WHERE A HALF INCH OR INCH WILL LIKELY FALL. LIGHT ONSHORE FLOW FROM
SE WINDS MAY LOCALLY BOOST TOTALS HIGHER OVER THE DOOR PENINSULA
FROM LAKE ENHANCEMENT. MOST GUIDANCE SUPPORTS LIGHT PRECIP
DIMINISHING LATE TONIGHT ACROSS THE EAST...THOUGH FLURRIES COULD
CONTINUE IN THE EAST DUE TO THE LIGHT ONSHORE FLOW. LOWS MAINLY
BETWEEN 19-24 DEGREES.
TUESDAY...BECAUSE WEAK LOW LEVEL CONVERGENCE WILL BE
CONTINUING...THINK OVERCAST CONDITIONS WILL PERSIST THROUGH MUCH OF
THE MORNING HOURS. AS ARCTIC HIGH PRESSURE TRIES TO REBUILD INTO
THE REGION DURING THE AFTERNOON...SHOULD SEE THE LOW OVERCAST ERODE
FROM THE WEST AND ALSO THE EAST WHICH WILL LEAD TO INCREASING
SUNSHINE. HIGHS WILL RANGE FROM THE UPPER 20S TO LOWER 30S.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 245 PM CST MON JAN 26 2015
A COUPLE OF WEAK UPPER TROUGHS WILL APPROACH FROM THE WEST
WEDNESDAY NIGHT AND BRING SOME LIGHT SNOW TO THE REGION. NOT
MUCH MOISTURE AVAILABLE BUT THERE IS PRETTY GOOD LOW LEVEL WARM
ADVECTION AND CONVERGENCE IN NORTHEAST WISCONSIN. THINK WE WILL
GET 1 TO 3 INCHES WITH THE GREATEST AMOUNTS OVER DOOR MARINETTE
AND FLORENCE AND FOREST COUNTIES.
LAKE EFFECT SNOW SHOWERS POSSIBLE IN NORTHCENTRAL WISCONSIN
WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT BUT ACCUMULATIONS SHOULD
BE LIGHT. DRY AND COLDER FRIDAY AND SATURDAY. AN ARCTIC COLD
FRONT WILL APPROACH THE AREA SATURDAY NIGHT AND SUNDAY AND SHOULD
BE ABLE TO PRODUCE SOME LIGHT SNOW AS IT MOVES ACROSS THE AREA.
MONDAY SHOULD BE QUITE COLD WITH SUBZERO HIGHS POSSIBLE IN
NORTHERN WISCONSIN.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 545 PM CST MON JAN 26 2015
ALTHOUGH THE SYSTEM PRODUCING THE SNOW WILL SLOWLY SHIFT OFF TO
THE SE TNGT...MVFR/IFR CIGS WILL LINGER IN THE MOIST CYCLONIC FLOW
REMAINING BEHIND THE DEPARTING SYSTEM. CIGS IN CENTRAL WI MAY EVEN
DROP INTO THE LIFR CATEGORY FOR A WHILE OVERNIGHT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ035.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
540 PM CST MON JAN 26 2015
.UPDATE...
ISSUED AT 459 PM CST MON JAN 26 2015
HAVE EXPANDED THE ADVISORY INTO FAR SOUTHWEST WISCONSIN WHERE
NUMEROUS REPORTS OF BAD ROADS HAVE BEEN RECEIVED...ESPECIALLY
SECONDARY ROADS.
ALSO HAVE EXTENDED THE ADVISORY UNTIL MIDNIGHT. A WARM FRONT SITS
ALONG THE MISSISSIPPI RIVER...WHICH APPEARS TO BE STUCK NOW THAT
ITS PARALLEL WITH THE UPPER LEVEL FLOW. ADDITIONALLY...A SURFACE
LOW OVER NORTHWEST WI WILL RIDE DOWN ALONG THIS FRONT...SETTING UP
AN INVERTED TROUGH IN ITS WAKE. LOW LEVEL VERTICAL MOTION SHOULD
PERSIST ALONG AND EAST OF THIS BOUNDARY...AND WITH TEMPERATURES IN
THIS ZONE BELOW FREEZING...WE SHOULD SEE A CONTINUATION OF
FREEZING DRIZZLE THROUGH THE EVENING. THIS IS SHOWN NICELY IN THE
LATEST HRRR RUNS...RAP...26.12Z REGIONAL CANADIAN AND 26.18Z NAM.
ANOTHER CONCERN IS THE MASS OF SNOW MARCHING SOUTH OUT OF
NORTHWEST WISCONSIN...WHICH SHOULD MARCH DOWN THROUGH CENTRAL WI
OVER THE NEXT FEW HOURS. THE COMBINATION OF THIS SNOW AND
FREEZING DRIZZLE WARRANTS A CONTINUATION OF THE ADVISORY. LUCKILY
IMPACTS SHOULD CONTINUE TO DECREASE AS ROADS CONTINUE TO BE
TREATED...THOUGH THE LOSS OF DAYTIME HEATING WILL ALLOW UNTREATED ROADS
TO COOL AND MAKE THINGS WORSE.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 331 PM CST MON JAN 26 2015
MAIN FORECAST PROBLEM WILL BE LINGERING FREEZING DRIZZLE
CHANCES THROUGH THIS EVENING.
SURFACE MAP THIS AFTERNOON HAS SURFACE LOW OVER THE ARROWHEAD WITH A
WARM FRONT EXTENDING ACROSS EASTERN MN/IA. TEMPERATURES RANGED FROM
THE MIDDLE 30S TO MIDDLE 40S BEHIND THE FRONT ACROSS SOUTHEAST
MN/NORTHEAST IA...TO THE LOWER TO MIDDLE 20S EAST OF THE MISSISSIPPI
RIVER/AHEAD OF THE FRONT. LOWER LEVEL ISENTROPIC LIFT ACROSS THIS
FRONT WAS PRODUCING AREAS OF FREEZING DRIZZLE EAST OF THE
MISSISSIPPI WITH REPORTS OF SOME SLIPPERY STRETCHES ON ROADWAYS VIA
WI 511 AND FROM LOCAL ROAD CREW.
LOOK FOR THE SURFACE LOW TO MOVE SOUTHEAST FROM THE ARROWHEAD OF MN
THIS AFTERNOON INTO NORTHWEST IL BY EARLY THIS EVENING. MAIN LIFT
AHEAD OF THIS LOW ...WHICH IS PRESENTLY CAUSING THE FREEZING DRIZZLE
WILL THEREFORE BE IN A WANING PHASE WITH ITS PASSAGE. HOWEVER...RAP
BUFKIT SOUNDING SHOWS SOME LINGERING LIFT ACROSS CENTRAL WI THROUGH
LATER THIS EVENING AS THE MID-LEVEL/SURFACE INVERTED TROUGH HANGS
UP. WILL THEREFORE CONTINUE TO CARRY FREEZING DRIZZLE MENTION INTO
THIS EVENING. THERE MAY BE SOME LIGHT SNOW AS WELL WITH POCKETS OF
FEEDER/SEEDER ICE. MAY HAVE TO EXTEND CURRENT ADVISORY A LITTLE
LONGER INTO THIS EVENING TO COVER FOR THIS. WILL KEEP A CLOSE EYE ON
IT.
HIGH PRESSURE BUILDS OVER THE AREA LATER TONIGHT THROUGH TUESDAY FOR
QUIET WEATHER. LOOKS LIKE IT WILL REMAIN MOSTLY CLOUDY THOUGH DESPITE
HIGH BUILDING IN DUE TO MOISTURE BEING TRAPPED UNDER THE SUBSIDENCE
INVERSION. WITH PARTIAL SUNSHINE LATE IN THE MORNING THROUGH THE
AFTERNOON...PLAN ON HIGHS REBOUNDING INTO THE 30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 331 PM CST MON JAN 26 2015
UNSEASONABLY MILD CONDITIONS EXPECTED FOR WEDNESDAY AHEAD OF
APPROACHING LOW PRESSURE ACROSS THE PLAINS. DESPITE AN INCREASE IN
STRATUS CLOUD...LOOK FOR HIGHS WELL INTO THE 30S WITH POSSIBLY A FEW
LOWER 40 READINGS ACROSS PARTS OF NORTHEAST IA INTO FAR SOUTHWEST WI.
A WINTRY MIX LOOKS TO IMPACT THE AREA WEDNESDAY NIGHT INTO THURSDAY
MORNING AS THE LOW OVER THE PLAINS MOVES TOWARD THE GREAT LAKES
REGION. MODEL SOUNDINGS NOT SHOWING A LOT OF ICE IN CLOUD FOR SNOW
PRODUCTION...SO LOOKS LIKE MORE OF A FREEZING RAIN/DRIZZLE POTENTIAL
AS A RESULT. WILL CONTINUE TO MONITOR THIS.
LATEST GFS/ECMWF SHOW ANOTHER STORM SYSTEM MOVING OUT OF THE PLAINS
TOWARD THE UPPER MISSISSIPPI RIVER REGION SATURDAY AFTERNOON INTO
SUNDAY FOR SNOW CHANCES.
OTHERWISE...LOOKS LIKE A SIGNIFICANT COOL DOWN THROUGH THE
WEEKEND/EARLY NEXT WEEK AS PATTERN SHIFTS TO NORTHWEST FLOW ALOFT.
HIGHS ON SATURDAY EXPECTED TO BE IN THE 20S...COOLING INTO THE
SINGLE DIGITS/TEENS BY MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 540 PM CST MON JAN 26 2015
A LOW PRESSURE TROUGH HAS STALLED OUT ALONG THE MISSISSIPPI RIVER.
WEST OF THE TROUGH AT RST...CEILINGS ARE VFR...BUT ALONG THE
TROUGH AT LSE CEILINGS ARE MVFR. THIS TROUGH IS EXPECTED TO REMAIN
IN PLACE THROUGH TUESDAY...HELPING TO MAINTAIN LOW STRATUS AND
POSSIBLY EVEN PRODUCE SOME -FZDZ AT LSE THIS EVENING. A WEAKENING
TREND TO THE TROUGH WILL HELP TO DIMINISH THE -FZDZ THREAT AFTER
MIDNIGHT. ADDITIONALLY...A COLD FRONT NORTH OF MSP IS FORECAST TO
DROP THROUGH RST THIS EVENING. THE COLDER AIR RUSHING INTO THE
MOIST AIRMASS IN PLACE SHOULD ALLOW CEILINGS TO FALL THROUGH THE
MVFR AND EVENTUALLY IFR RANGE BY TUESDAY MORNING. CEILINGS AT BOTH
TAF SITES SHOULD RISE GRADUALLY TUESDAY AFTERNOON AS THE TROUGH
WEAKENS AND DAYTIME MIXING ASSISTS.
NO VISIBILITY IMPACTS ARE EXPECTED THROUGH TUESDAY WITH ENOUGH
MIXING TAKING PLACE NEAR THE GROUND.
REGARDING WINDS...A 15 KT BREEZE CONTINUES AT RST...BUT SHOULD
GRADUALLY DIMINISH AND TURN NORTHERLY OVERNIGHT AS THE PRESSURE
GRADIENT WEAKENS. WITH THE TROUGH OVER LSE...LOOK FOR LIGHT WINDS
THERE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ017-
029-032>034-041>044-053>055-061.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 253 PM CST SUN JAN 25 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH
PRESSURE BUILDING SOUTHWARD OVER LAKE SUPERIOR EARLY THIS
AFTERNOON. A FEW POCKETS OF STRATO-CU REMAIN OVER THE FORECAST
AREA...BUT MAJORITY OF LOCATIONS HAVE CLEARED OUT. WILL SEE A SHORT
PERIOD OF MOSTLY CLEAR SKIES THIS AFTERNOON...THEN AN AREA OF
THINNING ALTO-CUMULUS WILL MOVE SOUTHEAST ACROSS NORTHERN
WISCONSIN. LOOKING FARTHER UPSTREAM...THE NEXT CLIPPER SYSTEM IS
MOVING SOUTHEAST INTO THE LAKE WINNIPEG REGION...AND POISED TO
ARRIVE LATE TONIGHT INTO MONDAY MORNING. SNOWFALL POTENTIAL WITH
THIS SYSTEM IS THE MAIN FORECAST CONCERN.
TONIGHT...LINGERING AREAS OF STRATO-CU OVER CENTRAL AND NORTHEAST
WISCONSIN WILL BE FADING BY SUNSET AS INCOMING ARCTIC HIGH AND VERY
DRY AIR OVERWHELM THE LOW LEVEL MOISTURE. POCKET OF MID-CLOUDS WILL
BE MOVING ACROSS THE FORECAST AREA AT THE START OF THE EVENING BUT
THINKING THESE CLOUDS WILL THIN/DIMINISH AS SUBSIDENCE INCREASES.
IF THIS OCCURS...THIS WILL LEAVE A FEW HOUR WINDOW FOR GOOD
RADIATIONAL COOLING OVER N-C WISCONSIN UNTIL CLOUDS INCREASE AGAIN
LATE IN THE EVENING. WILL DROP LOW TEMPS ACROSS N-C WISCONSIN AND
THEN SHOW RISING TEMPS AFTER MIDNIGHT. THE NEXT ALBERTA CLIPPER
WILL MAKE QUICK PROGRESS TONIGHT AND REACH THE BOUNDARY WATERS OF
NORTHERN MINNESOTA BY 12Z MON. WARM ADVECTION AHEAD OF THE CLIPPER
WILL CAUSE MID AND HIGH CLOUDS TO LOWER OVERNIGHT...WITH A CHANCE OF
SNOW ARRIVING OVER N-C WISCONSIN BETWEEN 09-12Z. UNCERTAINTY IS
RATHER HIGH WITH LOW TEMPS ACROSS N-C WISCONSIN...BUT WENT BELOW
GUIDANCE WITH LOWS RANGING FROM THE LOWER SINGLE DIGITS ABOVE ZERO
NORTH TO AROUND 10 ABOVE SOUTH.
MONDAY...LOW PRESSURE WILL CONTINUE TO MOVE SOUTHEAST AND WEAKEN AS
IT MOVES INTO NORTHWEST WISCONSIN BY 00Z. DECENT MID-LEVEL FGEN WILL
ACCOMPANY THE WARM ADVECTION OVER CENTRAL WISCONSIN DURING THE
MORNING BUT WILL GRADUALLY WEAKEN AS IT MOVES INTO EASTERN WISCONSIN
IN THE AFTERNOON. WITH SNOW RATIOS AROUND 15 TO 1...NORTH-CENTRAL
AND CENTRAL WISCONSIN COULD SEE AROUND 2 INCHES OF ACCUMULATION BY
THE END OF THE DAY WHILE EASTERN WISCONSIN SHOULD SEE AROUND AN INCH
OR LESS. THE SNOW MAY ALSO MIX WITH FREEZING DRIZZLE OVER CENTRAL
WISCONSIN BY LATE IN THE AFTERNOON AS MID-LEVEL MOISTURE BEGINS TO
PEEL OUT. WILL INCREASE PRECIP CHANCES SUBSTANTIALLY. HIGHS
RETURNING TO THE 20S AS WINDS SHIFT TO THE SOUTH.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 253 PM CST SUN JAN 25 2015
NORTHWEST UPPER FLOW WILL CONTINUE THOUGH AT LEAST
THE END OF THIS WEEK. WEAK CLIPPER SYSTEMS WILL MOVE THROUGH
MONDAY NIGHT AND AGAIN WEDNESDAY NIGHT AND THURSDAY AND AGAIN
SATURDAY. THE MIDWEEK CLIPPER SYSTEM PROBABLY HAS THE BEST CHANCE
OF PRODUCING MORE THAN AN INCH OR TWO OF SNOW DEPENDING ON HOW
MUCH PHASING THERE IS WITH SOUTHERN STREAM JET ENERGY PASSING BY
TO THE SOUTH.
THERE IS ALSO LIMITED MOISTURE WITH ALL THREE SYSTEMS SO DO NOT
EXPECT ANY BIG SNOWS THIS WEEK. UPPER HEIGHTS BUILD THROUGH MID
WEEK DESPITE THE FLOW BEING NORTHWEST. THIS SHOULD RESULT IN ABOVE
NORMAL TEMPERATURES. COLDER AIR WILL ARRIVE LATER THIS WEEK WITH
THE POSSIBILITY OF REAL ARCTIC AIR SUNDAY OR MONDAY OF THE
FOLLOWING WEEK.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1124 AM CST SUN JAN 25 2015
LOW STRATUS AND FLURRY ACTIVITY AS BEEN PERSISTENT SO FAR THIS
MORNING...BUT DRY AIR FROM THE LARGE ARCTIC AIR IS STARTING TO MAKE
INROADS OVER NORTHERN LAKE MICHIGAN. BREAKS IN THE CLOUDS ARE ALSO
DEVELOPING OVER NORTHERN WISCONSIN. ANTICIPATE THESE TRENDS TO
CONTINUE THIS AFTERNOON AS THE ARCTIC HIGH MOVES SOUTH OVER LAKE
SUPERIOR...AND SKY CONDITIONS TO TURN VFR BY MID TO LATE AFTERNOON.
GUSTY NORTHEAST WINDS WILL ALSO DIMINISH LATER THIS AFTERNOON AS
WELL.
AFTER A PERIOD OF PARTLY CLOUDY AND VFR CONDITIONS...EXPECT MID AND
HIGH CLOUDS TO INCREASE AGAIN LATER THIS EVENING AHEAD OF THE NEXT
CLIPPER. SNOW FROM THE CLIPPER TO ARRIVE MONDAY MORNING OVER
NORTH-CENTRAL WISCONSIN...WHICH WILL DROP VSBYS TO IFR AND CIGS TO
AT LEAST LOW MVFR. THE SNOW IS EXPECTED TO REACH EASTERN WISCONSIN
AROUND MIDDAY. AN INCH OR TWO WILL BE POSSIBLE BY LATE MONDAY
AFTERNOON.
MPC.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1039 PM CST SAT JAN 24 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 250 PM CST SAT JAN 24 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SOUTHWARD
MOVING ARCTIC COLD FRONT REACHING THE U.P. BORDER EARLY THIS
AFTERNOON. BEHIND THIS FRONT IS A VERY COLD/DRY AIRMASS AS EVIDENT
BY TEMPS ONLY IN THE SINGLE DIGITS AND DEWPOINTS BELOW ZERO OVER ONTARIO.
THE FRONT IS MAINLY INACTIVE AT THE MOMENT. WEAK SHORTWAVE ACTIVITY
COMBINED WITH UPPER DIVERGENCE IS CONTRIBUTING TO SCATTERED SNOW
SHOWERS AND FLURRIES THAT ARE MOVING ACROSS NORTHWEST AND
NORTH-CENTRAL WISCONSIN. EXPECTATION IS THAT THESE LIGHT SNOW
SHOWERS WILL GRADUALLY DROP SOUTH INTO CENTRAL AND EAST-CENTRAL
WISCONSIN LATER THIS AFTERNOON. FARTHER WEST...A CLIPPER SYSTEM IS
DROPPING SOUTHEAST ACROSS THE NORTHERN PLAINS WITH A DECENT SWATH OF
SNOW OCCURRING OVER NORTH DAKOTA. SNOWFALL POTENTIAL ALONG THE
FRONT AND FROM THE CLIPPER ARE THE MAIN FORECAST CONCERNS.
TONIGHT...AN ARCTIC COLD FRONT WILL BE DROPPING SOUTH ACROSS THE
AREA THIS EVENING WHILE A CLIPPER TRACKS SOUTHEAST ACROSS THE
CENTRAL PLAINS AND INTO THE CENTRAL MISSISSIPPI VALLEY. PERHAPS
COULD SEE A FEW FLURRIES ALONG THE FRONT OVER FAR NORTHERN WISCONSIN
EARLY THIS EVENING...BUT ANTICIPATING BETTER CHANCES OF SNOW TO
OCCUR ALONG THE FRONT AS IT MOVES INTO CENTRAL WISCONSIN AND THE FOX
VALLEY BY MID-EVENING. GUIDANCE IS INDICATING DECENT MID-LEVEL FGEN
DEVELOPING ALONG THE FRONT IN ADDITION TO INCREASING LARGE SCALE
FORCING AHEAD OF THE SHORTWAVE. AS A RESULT...KEPT LOW CHANCE
POPS IN THE FORECAST THERE. STILL ANTICIPATING A GLANCING BLOW FROM
THE CLIPPER SYSTEM AFTER MIDNIGHT...THOUGH THE LATEST RUNS OF
MESOMODELS SUGGEST THE SNOW WILL MISS THE FORECAST AREA ENTIRELY.
AREAS FROM WISC RAPIDS TO WAUTOMA COULD SEE UP TO A HALF INCH...BUT
AMOUNTS WILL BE LESS FARTHER NORTH. WITH THE PASSAGE OF THE
FRONT...NORTHEAST WINDS WILL BECOME GUSTY OVER THE FOX VALLEY AND
LAKESHORE. WOULD NOT BE SURPRISED TO SEE A FEW GUSTS UP TO 30 MPH.
LOWS FALLING INTO THE UPPER SINGLE DIGITS IN THE FAR NORTH...TO THE
LOWER 20S IN THE SOUTH.
SUNDAY...A SMALL CHANCE OF SNOW WILL LINGER FROM WAUTOMA TO
MANITOWOC EARLY IN THE MORNING...BUT ANY SNOW SHOULD BE DEPARTING
QUICKLY AS THE CLIPPER MOVES TOWARDS THE OHIO VALLEY. MEANWHILE
ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST OVER LAKE SUPERIOR.
THIS ARCTIC HIGH WILL BRING A VERY DRY AIRMASS INTO THE NORTHERN
PART OF THE STATE (DEWPOINTS OVER ONTARIO ARE BELOW 0F). EVEN
THOUGH TEMPS WILL BE UNSTABLE OVER LAKE SUPERIOR AND
MICHIGAN...EXPECT THIS DRY AIR TO ERODE THE CLOUD COVER AS LAKE
EFFECT STREAMERS BECOME RETREAT CLOSER TO THE SHORELINES. THINK ITS
POSSIBLE TO SEE SOME SUN IN THE AFTERNOON AS A RESULT. TEMPS WILL
FALL BACK INTO THE MIDDLE TEENS TO LOWER 20S.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 250 PM CST SAT JAN 24 2015
WEAKENING CLIPPER SYSTEM SHOULD BRING LIGHT SNOW FOR
MONDAY THROUGH MONDAY EVENING. AN INCH OR LESS LIKELY IN MOST PLACES.
A BETTER CHANCE OF ACCUMULATING SNOW WEDNESDAY NIGHT AND THURSDAY
AS A CLIPPER SYSTEM AND ONE MOVING EAST FROM THE CENTRAL PLAINS
PHASE JUST TO OUR SOUTH. SHOULD BE ABLE TO GET A FEW INCHES DESPITE
MEAGER MOISTURE. VERY COLD AIR LOOKS LIKELY EARLY NEXT WEEK. SUBZERO
HIGH TEMPERATURES AND WIND CHILLS OF 30 BELOW POSSIBLE NEXT MONDAY
AND TUESDAY IF GFS AND ECMWF FORECASTS ARE CORRECT.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1037 PM CST SAT JAN 24 2015
COLD FRONT WL FINISH DROPPING SWD ACRS AREA OVERNIGHT. THE FRONT
WL BE FOLLOWED BY MAINLY FLURRIES...BUT A FEW SHSN POSSIBLE S OF
AUW AND NEAR MTW. FLOW ACRS LAKES MICHIGAN/SUPERIOR WL KEEP MVFR
CIGS IN PLACE FOR A WHILE...BUT INCOMING AIR MASS IS VERY DRY...SO
STILL EXPECT CLDS TO DISSIPATE TOMORROW.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
400 AM MST SUN JAN 25 2015
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 1257 AM MST SUN JAN 25 2015
A WELL-DEFINED MID LEVEL SHORTWAVE CONTINUES TO DIVE QUICKLY ACROSS
THE CENTRAL PLAINS EARLY THIS MORNING. THIS SYSTEM WAS RESPONSIBLE
FOR SCATTERED RAIN AND/OR SNOW SHOWERS ACROSS MUCH OF SOUTHEAST WY
AND THE WESTERN NE PANHANDLE LAST EVENING. HOWEVER...LATEST TRENDS
IN RADAR/SAT IMAGERY INDICATE THIS ACTIVITY HAS GREATLY DIMINISHED
IN COVERAGE AS OF 08Z OWING TO INCREASING SUBSIDENCE IN THE WAKE OF
THE DEPARTING WAVE. WE ARE STILL SEEING A FEW WEAK ECHOS FROM KCYS
ALONG THE WY/NE STATE LINE NEAR SCOTTSBLUFF...BUT POTENTIAL FOR ANY
MEASURABLE PCPN IS UNLIKELY WITH DRYING LOW LEVELS AND LARGER SCALE
SINKING MOTION OVERSPREADING THE AREA. LLVL GRADIENTS STAY ELEVATED
TODAY WITH AROUND 50 METERS BETWEEN CAG-CPR AT H85. FAST NORTHWEST
FLOW ALOFT PERSISTS WITH A 130 KT H25 JET OVER EASTERN MT/WY...SO
THE WIND PRONE AREAS WILL UNDOUBTEDLY BE QUITE WINDY. A FEW WYDOT
SENSORS NEAR ARLINGTON HAVE RECORDED WINDS NEAR 50 MPH IN THE LAST
COUPLE OF HOURS...BUT DO NOT EXPECT WARNING CRITERIA GUSTS AS THE
MODELS SUGGEST WEAKENING FLOW ALOFT WITH TIME. A PRETTY UNEVENTFUL
SHORT TERM PERIOD ASIDE FROM BREEZY CONDITIONS TODAY. GFS/NAM/ECM
ARE IN EXCELLENT AGREEMENT WITH BROAD UPPER-LEVEL RIDGING BECOMING
ESTABLISHED ON MON/TUE. H7 TEMPS ARE PROGGED TO BE AROUND 5-7 DEG C
AT 00Z TUE. NO REAL CONCERNS ABOUT CIRRUS EITHER WITH FAIRLY DRY RH
PROGS BETWEEN H2-H3 PER THE GFS. ADIABATIC WARMING IS LIKELY WITH
GOOD SUBSIDENCE AND WESTERLY LLVL DOWNSLOPE...SO TEND TO FAVOR THE
WARMER MOS WITH HIGHS AROUND 65 F OVER THE PLAINS. COULD SEE A FEW
RECORDS THREATENED EARLY IN THE WORK WEEK. PCPN CHANCES WILL BE ON
THE INCREASE OVER THE FAR SOUTHWEST ON TUE NIGHT AHEAD OF A STRONG
SHORTWAVE LIFTING ACROSS CENTRAL UTAH.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 300 AM MST SUN JAN 25 2015
UPPER RIDGE THAT GAVE US THE WARM TEMPERATURES STILL FORECAST TO
MOVE INTO EASTERN NEBRASKA WEDNESDAY MORNING. SHORTWAVE TROUGH
MOVES THROUGH WYOMING WEDNESDAY AFTERNOON FOR A RETURN OF COLDER
TEMPERATURES AND MOUNTAIN SNOW. BY WEDNESDAY AFTERNOON...GFS 700MB
TEMPERATURES FALL TO -6C...DOWN FROM +4C TUESDAY AFTERNOON.
GOING TO BE WINDY WITH THE ASSOCIATED COLD FRONT MOVING THROUGH
WEDNESDAY. GFS 700MB WINDS 45 TO 50KTS...SO LIKELY TO SEE WIND
HEADLINES FOR THE WIND PRONE AREAS. ABOUT .3 TO .4 INCHES QPF FOR
THE MOUNTAINS OUT WEST WITH THIS SYSTEM...SO COULD SEE ADVISORY
LEVEL SNOW AMOUNTS FOR THE SNOWY AND SIERRA MADRE RANGES.
ANOTHER WEAK SYSTEM FOR FRIDAY THAT WILL BRING SOME MORE LIGHT
SNOW AMOUNTS FOR THE MOUNTAINS. MOST EVERYWHERE ELSE SHOULD STAY
DRY WITH THIS SYSTEM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 357 AM MST SUN JAN 25 2015
LATEST HRRR GUIDANCE FOR THE 12Z TAFS. LATEST 11-3.9U SATELLITE
IMAGERY SHOWS WIDESPREAD STRATUS OUT BY KRWL THIS MORNING. HRRR
SHOWS THE POTENTIAL FOR THIS STRATUS TO HANG IN AROUND KRWL FOR
MOST OF THE DAY. SOME BREAK UP BY MID MORNING SHOWN...SO WENT
SCT008 AFTER 15Z. VFR CONDITIONS ELSEWHERE.
&&
.FIRE WEATHER...
ISSUED AT 1257 AM MST SUN JAN 25 2015
NO MAJOR FIRE WEATHER CONCERNS. WARM TEMPERATURES AND LOCALLY BREEZY
CONDITIONS ARE LIKELY THROUGH MONDAY AFTERNOON. ALL PARAMETERS ARE
EXPECTED TO BE WELL BELOW CRITICAL THRESHOLDS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...CLH
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
336 AM CST TUE JAN 27 2015
.SHORT TERM...
330 AM CST
THROUGH WEDNESDAY...
INFRARED AND WATER VAPOR SATELLITE LOOPS EARLY THIS MORNING HAVE
SHOWN THE LAST IN A SERIES OF SHEARED VORTICITY MAXIMA TO HAVE MOVED
SOUTHEAST OF THE AREA. LIGHT SNOW ASSOCIATED WITH THESE HAS MAINLY
ENDED. LOW-LEVEL WINDS HAVE ALSO SHIFTED MORE NORTHERLY AS A
SURFACE INDUCED TROUGH AXIS PULLS AWAY. THIS HAS ENDED THE LOW-
LEVEL ISENTROPIC ASCENT AND OMEGA WHICH HELPED TO INDUCE MUCH OF
THE FREEZING DRIZZLE LAST NIGHT. SO WITH THAT HAVE CANCELLED THE
ADVISORY AS THE WIDESPREAD THREAT HAS ENDED GOING INTO THE RUSH
HOUR. ONE HOPEFULLY ONLY SMALL FLY IN THE OINTMENT TO THIS IS THE
CHANCE FOR FREEZING DRIZZLE LINGERING IN MAINLY LAKE AND COOK
COUNTIES...INCLUDING CHICAGO...AS WINDS TURN OFF THE LAKE EARLY
THIS MORNING STEERING IN SOME MARGINAL LAKE-INDUCED INSTABILITY.
THE MKX RADAR IS INDICATING LIGHT ECHOES MOVING WESTWARD THAT
DUAL-POL SUGGESTS IS FREEZING DRIZZLE. RAP PROFILES ARE ONLY
SATURATED ABOUT AS COOL AS -8C ADDING SUPPORT TO THAT. WITH NOT
EXPECTING A SITUATION SUCH AS LAST EVENING GIVEN THE TREATMENT ON
ROADS AND THE DIFFERENT MORE MESOSCALE/LOCALIZED INDUCED
LIFT...FEEL BETTER GOING WITH AN SPS IF NEEDED. EXPECT THE CHANCES
TO END BY 10 AM OR SO AS DRIER AIR CONTINUES TO ADVECT WESTWARD
OVER THE LAKE SEEN BY DEW POINTS NEAR 10F ON THE MICHIGAN SHORE
ALONG WITH AN EAST WIND.
CLOUDS SHOULD BE SLOW TO CLEAR TODAY GIVEN THE CURRENT EXPANSIVENESS
TO THE NORTH AND THE CYCLONIC FLOW CONTINUING THROUGH THIS
MORNING...AS WELL AS AFOREMENTIONED LAKE-ORIENTED FLOW INTO
NORTHEAST ILLINOIS. MESOSCALE MODEL MOISTURE/CONDENSATE FIELDS
INDICATE CLOUDS LINGERING THE LONGEST ACROSS THE ILLINOIS PART OF
THE CWA WITH INDIANA EXPERIENCING NORTHEASTERLY DRY ADVECTION.
HAVE HIGHS ONLY A FEW DEGREES WARMER THAN CURRENT EARLY MORNING
VALUES GIVEN THIS THOUGHT PROCESS. CONFIDENCE IS LOW ON WHETHER
CLEARING OCCURS AREAWIDE LATE THIS AFTERNOON AND EVENING AS
GUIDANCE WOULD SUGGEST...PLUS THERE WILL LIKELY BE CIRRUS
SPREADING IN TOO. THIS INTRODUCES BUST POTENTIAL IN LOW
TEMPERATURES OVER NORTH CENTRAL ILLINOIS WHERE LOW TEENS TO MID
20S COULD OCCUR DEPENDING ON CLOUDS. FEEL MORE CONFIDENT NORTHWEST
INDIANA WILL BE MOSTLY CLEAR AND TOUCH SOME OF THOSE LOWER TO MID
TEENS.
DURING THE DAY WEDNESDAY...A THERMAL RIDGE BUILDS INTO THE AREA AND
EXPECTING AT LEAST SOME SUNSHINE AS SOUTHWESTERLY LOW-LEVEL FLOW
WILL BE ENOUGH TO ADVECT OUT ANY RESIDUAL LOW CLOUDS. THE WARMEST
PART OF THE THERMAL RIDGE REACHES US MORE SO WEDNESDAY NIGHT AND
CLIMATOLOGY FOR FORECAST 925MB TEMPERATURES WOULD KEEP
SURFACE READINGS IN THE 30S FOR MOST OF THE CWA ESPECIALLY WITH
SOME SNOW COVER ALBEIT MINIMAL.
MTF
&&
.LONG TERM...
330 AM CST
WEDNESDAY NIGHT THROUGH MONDAY...
THE NEXT CHANCE FOR PRECIPITATION IS WEDNESDAY NIGHT AND
THURSDAY...AND CONFIDENCE HAS FURTHER INCREASED THAT THIS WILL BE A
LIGHT PRECIPITATION EVENT...AS WELL AS ONE WITH ONLY LIQUID
WEDNESDAY NIGHT IF PRECIPITATION DEVELOPS OVER OUR AREA. A CLOSED
UPPER LOW NEAR LOS ANGELES EARLY THIS MORNING IS STILL FORECAST TO
GET CAUGHT IN THE WESTERLIES AND DAMPEN THE STRONG UPPER RIDGE IN
PLACE OVER THE ROCKIES. A GRADUAL PHASING WITH A NORTHERN STREAM
PROGRESSIVE WAVE IS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY
OVER THE GREAT LAKES REGION. WHILE THE 27.00 GFS IS MORE
AGGRESSIVE WITH THIS PHASING THAN OTHER 27.00 GUIDANCE...IT ONLY
BRINGS A LITTLE MORE OOMPH FOR PRECIP HERE. THE THERMAL RIDGE
MENTIONED IN THE SHORT TERM SECTION FOR WEDNESDAY IS 2C-6C AT
850-925MB AND SURFACE TEMPERATURES ARE NOT LIKELY TO DROP GIVEN
THE SOUTHERN FLOW AND INCREASING CLOUDS...SO HAVE CHANCES OF RAIN
AND DRIZZLE WEDNESDAY NIGHT AS MOISTURE TRANSPORT DEVELOPS. ON
THURSDAY...TRANSITION TO A LIGHT RAIN AND SNOW MIX AND AT THIS
POINT WPC AND OURSELVES REALLY HAVE NO ACCUMULATIONS FORECAST.
HAVE STILL TRIED TO TAKE INTO ACCOUNT SOME POSSIBLE SLOWING IN THE
FORECAST GIVEN THE CURRENT SIGNIFICANT CLOSED SYSTEM OFF THE
NORTHEAST U.S...AND KEPT PRECIP CHANCES INTO THURSDAY AFTERNOON.
THE PROGRESSIVE ACTIVE FLOW PATTERN IS FORECAST TO CONTINUE INTO
THE WEEKEND...WITH STRONG HIGH PRESSURE ON FRIDAY GIVING WAY TO
PRECIPITATION CHANCES THIS WEEKEND. ANOTHER CLOSED LOW OVER THE
FAR SOUTHWESTERN U.S. IS FORECAST TO MOVE GRADUALLY EASTWARD AND
LOOKS TO BE ABLE TO TAP INTO GULF AND EASTERN PACIFIC MOISTURE.
WITH A CUT-OFF FEATURE THIS COULD END UP SLOWING AND CERTAINLY
CHANGING IN EVOLUTION. GUIDANCE DISAGREES HOW ANY NORTHERN STREAM
DISTURBANCE MAY AID TO PULL SOME OF THIS MOISTURE OVER OUR AREA.
AT THIS TIME THIS LOOKS TO BE A POSSIBLY LONG DURATION BUT LIGHT
INTENSITY QPF EVENT AT THIS LATITUDE. GIVEN THE FEATURES AT PLAY
AND CURRENT PATTERN WE ARE IN...ITS JUST WAY TOO EARLY AS
POTENTIAL COULD GO EITHER WAY FROM THAT SOLUTION. CONFIDENCE IS A
LITTLE HIGHER IN THAT IT WOULD PROBABLY BE A MAINLY SNOW EVENT IF
IT WERE TO OCCUR. GUIDANCE IS IN BETTER AGREEMENT THAN 24 HOURS
AGO WITH A CANADIAN/MODIFIED ARCTIC AIR MASS BEING TAPPED IN THE
WAKE OF THIS SYSTEM WITH POSSIBLY SINGLE DIGIT NIGHTTIME
TEMPERATURES DEPENDING ON IF ANY FRESH SNOW COVER CAN OCCUR.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* LOW-MVFR/OCCASIONALLY HIGH-IFR CIG EARLY THIS MORNING. SPOTTY
LIGHT FREEZING DRIZZLE ALSO POSSIBLE THROUGH SUNRISE.
* CIGS EXPECTED TO IMPROVE TO SOLID MID-HIGH RANGE MVFR AFTER
SUNRISE...SCATTERING TO VFR BY MID-AFTERNOON.
* LIGHT NORTH-NORTHEAST WINDS...BECOMING NORTHEAST AND INCREASING
TO AROUND 10 KT DURING THE DAY.
RATZER
//DISCUSSION...UPDATED 09Z...
MID-LEVEL DISTURBANCE MOVING THROUGH WITH TRAILING EDGE OF MORE
ORGANIZED LIGHT SNOW NOW EXITING TO THE SOUTHEAST. WEAK CONVERGENT
LOW LEVEL WIND FIELD MAY STILL ALLOW FOR A LITTLE PATCHY LIGHT
FREEZING DRIZZLE FOR THE NEXT FEW HOURS GIVEN SATURATED LOW
LEVELS. CIGS HIGH-END IFR OR LOW-END MVFR SHOULD SHOW A GRADUAL
RISING TREND AS DRIER AIR SLOWLY ARRIVES FROM THE NORTHEAST.
RATZER
PREVIOUS DISCUSSION FROM 06Z...
ELONGATED/SHEARED MID-LEVEL DISTURBANCE CONTINUES TO PROPAGATE
SOUTHEASTWARD ACROSS THE FORECAST AREA AT MIDNIGHT...PRODUCING AN
AREA OF LIGHT SNOW AND SOME FREEZING DRIZZLE ACROSS SOUTHEAST
WISCONSIN AND NORTHEAST IL/NORTHWEST INDIANA. EXTRAPOLATION OF
RADAR FEATURES...WHICH COINCIDES WITH IR COLDER CLOUD TOPS AND AND
MODEL FORECAST OF SHEARED MID-LEVEL CIRCULATION...SUGGESTS MORE
ORGANIZED PRECIPITATION SHOULD END BY 10Z OR SO FOR THE CHICAGO
TERMINALS AND A COUPLE OF HOURS EARLIER FOR RFD. FORECAST
SOUNDINGS DO DEPICT LOW LEVELS REMAINING VERY MOIST AND CAPABLE OF
PRODUCING LIGHT FREEZING DRIZZLE/FLURRIES (SNIZZLE) AND AT LEAST
PATCHY IFR CIGS THROUGH SUNRISE OR SO...BEFORE INCREASING NORTH-
NORTHEAST BOUNDARY LAYER WINDS REALLY BEGIN TO DRY OUT THE LOWER
LEVELS. CONCURRENT WITH THAT...THERE SHOULD BE A STEADY
IMPROVEMENT IN CIG/VIS AND EVENTUALLY SCATTERING TO VFR IS
EXPECTED BY EARLY-MID AFTERNOON.
AS FOR WINDS...WEAK SURFACE LOW/TROUGH ACROSS IL WILL MOVE OFF TO
THE SOUTHEAST ACROSS THE OHIO RIVER THIS MORNING...ALLOWING LIGHT
SOUTHEAST (OR CALM/VARIABLE AT RFD) WINDS TO BACK TO THE NORTHEAST
AND EVENTUALLY INCREASE TO AROUND 10 KT LATER THIS MORNING. WEAK
HIGH PRESSURE RIDGE THEN MOVES INTO THE REGION TONIGHT ALLOWING
LIGHT WINDS TO VEER TO THE SOUTHEAST AGAIN.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 09...
* HIGH IN ANY -FZDZ BEING LIGHT EARLY THIS AM.
* HIGH IN WIND TRENDS.
* MEDIUM WITH CIG/VIS TRENDS REMAINDER OF OVERNIGHT/EARLY MORNING
HOURS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...VFR THEN CHANCE FOR LIGHT RAIN OR DRIZZLE WEDNESDAY
NIGHT AND POTENTIAL FOR MVFR/IFR.
THURSDAY...CHANCE OF LIGHT SNOW OR LIGHT RAIN/SNOW MIX/ MVFR
LIKELY/IFR POSSIBLE.
FRIDAY...NORTH WINDS. PRIMARILY VFR.
SATURDAY AND SUNDAY...CHANCE OF LIGHT SNOW SATURDAY NIGHT INTO
SUNDAY. IFR POSSIBLE.
RC
&&
.MARINE...
213 AM CST
MARINE CONCERNS ON LAKE MICHIGAN ARE A PERIOD OF STRONG SOUTH WINDS
WEDNESDAY AFTERNOON AND NIGHT...THEN A SHIFT TO STRONG NORTH TO
NORTHWEST WINDS THURSDAY AFTERNOON INTO EARLY FRIDAY...WITH THE
POTENTIAL FOR A PERIOD OF NORTHWEST GALES ESPECIALLY THURSDAY
AFTERNOON AND THURSDAY EVENING.
IN THE NEAR TERM...RELATIVELY QUIET WEATHER ACROSS THE LAKE EARLY
THIS MORNING AS A WEAKENING SURFACE TROUGH OVER ILLINOIS AND THE
LOWER OHIO VALLEY CONTINUES TO MOVE OFF TO THE SOUTHEAST...ALLOWING
WEAK HIGH PRESSURE TO SETTLE ACROSS THE AREA FROM THE NORTH TODAY.
LOOKING TO THE WEST...AN AREA OF LOW PRESSURE DEVELOPING IN THE LEE
OF THE CANADIAN ROCKIES WILL SLIDE SOUTHEAST INTO THE PLAINS
THROUGH TONIGHT...THEN WILL MOVE SLOWLY EAST TOWARD LAKE MICHIGAN
WEDNESDAY AND WEDNESDAY NIGHT. IN RESPONSE TO PRESSURE FALLS AHEAD
OF THE LOW...THE GRADIENT WILL TIGHTEN ACROSS LAKE MICHIGAN
WEDNESDAY WITH SOUTH WINDS RAMPING UP INTO THE 30 KT RANGE BY LATE
AFTERNOON AND EVENING. WINDS WILL DIMINISH BRIEFLY EARLY THURSDAY
MORNING AS THE LOW PRESSURE CENTER AND COLD FRONTAL TROUGH CROSS THE
LAKE...BEFORE WINDS SHIFT TO THE NORTH-NORTHWEST AND INCREASE
QUICKLY BACK INTO THE 30-35 KT RANGE THURSDAY AFTERNOON. FORECAST
SOUNDINGS INDICATE THE POTENTIAL FOR GALES THURSDAY AFTERNOON AND
EVENING IN THE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND THE
DEPARTING LOW AND COLD FRONT. THESE STRONG WINDS WILL CONTINUE INTO
EARLY FRIDAY...BEFORE DIMINISHING AS A BROAD AREA OF HIGH PRESSURE
SPREADS INTO THE AREA BY FRIDAY EVENING. THE HIGH WILL SLOWLY MOVE
OFF TO THE EAST ON SATURDAY...WITH A WEAK LOW EXPECTED TO PASS
ACROSS THE NORTHERN LAKES SATURDAY NIGHT AND TRAIL A COLD FRONT
ACROSS LAKE MICHIGAN THROUGH SUNDAY.
FOR THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE WATERS SMALL CRAFT
ADVISORY CONDITIONS LOOK TO DEVELOP WEDNESDAY AFTERNOON AND CONTINUE
THROUGH THURSDAY MORNING...WITH A BRIEF BREAK BEFORE HIGH WIND/WAVE
CONDITIONS DEVELOP AGAIN BY EARLY THURSDAY AFTERNOON. HIGH WAVES
WOULD LIKELY LINGER THROUGH MUCH OF FRIDAY...ESPECIALLY ALONG THE
INDIANA SHORE EAST OF GARY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FREEZING RAIN ADVISORY...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 6 AM
TUESDAY.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
412 AM EST TUE JAN 27 2015
.SYNOPSIS...
ISSUED AT 410 AM EST TUE JAN 27 2015
SOME VERY LIGHT SNOW OR LIGHT FREEZING DRIZZLE WILL BE POSSIBLE
EARLY THIS MORNING ACROSS FAR WESTERN AND NORTHWESTERN INDIANA AS
WELL AS ILLINOIS. ANY PRECIPITATION IS EXPECTED TO DIMINISH
SHORTLY AFTER SUNRISE. HIGHS TODAY WILL BE IN THE UPPER 20S AND
30S WITH PARTLY TO MOSTLY CLOUDY SKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM EST TUE JAN 27 2015
ANOTHER RELATIVELY QUIET SHORT TERM BUT CLOUD CONCERNS AND POSSIBLE
FZDZ THIS MORNING MAKE FOR A FEW ISSUES. FAR WESTERN CWA SATURATED
OVERNIGHT WITH FLURRIES OR VERY LIGHT SNOW FALLING IN DOWNSHEAR SIDE
OF MID LEVEL JET AXIS. ADVISORY ISSUED LAST EVENING FOR FREEZING
DRIZZLE THAT NEVER REALLY MATERIALIZED OVER OUR AREA DUE TO
SATURATED DGZ AND SEEDER FEEDER MECHANISMS ALLOWING FOR SNOW CRYSTAL
GROWTH. HOWEVER...STILL A SLIGHT CONCERN FOR LIGHT FZDZ THROUGH
SUNRISE AS SATELLITE SHOWS WARMING CLOUD TOPS UPSTREAM ACROSS WI
MOVING QUICKLY SOUTH AND LOSS OF HIGHER SEED CLOUDS EXPECTED NEXT
FEW HOURS. HIRES MODEL SOUNDINGS INDEED SHOWING DGZ DRYING OUT EARLY
THIS MORNING IN THE WEST BUT LOW LEVELS ALSO DRYING. THUS CHANCES
FOR ANY PCPN WILL BE DIMINISHING BUT PCPN TYPE OF ANY RESIDUAL PCPN
COULD BE FZDZ. CALLS TO WHITE AND PULASKI COUNTY INDICATE NO
PROBLEMS FROM FZDZ OVERNIGHT AND LITTLE TO NO REPORTS OF FZDZ
UPSTREAM AT THIS HOUR. WITH ADVISORY SET TO EXPIRE AT 6AM ANYWAY
PLAN TO CANCEL EARLY AND HANDLE ANY SPOTTY FREEZING LIQUID
DEVELOPMENT WITH SPECIAL WEATHER STATEMENTS IF NEEDED.
DRY WEDGE IN LOWER LEVELS HAS REMAINED IN PLACE ACROSS REMAINDER OF
CWA WITH LIGHT EASTERLY FLOW AIDING IN DRY AIR ENTRAINMENT. THIS DRY
EASTERLY FLOW ALONG WITH SUBSIDENCE TODAY EXPECTED TO HELP BREAK UP
CLOUDS FROM NORTHEAST TO SOUTHWEST THROUGH THE DAY.
HOWEVER...SATELLITE SHOWS AREA OF STRATUS OVER WI MOVING SLOWLY
SOUTHWARD AND MODELS DO NOT HAVE A GOOD HANDLE ON THIS CLOUD COVER.
LOW LEVEL RH PROGS FROM VARIOUS MODELS ALL SEEM TO SUPPORT DRYING
TODAY FROM THE NORTHEAST BUT RUC13 HAS ALSO SHOWN A TENDENCY FOR
HIGHER RH ACROSS CENTRAL OH TO ADVECT WEST INTO OUR EASTERN AREA
THIS AFTERNOON. ALL THESE CLOUD ISSUES MAKE FOR DIFFICULT FORECAST
TODAY. MOST SURROUNDING OFFICES FAVORING THE CLEARING SCENARIO SO
WILL LEAN TOWARD THE DRYING AND BE OPTIMISTIC WITH SKIES BECOMING
PARTLY CLOUDY AND EVENTUALLY MOSTLY CLEAR TONIGHT. HIGH PRESSURE TO
THEN SLIDE ACROSS THE AREA TONIGHT WITH LIGHT WINDS AND MOSTLY CLEAR
SKIES. THIS SHOULD ALLOW GOOD RADIATIONAL COOLING AND TEMPS TO DROP
BACK TO SINGLE DIGITS EASTERN HALF AND LOWER TEENS WEST WHERE SOME
MID AND HIGH CLOUDS MAY SPILL OVER RIDGE.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM EST TUE JAN 27 2015
NEXT CLIPPER-TYPE SYSTEM STILL SLATED TO IMPACT THE AREA LATE
WEDNESDAY NIGHT INTO THURSDAY. THIS WAVE WILL ACTUALLY BE AIDED TO
SOME DEGREE BY ANOTHER VORT MAX LEFTOVER FROM OLD BAJA CUTOFF LOW
CURRENTLY BEING REABSORBED INTO THE MEAN WESTERLIES. STILL SOME
INCONSISTENCIES IN THE MODELS REGARDING WHERE EXACTLY THESE TWO
WAVES TRACK AND HOW THEY INTERACT BUT OUR AREA SHOULD SEE A PERIOD
OF DECENT PV ADVECTION/CVA THAT WILL GENERATE AT LEAST SOME FORCED
ASCENT AND LIGHT PRECIP. THE PROBLEM IS THAT UPPER JET SUPPORT IS
MARGINAL AT BEST AND LATEST CONSENSUS TRACK FORECAST KEEPS THE BEST
LOW LEVEL ISENTROPIC ASCENT AND FRONTOGENESIS GENERALLY NORTH OF OUR
AREA. FURTHERMORE...STRONG LOW LEVEL WAA WILL INTRODUCE A MELTING
LAYER ALOFT (AND EVENTUALLY AT THE SURFACE) THAT WILL MAKE
ACCUMULATING SNOW VERY DIFFICULT WITH A HODGEPODGE OF ALL DIFFERENT
PRECIP TYPES OVER SPACE AND TIME. IMPOSSIBLE TO CORRECTLY NAIL DOWN
EXACT TIMING AND LOCATION OF VARIOUS PRECIP TYPES THIS FAR OUT BUT
DID TRY TO PUT A "BEST GUESS" IN THE GRIDS FOR NOW...BASED ON
CONSENSUS OF FORECAST LOW TRACK AND THERMAL PROFILES. PREFERENCE
LIES WITH A GFS/ECMWF COMBO. NAM SURFACE TEMPS APPEAR TOO COLD AND
QPF AMOUNTS TOO LIGHT. GEM THERMAL PROFILES ARE DECENT BUT KEEPS
PRECIP LOCKED UP TOO FAR NORTH. SUPPOSE THIS IS POSSIBLE IF FORECAST
TRACK IS IN LARGE ERROR BUT SOLUTIONS HAVE BEEN FAIRLY STABLE THUS
FAR AND SUSPECT MOST AREAS WILL SEE AT LEAST SOME LIGHT PRECIP WITH
A MODEST PV ANOMALY PASSING DIRECTLY OVERHEAD. THIS IS ESPECIALLY
TRUE GIVEN SUPERB MOISTURE AVAILABILITY WITH 700MB MIXING RATIOS
OVER 4 G/KG AND PW VALUES AROUND 0.75 INCHES. AS FAR AS PRECIP
TYPES...EXPECT COLD SURFACE TEMPS TO SUPPORT FREEZING RAIN AT THE
ONSET...TRANSITIONING TO ALL RAIN FROM SOUTH TO NORTH EARLY THURSDAY
MORNING. LATENT HEAT RELEASE DUE TO FREEZING AND CONTINUAL WAA WITH
S/SW SURFACE WINDS SHOULD LEAD TO A NONDIURNAL TEMPERATURE TREND AND
A FAIRLY QUICK CHANGEOVER TO RAIN WITH MINIMAL ICE ACCUMULATION.
STILL COULD BE SOME SLICK ROADS DURING THE EARLY MORNING COMMUTE
THOUGH...ESPECIALLY NORTH OF US-30. ATYPICAL DIURNAL TEMP TREND
CONTINUES ON THURSDAY WITH HIGHS PROBABLY OCCURRING IN THE LATE
MORNING AND THEN FALLING THROUGH THE AFTERNOON AS COLDER AIR WRAPS
BACK AROUND EXITING LOW. THIS WILL LEAD TO A CHANGE BACK TO SNOW
FROM NORTH TO SOUTH WITH SOME TRANSITORY SLEET MIXING IN AS WELL.
EXPECT SNOW AMOUNTS AROUND AN INCH AT MOST WITH THE HIGHEST AMOUNTS
IN OUR FAR NORTHEAST. ANY ACCUMULATION OF FREEZING RAIN AT THE ONSET
WILL BE LESS THAN A TENTH OF AN INCH. SOME LIGHT LAKE EFFECT/
ENHANCED SNOW POSSIBLE THURSDAY NIGHT BUT BY AND LARGE EVENT WILL BE
WINDING DOWN BY THEN.
NEXT CHANCE OF SNOW LOOKS TO BE ON SUNDAY AS ELONGATED/POSITIVELY
TILTED TROUGH SWINGS THROUGH THE CENTRAL CONUS. MODELS HAVE SHOWN A
HIGH DEGREE OF VARIABILITY DURING THIS TIMEFRAME SO FORECAST
CONFIDENCE IS LOW. DID FOCUS THE POP FORECAST A BIT BUT WILL HOLD
OFF FOR A FEW MORE RUNS BEFORE LATCHING ONTO ANY SPECIFICS. STILL
LOOKS LIKE AT LEAST A GLANCING BLOW OF MUCH COLDER AIR BEHIND THIS
SYSTEM ON MONDAY. NUDGED THE FORECAST TOWARD COLDER RAW GUIDANCE
WITH HIGHS IN THE TEENS AND LOWS FLIRTING WITH 0F.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1237 AM EST TUE JAN 27 2015
ANOTHER TRICKY AVIATION FORECAST WITH RESPECT TO CLOUD HEIGHTS
THIS PERIOD. TERMINALS REMAIN VFR AT ISSUANCE BUT MVFR AND IFR
CONDITIONS EXISTS JUST WEST OF KSBN. KMCY AND KOXI HAVE DROPPED
TO 25HFT WHILE KVPZ DOWN TO 1KFT WITH SOME LIGHT SNOW AT TIMES.
LOW LEVEL FLOW BEING SHOWN BY HIRES GUIDANCE TO SLOWLY TURN
NORTHEAST AND INCREASE SLIGHTLY TO AROUND 5-8 KNOTS NEXT FEW
HOURS. THIS SHOULD SLOW OR END THE EASTWARD EXPANSION OF MVFR CIGS
AND EVENTUALLY PUSH THEM SOUTHWEST. HOWEVER...WITH PROXIMITY TO
KSBN HAD TO ADD A FEW HOURS OF TEMPO MVFR TO ACCOUNT FOR
POSSIBILITY OF THESE CLOUDS. NORTHEAST FLOW SHOULD EVENTUALLY
ALLOW SLIGHTLY DRIER LOW LEVEL AIR TO WORK WEST WITH VFR
CONDITIONS INTO TUESDAY. NEXT CONCERN IS LOW LEVEL CLOUDS OVER
CENTRAL OHIO MAKING A RUN WEST AS THIS LOW LEVEL FLOW CHANGES. RUC
MODEL BRINGS HIGHER RH INTO KFWA TUESDAY MORNING. HAVE INTRODUCED
A SCATTERED DECK AT 25HFT FOR NOW BUT THIS WILL BE MONITORED FOR
POSSIBLE ADDITION OF MVFR CIGS TO LATER FORECASTS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
300 AM EST TUE JAN 27 2015
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 152 PM EST MON JAN 26 2015
A QUICK MOVING WEATHER DISTURBANCE WILL PUSH ACROSS ILLINOIS AND
INDIANA THIS EVENING...BRINGING CHANCES FOR SOME LIGHT SNOW THIS
EVENING TO WESTERN PARTS OF CENTRAL INDIANA.
COLD HIGH PRESSURE IS EXPECTED TO ARRIVE ON TUESDAY AND CONTINUE
TO REMAIN IN THE AREA THROUGH WEDNESDAY NIGHT. THIS WILL RESULT IN
DRY WEATHER WITH BELOW NORMAL TEMPERATURES. ANOTHER QUICK MOVING
AREA OF LOW PRESSURE IS EXPECTED TO ARRIVE AND PASS ACROSS CENTRAL
INDIANA ON EARLY THURSDAY MORNING...ONCE AGAIN RESULTING IN CHANCES
FOR PRECIPITATION.
ANOTHER WEAK LOW PRESSURE SYSTEM IS EXPECTED TO PUSH ACROSS THE
REGION THIS WEEKEND...ONCE AGAIN RESULTING IN CHANCES FOR
PRECIPITATION.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1039 PM EST MON JAN 26 2015
UPDATE...
INSERTED MENTION OF PATCHY FREEZING DRIZZLE ACROSS THE WESTERN
PORTIONS OF CENTRAL INDIANA. FREEZING DRIZZLE HAS BEEN REPORTED
UPSTREAM. CONTINUED TO LEAVE FAR NORTHEAST COUNTIES DRY EXCEPT FOR
A FEW FLURRIES. UPDATED GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
MAIN FORECAST CHALLENGE WILL BE PRECIP THIS EVENING. GFS SUGGESTS
THE UPPER WAVE RESPONSIBLE FOR THE ONGOING SNOW OVER ILLINOIS WILL
CONTINUE TO DIVE SSE AMID THE QUICK FLOW ALOFT. HRRR SHOW PRECIP
MAINLY CONTAINED TO THE WESTERN PARTS OF THE FORECAST AREA. TIME
HEIGHTS THIS EVENING SHOW BEST SATURATION IN THE WESTERN AND
SOUTHERN PARTS OF THE FORECAST AREA...WITH LESS MOISTURE AVAILABLE
ACROSS THE NORTHEAST. ISENTROPIC SURFACE SHOWS LITTLE TO NO HELP
AS THIS SYSTEM PASSES. FORECAST SOUNDINGS ACROSS WESTERN INDIANA
CONTINUE TO SHOW GOOD LOW AND MID LEVEL SATURATION THROUGH THE
NIGHT.
THUS WILL RAISE POPS...PARTICULARLY ACROSS THE WESTERN PARTS OF
THE FORECAST AREA...TRENDING TOWARD A FLURRY OR DRY FORECAST ACROSS
THE FAR NORTHEAST. AS FOR TEMPS...CLOUDS ARE EXPECTED THROUGH MUCH
OF THE NIGHT AS THE UPPER WAVE PASSES AND TEMPERATURE ADVECTION IS
NEUTRAL. THUS WILL STICK CLOSE TO A BLEND ON TEMPS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 152 PM EST MON JAN 26 2015
MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE TEMPS INITIALLY
FOLLOWED BY PRECIPITATION CHANCES ON THURSDAY.
DRY AND COLD WEATHER IS EXPECTED THROUGH WEDNESDAY DUE TO THE
FOLLOWING REASONS:
SURFACE HIGH PRESSURE BUILDING OUT OF CANADA WILL BUILD ACROSS AND
PASS OVER CENTRAL INDIANA THROUGH WEDNESDAY NIGHT. TIME HEIGHT
SECTIONS THROUGH WEDNESDAY NIGHT CONTINUE TO SHOW A DRY COLUMN
AMID SUBSIDENCE. FORECAST SOUNDINGS AGREE...ONLY SHOWING SOME
SATURATION NEAR 12Z THURSDAY. MEANWHILE ALOFT...A DEEP TROUGH OVER
EASTERN 1/2 OF THE UNITED STATES WILL CONTINUE TO PROVIDE A VERY
COLD AND NW FLOW TO CENTRAL INDIANA. THIS WILL HELP IN RESULTING
IN BELOW NORMAL TEMPERATURES. THUS WITH ONLY A FEW QUICK PASSING
HIGH CLOUDS EXPECTED...WILL TREND TOWARD PARTLY CLOUDY ON TUESDAY
THROUGH WEDNESDAY EVENING...ALONG WITH A BLEND ON TEMPS.
ON LATE WEDNESDAY NIGHT THE GFS INDICATES A WELL ORGANIZED SHORT
WAVE ALOFT PUSHING INTO INDIANA FROM THE WEST. ONCE
AGAIN...FORECAST SOUNDINGS HINT AT LOWER LEVEL SATURATION AHEAD OF
THIS SYSTEM. SOUNDINGS ALSO SHOW WARM AIR ADVECTION IN THE LOWEST
LEVELS THAT WILL ALLOW ANY PRECIP ON THURSDAY MORNING TO FALL AS
RAIN. 300K GFS ISENTROPIC SURFACE SHOWS GOOD UPGLIDE ALONG WITH A
SURGE OF SPECIFIC HUMIDITIES OF 2 G/KG. THUS ROUND OF LIGHT PRECIP
IS EXPECTED. BY THURSDAY AFTERNOON THE UPPER SHORT WAVE LOOKS TO
BE WELL EAST OF INDIANA AND COLD AIR ADVECTION WILL ONCE AGAIN BE
IN PLAY. FORECAST SOUNDINGS SHOW THE SATURATED LOWER PARTS OF THE
COLUMN FALLING BELOW FREEZING...THUS A CHANGE OVER TO SNOW DURING
THE AFTERNOON FOR ANY LINGERING PRECIP LOOKS REASONABLE. HOWEVER
WITH A LACK OF DEEP MOISTURE AND THE BEST FORCING OFF TO THE
EAST...ANY SNOW AMOUNTS WILL BE QUITE LIGHT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
ISSUED AT 300 AM EST TUE JAN 27 2015
NORTHWEST FLOW ALOFT AND STRONG CANADIAN HIGH PRESSURE WILL ENSURE
A COLD START TO THE EXTENDED PERIOD ON FRIDAY IN THE WAKE OF THE
COLD FRONTAL PASSAGE ON THURSDAY. THE HIGH WILL DRIFT EAST THROUGH
SATURDAY MAINTAINING DRY CHILLY CONDITIONS ACROSS CENTRAL INDIANA.
HIGHS WILL GENERALLY RANGE FROM THE UPPER 20S TO MID 30S BOTH DAYS.
THE MAIN FOCUS FOR THE EXTENDED PERIOD COMES DURING THE SECOND
HALF OF THE WEEKEND AS A STRENGTHENING SURFACE WAVE TRACKS FROM
THE WESTERN GULF SUNDAY MORNING INTO NEW ENGLAND BY MONDAY. MODEL
GUIDANCE HAS WAVERED WITH THE HANDLING OF THIS SYSTEM OVER THE
LAST FEW DAYS RANGING FROM A SUPPRESSED SYSTEM TRACKING THROUGH
THE SOUTHERN STATES TO A MORE PHASED SOLUTION BRINGING A GREATER
IMPACT NORTH INTO THE OHIO VALLEY. 00Z GUIDANCE IN GENERAL HAS
TRENDED BACK TOWARDS THE MORE PHASED UPPER WAVE WITH A SURFACE
WAVE TRACKING THROUGH THE TENNESSEE VALLEY SUNDAY INTO SUNDAY
NIGHT AND A BROAD AREA OF OVERRUNNING PRECIPITATION SPREADING
ACROSS THE ENTIRE REGION.
WITH COLD AIR LINGERING ACROSS CENTRAL INDIANA AND THE TRACK TO
THE SOUTH OF THE FORECAST AREA...PRECIP WOULD LIKELY FALL AS SNOW
AS IT STANDS NOW WITH POSSIBLY A BRIEF PERIOD OF MIXED PRECIP ON
SUNDAY DEPENDING ON THE AMOUNT OF WARMTH IN THE BOUNDARY LAYER
THAT CAN TAKE PLACE. STILL SEVERAL DAYS OUT AND LIKELY TO SEE
ADDITIONAL CHANGES AS WE NEAR THE WEEKEND. ONE CAVEAT TO KEEP IN
MIND...MODEL GUIDANCE IN GENERAL HAS UNDERDONE LOW LEVEL WARM
INTRUSIONS AND CAUSED PRECIP TYPE CHALLENGES ACROSS THE FORECAST
AREA WITH SURFACE WAVES ALL WINTER LONG. NOT SAYING THIS HAPPENS
HERE IF THE FORECAST TRACK THROUGH THE TENNESSEE AND LOWER OHIO
VALLEYS HOLDS. IT IS JUST SOMETHING TO KEEP IN MIND AS MODELS HONE
IN ON A CONSENSUS SOLUTION IN THE COMING DAYS. SHOULD THINGS COME
TOGETHER FOR A PREDOMINANT SNOW EVENT...POTENTIAL IS THERE FOR A
FEW INCHES OF ACCUMULATION LATE SATURDAY NIGHT THROUGH SUNDAY
NIGHT.
ONCE THE SURFACE WAVE PASSES AND DEEPENS OFF THE NEW ENGLAND COAST
MONDAY...A FRESH BATCH OF ARCTIC AIR WILL SPILL INTO THE REGION
FOR EARLY NEXT WEEK. HIGHS MAY STRUGGLE TO GET OUT OF THE TEENS
BOTH MONDAY/TUESDAY ACROSS NORTHERN COUNTIES.
&&
.AVIATION /DISCUSSION FOR THE 270600Z TAF ISSUANCE/...
ISSUED AT 1140 PM EST MON JAN 26 2015
IFR OR WORSE CONDITIONS IN LIGHT SNOW EXPECTED MUCH OF THE NIGHT AT
BMG AND HUF. MVFR OR WORSE POSSIBLE AT LAF THROUGH 07Z OR 08Z IN
LIGHT SNOW OR LIGHT DRIZZLE. BUFKIT DOES NOT FAVOR FREEZING DRIZZLE
AT THE OTHER SITES...HOWEVER RECENT REPORTS OF LIGHT FREEZING
DRIZZLE AT LAF AND NORTH AND WEST DEMAND AT LEAST A MENTION.
PRECIPITATION SHOULD BE ENDING FROM NORTHWEST TO SOUTHEAST...AFTER
09Z AT IND AND HUF AND 10Z AT BMG. FLYING CONDITIONS SHOULD IMPROVE
TO MVFR OR VFR AFTER 15Z WITH ONLY CIRRUS AFTER 00Z WEDNESDAY.
WINDS WILL BE LIGHT AND VARIABLE TO CALM OVERNIGHT AND BECOME
NORTHEAST AND NORTH 8 KNOTS OR LESS AFTER 15Z BEFORE BECOMING LIGHT
AND VARIABLE ONCE AGAIN AFTER 00Z WEDNESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...TDUD
SHORT TERM...PUMA
LONG TERM....RYAN
AVIATION...KOCH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1141 PM EST MON JAN 26 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 152 PM EST MON JAN 26 2015
A QUICK MOVING WEATHER DISTURBANCE WILL PUSH ACROSS ILLINOIS AND
INDIANA THIS EVENING...BRINGING CHANCES FOR SOME LIGHT SNOW THIS
EVENING TO WESTERN PARTS OF CENTRAL INDIANA.
COLD HIGH PRESSURE IS EXPECTED TO ARRIVE ON TUESDAY AND CONTINUE
TO REMAIN IN THE AREA THROUGH WEDNESDAY NIGHT. THIS WILL RESULT IN
DRY WEATHER WITH BELOW NORMAL TEMPERATURES. ANOTHER QUICK MOVING
AREA OF LOW PRESSURE IS EXPECTED TO ARRIVE AND PASS ACROSS CENTRAL
INDIANA ON EARLY THURSDAY MORNING...ONCE AGAIN RESULTING IN CHANCES
FOR PRECIPITATION.
ANOTHER WEAK LOW PRESSURE SYSTEM IS EXPECTED TO PUSH ACROSS THE
REGION THIS WEEKEND...ONCE AGAIN RESULTING IN CHANCES FOR
PRECIPITATION.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1039 PM EST MON JAN 26 2015
UPDATE...
INSERTED MENTION OF PATCHY FREEZING DRIZZLE ACROSS THE WESTERN
PORTIONS OF CENTRAL INDIANA. FREEZING DRIZZLE HAS BEEN REPORTED
UPSTREAM. CONTINUED TO LEAVE FAR NORTHEAST COUNTIES DRY EXCEPT FOR
A FEW FLURRIES. UPDATED GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
MAIN FORECAST CHALLENGE WILL BE PRECIP THIS EVENING. GFS SUGGESTS
THE UPPER WAVE RESPONSIBLE FOR THE ONGOING SNOW OVER ILLINOIS WILL
CONTINUE TO DIVE SSE AMID THE QUICK FLOW ALOFT. HRRR SHOW PRECIP
MAINLY CONTAINED TO THE WESTERN PARTS OF THE FORECAST AREA. TIME
HEIGHTS THIS EVENING SHOW BEST SATURATION IN THE WESTERN AND
SOUTHERN PARTS OF THE FORECAST AREA...WITH LESS MOISTURE AVAILABLE
ACROSS THE NORTHEAST. ISENTROPIC SURFACE SHOWS LITTLE TO NO HELP
AS THIS SYSTEM PASSES. FORECAST SOUNDINGS ACROSS WESTERN INDIANA
CONTINUE TO SHOW GOOD LOW AND MID LEVEL SATURATION THROUGH THE
NIGHT.
THUS WILL RAISE POPS...PARTICULARLY ACROSS THE WESTERN PARTS OF
THE FORECAST AREA...TRENDING TOWARD A FLURRY OR DRY FORECAST ACROSS
THE FAR NORTHEAST. AS FOR TEMPS...CLOUDS ARE EXPECTED THROUGH MUCH
OF THE NIGHT AS THE UPPER WAVE PASSES AND TEMPERATURE ADVECTION IS
NEUTRAL. THUS WILL STICK CLOSE TO A BLEND ON TEMPS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 152 PM EST MON JAN 26 2015
MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE TEMPS INITIALLY
FOLLOWED BY PRECIPITATION CHANCES ON THURSDAY.
DRY AND COLD WEATHER IS EXPECTED THROUGH WEDNESDAY DUE TO THE
FOLLOWING REASONS:
SURFACE HIGH PRESSURE BUILDING OUT OF CANADA WILL BUILD ACROSS AND
PASS OVER CENTRAL INDIANA THROUGH WEDNESDAY NIGHT. TIME HEIGHT
SECTIONS THROUGH WEDNESDAY NIGHT CONTINUE TO SHOW A DRY COLUMN
AMID SUBSIDENCE. FORECAST SOUNDINGS AGREE...ONLY SHOWING SOME
SATURATION NEAR 12Z THURSDAY. MEANWHILE ALOFT...A DEEP TROUGH OVER
EASTERN 1/2 OF THE UNITED STATES WILL CONTINUE TO PROVIDE A VERY
COLD AND NW FLOW TO CENTRAL INDIANA. THIS WILL HELP IN RESULTING
IN BELOW NORMAL TEMPERATURES. THUS WITH ONLY A FEW QUICK PASSING
HIGH CLOUDS EXPECTED...WILL TREND TOWARD PARTLY CLOUDY ON TUESDAY
THROUGH WEDNESDAY EVENING...ALONG WITH A BLEND ON TEMPS.
ON LATE WEDNESDAY NIGHT THE GFS INDICATES A WELL ORGANIZED SHORT
WAVE ALOFT PUSHING INTO INDIANA FROM THE WEST. ONCE
AGAIN...FORECAST SOUNDINGS HINT AT LOWER LEVEL SATURATION AHEAD OF
THIS SYSTEM. SOUNDINGS ALSO SHOW WARM AIR ADVECTION IN THE LOWEST
LEVELS THAT WILL ALLOW ANY PRECIP ON THURSDAY MORNING TO FALL AS
RAIN. 300K GFS ISENTROPIC SURFACE SHOWS GOOD UPGLIDE ALONG WITH A
SURGE OF SPECIFIC HUMIDITIES OF 2 G/KG. THUS ROUND OF LIGHT PRECIP
IS EXPECTED. BY THURSDAY AFTERNOON THE UPPER SHORT WAVE LOOKS TO
BE WELL EAST OF INDIANA AND COLD AIR ADVECTION WILL ONCE AGAIN BE
IN PLAY. FORECAST SOUNDINGS SHOW THE SATURATED LOWER PARTS OF THE
COLUMN FALLING BELOW FREEZING...THUS A CHANGE OVER TO SNOW DURING
THE AFTERNOON FOR ANY LINGERING PRECIP LOOKS REASONABLE. HOWEVER
WITH A LACK OF DEEP MOISTURE AND THE BEST FORCING OFF TO THE
EAST...ANY SNOW AMOUNTS WILL BE QUITE LIGHT.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 250 PM EST MON JAN 26 2015
ONE SYSTEM WILL BE EXITING OUR REGION THURSDAY EVENING...THUS WILL
CONTINUE A SLIGHT CHANCE OF SNOW EAST AND CENTRAL THURSDAY EVENING.
HIGH PRESSURE BEHIND THIS SYSTEM WILL MOVE ACROSS OUR REGION FRIDAY
NIGHT AND IT NOW LOOKS LIKE DRY WEATHER WILL BE THE RULE THROUGH
SATURDAY.
ANOTHER SYSTEM WILL BRING US A CHANCE OF SNOW SATURDAY NIGHT INTO
SUNDAY AS THE MODELS HAVE TRENDED SLOWER WITH THIS SYSTEM.
FINALLY COLDER AND DRY WEATHER WILL BE THE RULE REST OF THE LONG
TERM AS A LONG WAVE TROUGH AMPLIFIES OVER THE EASTERN U.S. THE
MODELS HAVE TRENDED A LITTLE COLDER DURING THIS PERIOD. BUT ALL AND
ALL WENT CLOSE TO A MOS BLEND ON TEMPERATURES.
&&
.AVIATION /DISCUSSION FOR THE 270600Z TAF ISSUANCE/...
ISSUED AT 1140 PM EST MON JAN 26 2015
IFR OR WORSE CONDITIONS IN LIGHT SNOW EXPECTED MUCH OF THE NIGHT AT
BMG AND HUF. MVFR OR WORSE POSSIBLE AT LAF THROUGH 07Z OR 08Z IN
LIGHT SNOW OR LIGHT DRIZZLE. BUFKIT DOES NOT FAVOR FREEZING DRIZZLE
AT THE OTHER SITES...HOWEVER RECENT REPORTS OF LIGHT FREEZING
DRIZZLE AT LAF AND NORTH AND WEST DEMAND AT LEAST A MENTION.
PRECIPITATION SHOULD BE ENDING FROM NORTHWEST TO SOUTHEAST...AFTER
09Z AT IND AND HUF AND 10Z AT BMG. FLYING CONDITIONS SHOULD IMPROVE
TO MVFR OR VFR AFTER 15Z WITH ONLY CIRRUS AFTER 00Z WEDNESDAY.
WINDS WILL BE LIGHT AND VARIABLE TO CALM OVERNIGHT AND BECOME
NORTHEAST AND NORTH 8 KNOTS OR LESS AFTER 15Z BEFORE BECOMING LIGHT
AND VARIABLE ONCE AGAIN AFTER 00Z WEDNESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...TDUD
SHORT TERM...PUMA
LONG TERM....JH
AVIATION...KOCH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
358 AM CST TUE JAN 27 2015
.SHORT TERM /TODAY/...
ISSUED AT 355 AM CST TUE JAN 27 2015
MAIN CONCERNS TODAY WILL BE TEMPS AND CLOUD COVER THROUGH THE
MORNING HOURS...AND PERHAPS A PORTION OF THE AFTERNOON EAST. TO
VARYING DEGREES...MODELS ALL HINT AT SOME CLOUDS MOVING SOUTHEAST
ALONG THE EASTERN EDGE OF THE H700 RIDGE CAUGHT IN THE NORTHWEST
FLOW EARLY TODAY. HOWEVER...NONE OF THE MODELS IS DOING VERY WELL.
THE HRRR AND NMM WRF MAY HAVE A SLIGHTLY BETTER HANDLE ON THE
SITUATION. EXAMINING THE UPPER LEVEL H700 RIDGE THROUGH THE DAY
TODAY SHOWS THAT IT IS LIKELY TO CONTINUE BUILDING EAST THROUGH THE
AFTERNOON HOURS...ENDING ANY CYCLONIC PORTION OF CIRCULATION WHICH
IS ASSOCIATED WITH THE LEFTOVER SYSTEM FROM YESTERDAY. AT 00Z TUE
THE H850 ANALYSIS SHOWED A PRONOUNCED WAVE TRACKING THROUGH EASTERN
IOWA BACK NORTH TOWARD MINNEAPOLIS...BUT NORTHWEST OF THERE THE FLOW
BECOMES MORE ANTICYCLONIC OVER THE EASTERN DAKOTAS. ANOTHER UPSTREAM
TROUGH IS ALREADY DEVELOPING WITH AN ATTENDANT WARM FRONT OVER THE
WESTERN DAKOTAS. SOME CLOUDS OVER SASKATCHEWAN AND MANITOBA MAY
TRACK SOUTHEAST TOWARD THE REGION THIS AFTERNOON BUT LIKELY ONLY
AFFECT THE FAR EASTERN COUNTIES WITH MID TO HIGH LEVEL CLOUDS. BASED
ON CLOUDS AND LATER TRAJECTORIES...COOLER HIGHS WILL BE HAD OVER THE
NORTHEAST HALF OF THE FORECAST AREA WHILE THE SOUTHWEST HALF WILL
REMAIN MILD FOR JANUARY...BUT NOT AS WARM AS YESTERDAY. WITH A
RATHER WEAK RIDGE AXIS PASSING OVER THE AREA TODAY WINDS WILL REMAIN
LIGHT. HIGHS WILL RANGE FROM THE UPPER 30S NORTHEAST TO THE UPPER
40S SOUTHWEST.
.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 355 AM CST TUE JAN 27 2015
AM EXPECTING MAX TEMPS FOR WED TO BE VERY SIMILAR TO MONDAY`S HIGHS.
A WARM FRONT WILL CUT ACROSS THE MIDDLE OF THE CWA...LEADING TO A
NOTABLE TEMP GRADIENT...FROM NW TO SE. LOW 40S EXPECTED IN NE CWA
AND UPPER 50S IN SW CWA. NAM MORE AGGRESSIVE WITH LOW LEVEL CLOUD
COVER AND THUS IS A COOL OUTLIER. NAM ALSO STILL THINKS THERE IS
SNOW ACROSS THE CWA SO AM DISCARDING NAM SOLUTION.
A VERY FAST MOVING SHORTWAVE TO IMPACT CWA THURSDAY MORNING. THROUGH
WATER VAPOR IMAGERY...THIS SHORTWAVE CAN BE EASILY PICKED UP COMING
ONTO THE CALIFORNIA COAST AT 06Z TUE. MODELS INITIALIZING WELL WITH
PLACEMENT OF THIS LOW AS IT COMES ONSHORE.
ADDITIONALLY...MODELS CONVERGING ON SOLUTION OF PUTTING THE WAVE
DIRECTLY OVER CENTRAL IOWA AT 06Z THU. THERE IS A SIZABLE DRY AIR
POCKET FROM AROUND 850MB TO 500MB WHICH WILL PREVENT CLOUD
THICKNESS FROM EXCEEDING 5 KFT AND...SUBSEQUENTLY...KEEP THIS
SYSTEM FROM PRODUCING ANYTHING BEYOND LIGHT PRECIP. HAVE BUMPED
UP TEMPS FROM PVS SHIFT. KMCW TO KEST GFS SOUNDINGS SUPPORT MAINLY
DZ/-RA...WITH A VERY NARROW WINDOW OF -IP TO -SN POSSIBLE FROM
AROUND 09Z TO 12Z. PROFILE DURING THIS TIME IS BELOW ZERO UNTIL
NEAR SFC...WHICH IS NOT ENOUGH WARM LAYER DEPTH TO FULLY MELT ALL
SNOW FLAKES. BY 12Z THU...THIS LOW WILL BE OVER NORTHERN ILLINOIS
AND STRONG CAA PLUS SUBSIDENCE WILL BE ADVECTED INTO OUR CWA.
THOUGH SUNSHINE EXPECTED...DAYTIME TEMPS TO ONLY WARM AROUND 3 TO
5 DEGREES FROM OVERNIGHT MINS DUE TO CAA.
THURSDAY`S WINDS ALSO WORTH MENTIONING. MODELS SHOWING 25 KT TO 30
KT WINDS RIGHT OFF THE DECK...APPROACHING 35 KT TO 40 KT TO THE TOP
OF THE MIXED LAYER. SFC PRESSURE GRADIENT OF 3MB/100KM TO SUPPORT
STRONG WINDS AT THE SFC. IN ALL...MAY APPROACH WIND ADVISORY
CRITERIA STARTING EARLY THU AM AND HEADLINE MAY BE WARRANTED IF THIS
SOLUTION HOLDS. A STRONG SFC HIGH WILL MOVE THROUGH THE MIDWEST
FRIDAY...KEEPING FRIDAY QUIET AND HELPING TO DECOUPLE WINDS HEADING
INTO SATURDAY.
FOR THIS WEEKEND...THE 00Z RUNS ARE HOLDING AS THEY ARE SHOWING AN
ALBERTA CLIPPER TYPE SYSTEM LOOKS TO PASS THROUGH THE GREAT LAKES
REGION. THERE WILL BE AN ATTENDANT COLD FRONT TO THIS LOW WHICH IS
BEING PROGGED TO PROPAGATE THROUGH THE CWA SUNDAY MORNING. THE
TIMING HAS CHANGED SOME FROM THE 12Z MON MODEL RUNS TO THE 00Z TUE
RUNS...WITH THE EURO AND GFS DROPPING BACK FROPA UNTIL AROUND 06Z
TO 12Z SUN. MODELS SATURATE THE SKIES FROM TOP DOWN IN ADVANCE OF
THIS SYSTEM...STARTING SATURDAY MORNING. PUSHING TIMING BACK SEEMS
REASONABLE...AS LOW LEVELS NOT SATURATED UNTIL AFTER 00Z SUN. THUS
HAVE PUSHED BACK POPS SLIGHTLY. SOUNDING PROFILE COMPLETELY
SATURATED AND WELL BELOW FREEZING SUNDAY MORNING. HAVE BEGUN TO
NUDGE SUNDAY MORNING POPS UPWARD...WITH FURTHER INCREASES
CERTAINLY POSSIBLE IF THE MODEL SOLNS CONTINUE TO HOLD.
THE PAST FEW MODEL RUNS HAVE CERTAINLY BEEN TRENDING DOWNWARD WITH
TEMPERATURES BEHIND THIS FRONT. ENSEMBLES HAVE 850 MB TEMPS DOWN TO
THE -12C TO -15C RANGE ACROSS THE CWA. SINGLE DIGIT TEMPERATURES
APPEAR VERY POSSIBLE MONDAY AND TUESDAY MORNING.
&&
.AVIATION...27/06Z
ISSUED AT 1131 PM CST MON JAN 26 2015
PRIMARY CONCERN REMAINS PROGRESSION OF MVFR/VFR STRATUS THAT
EXTENDS ALONG AND NE OF KEST-KDSM-KTVK LINE AT 06Z WITH PATCH OF
CLEAR SKIES OVER ERN IA FROM KALO-KOTM. MORE WIDESPREAD LOWER CIGS
THEN EXTEND ALL THE WAY BACK INTO MN...WI AND IL IN BROAD
CYCLONIC FLOW. NONE OF THE MODELS SEEM TO HAVE A GREAT HANDLE
ON CURRENT CONDITIONS ACROSS IA...BUT ALL MODELS SEEM TO SLIDE
THE STRATUS SLOWLY SOUTH AND WEST INTO TUE MORNING. THERE IS HIGH
CONFIDENCE THAT AT LEAST PATCHY MVFR CIGS WILL OOZE SW THROUGH IA...BUT
DURATION CONFIDENCE IS LOW. HAVE LEFT ENDING TIME AT 16Z UNTIL
EXIT TRENDS BECOME MORE CLEAR. RAP AND NAM SUGGEST IN SIMILAR
LOCATIONS WILL INTO TUE...WHILE HIGH RES NMM/ARW MODELS ARE MORE
OPTIMISTIC.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...REV
LONG TERM...KOTENBERG
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1131 PM CST MON JAN 26 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 341 PM CST MON JAN 26 2015
HIGH PRESSURE RIDGE WILL SHIFT SLOWLY EAST OVERNIGHT AND BE OVER
CENTRAL MINNESOTA AND INTO NW IOWA BY MORNING. OVERNIGHT WINDS WILL
BE OUT OF THE NORTHWEST TO NORTH MUCH OF THE NIGHT. THIS FLOW WILL
EXTEND UP TO NEAR 3-4 KFT AND WILL BE THE STEERING FLOW FOR A BAND
OF STRATUS CLOUDS TO THE NORTH OVER MINNESOTA. THE STRATUS WILL DROP
SOUTH INTO NORTHERN AND CENTRAL IOWA OVERNIGHT AND COMBINED WITH
WINDS 5 TO 8 MPH WILL KEEP TEMPERATURES IN UP OVERNIGHT. CURRENT
DEWPOINTS ARE HIGH AND WELL INTO THE 30S. AS TEMPERATURES
COOL...SOME QUESTION TO THE POTENTIAL FOR FOG FORMATION. STILL WITH
CLOUDS MOVING IN FROM THE NORTH AND PERSISTENT NORTHERLY WINDS...FOG
FORMATION SHOULD BE LIMITED. BEST POTENTIAL WILL BE OVER THE FAR
WEST AS WINDS DIMINISH AS THE RIDGE NEARS FROM THE WEST. DEWPOINTS
ARE EXPECTED TO LOWER OVERNIGHT AS SFC WINDS BECOME MORE NORTHERLY
WITH DEW POINT DEPRESSIONS INCREASING WHICH WILL LIMIT FOG POTENTIAL
AS WELL. LIKELY THE BIGGER HAZARD OVERNIGHT WILL BE FROST FORMATION
ON ROADS WHERE DEWPOINTS REMAIN HIGHER THAN GROUND TEMPERATURES.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 341 PM CST MON JAN 26 2015
MODEL RESOLUTION IN THE FURTHER OUT PERIODS (SATURDAY THROUGH
MONDAY) OF THE LONG TERM FORECAST ARE COMING INTO A LITTLE BETTER
AGREEMENT TODAY...ALTHOUGH TIMING ISSUES REMAIN. THE GFS IS
STARTING TO LOOK MORE LIKE THE EURO AND CANADIAN MODELS NOW WITH
DEVELOP A TROUGH OVER THE REGION INSTEAD OF A HUGE RIDGE. THAT
MEANS TEMPS WILL BE TRENDING COLDER OVER THE WEEKEND. BY SUNDAY
MODELS ARE SUGGESTING HIGHS ABOUT 8 TO 10 DEGREES BELOW SEASONAL
NORMALS. THERE IS A CHANCE FOR SNOW SATURDAY/SATURDAY NIGHT WITH
THE PASSAGE OF A COLD FRONT BUT AGAIN TIMING ISSUES REMAIN WITH THE
CANADIAN MUCH FASTER AND THE GFS MUCH WETTER. ALONG WITH THE COLD
AND SNOW POTENTIAL...SATURDAY NIGHT AND SUNDAY LOOK BREEZY AS WELL.
WINTER RETURNS NEXT WEEKEND.
GOING BACK TO TOMORROW (TUESDAY) SOUNDINGS SHOW A WARM NOSE OFF THE
SURFACE WHICH IS MORE PRONOUNCED ACROSS THE SOUTH BUT WINDS WILL BE
NORTHERLY AND WIND SPEEDS IN THE LOWEST GATES ARE QUITE LIGHT. AS A
SURFACE LOW MOVES FROM THE PLAINS INTO THE UPPER MIDWEST...SURFACE
WINDS WILL SHIFT AROUND TO THE SOUTHEAST BUT STILL REMAIN LIGHT SO
IT DOES NOT APPEAR THAT THERE WILL BE MUCH MIXING. COUNTERING THAT
WILL BE A LOT OF SUN SO WHILE WE WILL NOT BE AS WARM AS
TODAY...TEMPS SHOULD STILL REACH THE MID 30S NORTHEAST TO LOWER 50S
SOUTHWEST.
DEEPER MIXING AND A LITTLE STRONGER FLOW WILL OCCUR TUESDAY NIGHT
AND WEDNESDAY AND THIS WILL BE OUR WARMEST PERIOD. EXPECTED CLOUD
COVER AHEAD OF AN APPROACHING STILL MAKES ME A LITTLE CAUTIOUS TO
BOOST TEMPS TOO MUCH ON WEDNESDAY...ESPECIALLY SINCE THE SURFACE LOW
SHIFTS INTO THE AREA DURING THE AFTERNOON AND WINDS DIMINISH/SHIFT
BY LATE IN THE DAY BUT I AM COMFORTABLE WITH CURRENT FORECASTS SINCE
THE WARM ADVECTION WILL BE STRONG. EXCEPT FOR THE CANADIAN...ALL
MODELS ARE SIMILAR IN THE TIMING OF THE SHORTWAVE BUT IF THE
SHORTWAVE IS SLOWER OR CLOUD COVER IS NOT EXTENSIVE THEN WE WILL BE
TOO COOL FOR WEDNESDAY. STILL GOING DRY WEDNESDAY WITH JUST SOME
INCREASING CLOUDS THROUGH THE DAY WHICH COULD HAMPER HIGHS.
WHILE MOISTURE WITH THE WEDNESDAY SYSTEM IS WOEFULLY LACKING...IT
SHOULD IMPROVE WEDNESDAY NIGHT...AT LEAST IN THE LOW LEVELS. PRECIP
WILL BE POSSIBLE ALONG AND WITH THE PASSAGE OF A COLD FRONT AND A
SECOND SHORT WAVE WEDNESDAY NIGHT BUT THERE IS NO ICE INTRODUCTION
AND FRANKLY ABOVE 850MB THERE ISN`T MUCH MOISTURE AT ALL AND
NEGLIGIBLE FORCING. ALL THAT I SEE WEDNESDAY NIGHT INTO THURSDAY
MORNING IS A TRANSITION FROM MAY SOME RAIN OR MORE LIKELY DRIZZLE TO
FREEZING DRIZZLE OVERNIGHT INTO EARLY THURSDAY MORNING. THE
REMAINDER OF THURSDAY INTO FRIDAY WILL BE COLD BUT DRY WITH COLD
AIR CONTINUING TO FUNNEL INTO THE REGION THROUGH THE WEEKEND.
&&
.AVIATION...27/06Z
ISSUED AT 1131 PM CST MON JAN 26 2015
PRIMARY CONCERN REMAINS PROGRESSION OF MVFR/VFR STRATUS THAT
EXTENDS ALONG AND NE OF KEST-KDSM-KTVK LINE AT 06Z WITH PATCH OF
CLEAR SKIES OVER ERN IA FROM KALO-KOTM. MORE WIDESPREAD LOWER CIGS
THEN EXTEND ALL THE WAY BACK INTO MN...WI AND IL IN BROAD
CYCLONIC FLOW. NONE OF THE MODELS SEEM TO HAVE A GREAT HANDLE
ON CURRENT CONDITIONS ACROSS IA...BUT ALL MODELS SEEM TO SLIDE
THE STRATUS SLOWLY SOUTH AND WEST INTO TUE MORNING. THERE IS HIGH
CONFIDENCE THAT AT LEAST PATCHY MVFR CIGS WILL OOZE SW THROUGH IA...BUT
DURATION CONFIDENCE IS LOW. HAVE LEFT ENDING TIME AT 16Z UNTIL
EXIT TRENDS BECOME MORE CLEAR. RAP AND NAM SUGGEST IN SIMILAR
LOCATIONS WILL INTO TUE...WHILE HIGH RES NMM/ARW MODELS ARE MORE
OPTIMISTIC.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...DONAVON
LONG TERM...FAB
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS JACKSON KY
419 AM EST TUE JAN 27 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM EST TUE JAN 27 2015
07Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE OFF TO THE
NORTHEAST WHILE LOCALLY THE PRESSURE GRADIENT IS RATHER RELAXED AND
THIS IS LIMITING THE UPSLOPE COMPONENT OF THIS NIGHT/S SNOW THREAT.
THE MAIN BANDS OF SNOW ARE BEING PRIMARILY DRIVEN BY A SFC TROUGH
AXIS SPLITTING THE STATE AND A STREAM OF MID LEVEL ENERGY RUNNING
NORTH NORTHWEST TO THE SOUTH SOUTHEAST OVER PARTS OF CENTRAL AND
EASTERN KENTUCKY. ON RADAR...THIS BAND LINES UP WELL WITH THIS
ENERGY STREAM AND IS ALSO ABLE TO TAP INTO EXTRA MOISTURE FROM LAKE
MICHIGAN. THE SNOW ASSOCIATED WITH THIS HAS BEEN RELATIVELY LIGHT
WITH MOST SITES REPORTING SNOW SEEING 4SM OR BETTER VIS...THOUGH IT
IS LIKELY THAT UNDER THE HIGHEST RADAR RETURNS VIS IS LESS THAN 2
MILES. FOR THESE LOCATIONS...A COUPLE OF TENTHS OF AN INCH OR SO OF
ACCUMULATION WILL BE POSSIBLE WHILE MOST OTHER PLACES WILL SEE JUST A
THICK DUSTING OR LESS. AN SPS IS IN EFFECT FOR THIS AND IT WILL BE
CONTINUED THROUGH DAWN AND THE MORNING RUSH HOUR FOR GOOD MEASURE.
TEMPERATURES...MEANWHILE ARE IN THE MID TO UPPER 20S ACROSS THE AREA
WITH DEWPOINTS A DEGREE OR SO LOWER AND WINDS LIGHT TO CALM.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST AS A CLOSED LOW DEEPENS OFF THE NEW ENGLAND COAST AND
A STREAM OF ENERGY FLOWS NNW TO SSE OVER KENTUCKY AND INTO THE
BROADER EAST COAST TROUGH TODAY. THIS FLOW WILL BE NUDGED EAST BY A
MODERATELY STRONG RIDGE IN THE SOUTHERN STREAM CROSSING THE SOUTHERN
PLAINS LATER TONIGHT. THIS RIDGE WILL BE PUSHED SOUTH BY A DEVELOPING
TROUGH COMING OUT OF THE CENTRAL ROCKIES AND MOVING INTO THE CENTRAL
PLAINS LATER WEDNESDAY. GIVEN THE GOOD MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE FIRST PART OF THE
FORECAST AND A BLEND THEREAFTER.
SENSIBLE WEATHER WILL FEATURE A BATCH OF EARLY MORNING SNOW SHOWERS
TARGETING MAINLY THE CUMBERLAND VALLEY OF EASTERN KENTUCKY. A FEW
FLURRIES WILL THEN LINGER INTO EARLY AFTERNOON FOR FAR SOUTHEAST
PARTS OF THE CWA BEFORE ALSO COMING TO AN END BY EARLY EVENING AS THE
CLOUDS ATTEMPT TO CLEAR. THIS...ALONG WITH SOME CONTINUED CAA FROM
THE EAST COAST STORM...WILL MAKE FOR A CHILLY NIGHT WITH LOWS IN THE
TEENS FOR WEDNESDAY MORNING. DESPITE HIGH PRESSURE PASSING THROUGH...
A BATCH OF LOW CLOUDS COULD DEVELOP OVERNIGHT AND HUG OUR EASTERN
ZONES INTO DAWN WEDNESDAY...WHICH MAY SPARE THESE AREAS THE COLDEST
TEMPS. THIS LOW LEVEL MOISTURE WILL ALSO NEED TO BE WATCHED FOR A
POTENTIAL OF SPOTTY FREEZING DRIZZLE IF THE STRATUS GETS THICK
ENOUGH. FOR NOW...THOUGH...IT LOOKS LIKE THIS WILL NOT BE THE
CASE...BUT THE POTENTIAL IS THERE. OTHERWISE...THE APPROACH OF
ANOTHER NORTHERN PASSING SFC LOW WILL HELP TO WARM THE AREA UP ON
WEDNESDAY WITH TEMPS REBOUNDING INTO THE MID 30S NORTHEAST TO THE
LOWER 40S SOUTHWEST. HOWEVER...HIGH CLOUDS WILL START TO MOVE IN BY
AFTERNOON FROM THE NORTHWEST LIMITING SUNSHINE ONCE ANY LOW CLOUDS
BREAK UP.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THIS AFTERNOON BEFORE PLUGGING IN THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR...TERRAIN BASED...
ADJUSTMENTS TO HOURLY AND MINIMUM TEMPERATURES TONIGHT. AS FOR
POPS...ENDED UP CLOSE TO A COMBINATION OF THE WETTER MAV AND DRIER
MET TODAY WHILE AGREED WITH THE LOW POPS FROM ALL GUIDANCE TONIGHT
AND WEDNESDAY ACROSS EAST KENTUCKY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 AM EST TUE JAN 27 2015
THE PERIOD BEGINS WITH HIGH PRESSURE CENTERED TO THE NORTH AND EAST
WITH SOME WEAK UPPER LEVEL RIDGING ACROSS THE REGION. EYES TURN
QUICKLY TO APPROACHING SURFACE LOW ACROSS THE MIDWEST THAT IS
FORECAST TO PROGRESS EAST INTO THE GREAT LAKES. A COLD FRONT
EXTENDING SOUTH FROM THE LOW WILL BE THE DRIVER FOR CHANCES OF PRECIP
AS WE MOVE INTO THURSDAY MORNING INTO THURSDAY NIGHT. THEREFORE
WEDNESDAY NIGHT WILL BE MET WITH INCREASING CLOUDS AND CHANCES OF
PRECIP INCREASING AS WE MOVE TOWARD DAYLIGHT ON THURSDAY. THE PRECIP
WILL BRING A CHANCES OF SNOW OR RAIN/SNOW MIX THURSDAY MORNING BEFORE
CHANGING TO ALL RAIN LATE MORNING INTO THURSDAY AS WARMER AIR MAKES
ITS WAY INTO THE REGION. THIS IS ALSO EVIDENT IN THE SOUNDS AS DRYER
AIR IS SEEN IN THE UPPER LEVEL LEADING TO LESS ICE BY THURSDAY
AFTERNOON. OTHERWISE THIS LOW PRESSURE SYSTEM AND ASSOCIATED
SHORTWAVE WILL MOVE EAST THURSDAY NIGHT WITH LOW DEEPENING ACROSS THE
NORTHEAST US. HERE WE SWITCH TO WEST TO NORTHWEST FLOW AND THEREFORE
HAVE KEPT SOME POPS ACROSS EAST AND SOUTHEAST THURSDAY NIGHT INTO
EARLY FRIDAY. THIS WILL LIKELY MIX WITH OR CHANGE TO SNOW AS WE MOVE
THROUGH THE NIGHT. GIVEN LIMITED MOISTURE AT THIS POINT WOULD THINK
LITTLE TO ANY ACCUMULATIONS WOULD BE EXPECTED WITH BEST CHANCES
ACROSS THE HIGHER TERRAIN.
MOVING INTO FRIDAY EXPECT DECREASING CLOUDS AND HIGH PRESSURE TO DROP
SOUTH OUT OF THE UPPER PLAINS. THIS WILL USHER IN GENERALLY BELOW
NORMAL TEMPS FOR FRIDAY. THE QUESTION REMAINS FRIDAY NIGHT AS TO HOW
MUCH THE TEMPS BOTTOM OUT. RIGHT NOW WOULD SEEM LIKE BEST CHANCES FOR
DECOUPLING WOULD BE ACROSS THE NORTH AND FAR EASTERN PORTIONS OF THE
CWA. DID INTRODUCE SOME TEENS TO BETTER MATCH NEIGHBORING OFFICES.
AFTER THIS THE HIGH PRESSURE MOVES EAST WITH RETURN FLOW SATURDAY
WITH TEMPERATURES GENERALLY ABLE TO REBOUND INTO THE UPPER 30S TO
LOWER 40S.
THEN FOCUS SHIFTS TO NEXT SYSTEM DEVELOPING ACROSS THE SOUTHWEST US
AND PLAINS STATES. THIS LOW PRESSURE WILL EVENTUALLY GET PICK UP BY
NORTHERN STREAM SHORTWAVE AND PROGRESS EAST INTO THE MISSISSIPPI
RIVER VALLEY LATE SATURDAY NIGHT. WE DO INTRODUCE SLIGHT TO CHANCE
POPS SATURDAY NIGHT WITH SOME OF THIS MIXING WITH SNOW AND RAIN
BEFORE CHANGING TO ALL RAIN SUNDAY AS LOW PRESSURE DEEPENS ALONG AND
NEAR THE OHIO RIVER VALLEY THROUGH THE DAY SUNDAY. THIS RAIN WILL
ONCE AGAIN TRANSITION TO MIX AND SNOW SUNDAY EVENING AND SUNDAY
NIGHT FROM NORTH TO SOUTH AS COLDER AIR FILTERS INTO THE REGION
BEHIND THIS LOW. GIVEN THE MORE NORTHERN TRACK OF THIS SURFACE LOW
AND BEST QPF AHEAD OF COLDER AIR WOULD THINK THAT ACCUMULATIONS WOULD
BE LIGHT IN TERMS OF ANY SNOW WE ARE ABLE TO GET. KEEP IN MIND THIS
IS STILL IN THE FARTHER REACHES OF THE LONG TERM FORECAST AND WILL
HAVE TO BE FINE TUNED AS WE GET CLOSER TO THE EVENT. AFTER THIS
SYSTEM MOVES EAST WITH SOME NW FLOW SNOW SHOWERS CONTINUING ACROSS
THE EAST AND SOUTHEAST. OTHERWISE COLDER AIR CONTINUES TO FILTER INTO
THE REGION WITH TEMPERATURES STRUGGLING TO MAKE IT ABOVE FREEZING
MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1245 AM EST TUE JAN 27 2015
A STREAM OF SHORTWAVE ENERGY ALOFT WILL KEEP THE CHANCES OF SNOW IN
THE FORECAST THROUGH MID MORNING TUESDAY FOR EASTERN KENTUCKY. THE
EARLIER BAND OF LIGHT SNOW SET UP MAINLY OVER THE SOUTHWEST PORTION
OF EAST KENTUCKY...BUT THE NEXT BATCH LOOKS TO PASS THROUGH THE AREA
MORE TO THE NORTHEAST OF THE FIRST WITH A BETTER CHANCE OF AFFECTING
THE LOZ AND JKL TAF SITES. HAVE UPDATED THESE TWO WITH SOME MVFR CIGS
AND VIS EXPECTED FOR THE REST OF THE NIGHT IN OFF AND ON SNOW
SHOWERS. THE REST OF THE AREA WILL LIKELY REMAIN WITH MVFR OR NEAR
MVFR CIGS ALONG WITH OCCASIONAL FLURRIES AND AN ODD SNOW SHOWER OR
TWO. HAVE KEPT THE SYM AND SJS WITH JUST A VCSH MENTION DUE TO ALL
GUIDANCE AND TRENDS KEEPING THE BETTER SNOW TO THE SOUTHWEST THROUGH
DAWN. THE LOWER CLOUDS WILL BREAK UP IN MOST PLACES BY MID MORNING
WITH IMPROVING VFR CONDITIONS ANTICIPATED FOR THE AFTERNOON
SPREADING FROM WEST TO EAST ACROSS THE FORECAST AREA. WINDS WILL
GENERALLY BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
335 AM EST TUE JAN 27 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM EST TUE JAN 27 2015
07Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE OFF TO THE
NORTHEAST WHILE LOCALLY THE PRESSURE GRADIENT IS RATHER RELAXED AND
THIS IS LIMITING THE UPSLOPE COMPONENT OF THIS NIGHT/S SNOW THREAT.
THE MAIN BANDS OF SNOW ARE BEING PRIMARILY DRIVEN BY A SFC TROUGH
AXIS SPLITTING THE STATE AND A STREAM OF MID LEVEL ENERGY RUNNING
NORTH NORTHWEST TO THE SOUTH SOUTHEAST OVER PARTS OF CENTRAL AND
EASTERN KENTUCKY. ON RADAR...THIS BAND LINES UP WELL WITH THIS
ENERGY STREAM AND IS ALSO ABLE TO TAP INTO EXTRA MOISTURE FROM LAKE
MICHIGAN. THE SNOW ASSOCIATED WITH THIS HAS BEEN RELATIVELY LIGHT
WITH MOST SITES REPORTING SNOW SEEING 4SM OR BETTER VIS...THOUGH IT
IS LIKELY THAT UNDER THE HIGHEST RADAR RETURNS VIS IS LESS THAN 2
MILES. FOR THESE LOCATIONS...A COUPLE OF TENTHS OF AN INCH OR SO OF
ACCUMULATION WILL BE POSSIBLE WHILE MOST OTHER PLACES WILL SEE JUST A
THICK DUSTING OR LESS. AN SPS IS IN EFFECT FOR THIS AND IT WILL BE
CONTINUED THROUGH DAWN AND THE MORNING RUSH HOUR FOR GOOD MEASURE.
TEMPERATURES...MEANWHILE ARE IN THE MID TO UPPER 20S ACROSS THE AREA
WITH DEWPOINTS A DEGREE OR SO LOWER AND WINDS LIGHT TO CALM.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST AS A CLOSED LOW DEEPENS OFF THE NEW ENGLAND COAST AND
A STREAM OF ENERGY FLOWS NNW TO SSE OVER KENTUCKY AND INTO THE
BROADER EAST COAST TROUGH TODAY. THIS FLOW WILL BE NUDGED EAST BY A
MODERATELY STRONG RIDGE IN THE SOUTHERN STREAM CROSSING THE SOUTHERN
PLAINS LATER TONIGHT. THIS RIDGE WILL BE PUSHED SOUTH BY A DEVELOPING
TROUGH COMING OUT OF THE CENTRAL ROCKIES AND MOVING INTO THE CENTRAL
PLAINS LATER WEDNESDAY. GIVEN THE GOOD MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE FIRST PART OF THE
FORECAST AND A BLEND THEREAFTER.
SENSIBLE WEATHER WILL FEATURE A BATCH OF EARLY MORNING SNOW SHOWERS
TARGETING MAINLY THE CUMBERLAND VALLEY OF EASTERN KENTUCKY. A FEW
FLURRIES WILL THEN LINGER INTO EARLY AFTERNOON FOR FAR SOUTHEAST
PARTS OF THE CWA BEFORE ALSO COMING TO AN END BY EARLY EVENING AS THE
CLOUDS ATTEMPT TO CLEAR. THIS...ALONG WITH SOME CONTINUED CAA FROM
THE EAST COAST STORM...WILL MAKE FOR A CHILLY NIGHT WITH LOWS IN THE
TEENS FOR WEDNESDAY MORNING. DESPITE HIGH PRESSURE PASSING THROUGH...
A BATCH OF LOW CLOUDS COULD DEVELOP OVERNIGHT AND HUG OUR EASTERN
ZONES INTO DAWN WEDNESDAY...WHICH MAY SPARE THESE AREAS THE COLDEST
TEMPS. THIS LOW LEVEL MOISTURE WILL ALSO NEED TO BE WATCHED FOR A
POTENTIAL OF SPOTTY FREEZING DRIZZLE IF THE STRATUS GETS THICK
ENOUGH. FOR NOW...THOUGH...IT LOOKS LIKE THIS WILL NOT BE THE
CASE...BUT THE POTENTIAL IS THERE. OTHERWISE...THE APPROACH OF
ANOTHER NORTHERN PASSING SFC LOW WILL HELP TO WARM THE AREA UP ON
WEDNESDAY WITH TEMPS REBOUNDING INTO THE MID 30S NORTHEAST TO THE
LOWER 40S SOUTHWEST. HOWEVER...HIGH CLOUDS WILL START TO MOVE IN BY
AFTERNOON FROM THE NORTHWEST LIMITING SUNSHINE ONCE ANY LOW CLOUDS
BREAK UP.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THIS AFTERNOON BEFORE PLUGGING IN THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR...TERRAIN BASED...
ADJUSTMENTS TO HOURLY AND MINIMUM TEMPERATURES TONIGHT. AS FOR
POPS...ENDED UP CLOSE TO A COMBINATION OF THE WETTER MAV AND DRIER
MET TODAY WHILE AGREED WITH THE LOW POPS FROM ALL GUIDANCE TONIGHT
AND WEDNESDAY ACROSS EAST KENTUCKY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 356 PM EST MON JAN 26 2015
THE EXTENDED PERIOD BEGINS WITH A TROUGH EXITING TO OUR EAST AS SHORTWAVE
RIDGING BUILDS INTO EASTERN KENTUCKY. THIS RIDGING SHOULD PROVIDE A
TEMPORARY RELIEF OF PRECIP WEDNESDAY AFTERNOON INTO THURSDAY
MORNING. BY 12Z THURSDAY... BOTH GFS/ECMWF SHOW A LOW PRESSURE
SYSTEM CLIPPING NORTHERN KENTUCKY AND LIFTING NEWD FROM THE OHIO
VALLEY TOWARDS NEW ENGLAND... WITH THE GFS PROVIDING MORE SUPPORT
FOR THE MORE ROBUST ECMWF SOLUTION. ANOTHER LULL IN PRECIP FOLLOWS
UNTIL SUNDAY MORNING. AT THAT POINT... MODELS DEPICT A LARGE CLOSED
LOW IN THE SOUTHERN STREAM...OPENING UP AND SPILLING ITS ENERGY EAST
INTO THE FLOW RIDGING OVER THE TENNESSEE VALLEY. THE MODELS CONTINUE
TO SHOW SOME CONNECTION TO THE NORTHERN AND SOUTHERN STREAMS WHICH
WOULD CERTAINLY MAKE THINGS MORE INTERESTING FOR THE UPCOMING
WEEKEND IF THAT PANS OUT. FOR NOW... WILL SHOW ONLY LIMITED
INTERACTION AND EASE INTO A MORE DYNAMIC SCENARIO GIVEN THE
UNCERTAINTY AND LACK OF MODEL RUN TO RUN CONSISTENCY WITH THIS PART
OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE THE ENDING OF THE UPSLOPE SNOW
SHOWERS/FLURRIES IN THE FAR EAST EARLY WEDNESDAY MORNING WITH SOME
SUNSHINE RETURNING. THE NEXT CLIPPER SYSTEM WILL THEN MOVE INTO THE
OHIO VALLEY ON THURSDAY WITH A CHANCE FOR RAIN AND SNOW ACROSS THE
AREA FRIDAY MORNING. ONLY A BRIEF WINDOW FOR DRYING CAN BE EXPECTED
FROM FRIDAY NIGHT INTO SATURDAY NIGHT BEFORE THE POTENTIAL FOR
MAINLY SNOW ARRIVES FROM THE SOUTHWEST IN FAST LOW AND MID LEVEL
FLOW RIDING ALONG A WEST TO EAST ARCTIC BOUNDARY LYING OVER THE OHIO
VALLEY. THIS BOUNDARY IS EXPECTED TO PUSH ON THROUGH KENTUCKY BY
MONDAY MORNING WITH SNOW CHANCES CONTINUING...MAINLY IN THE
SOUTHERN PARTS OF THE CWA. THIS SYSTEM WILL HAVE TO BE CLOSELY
MONITORED AS MODELS COME INTO BETTER AGREEMENT WITH THE PHASING OF
THE NORTHERN AND SOUTHERN STREAM ENERGY AS WELL AS HOW QUICKLY THE
COLD AIR SETTLES INTO THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1245 AM EST TUE JAN 27 2015
A STREAM OF SHORTWAVE ENERGY ALOFT WILL KEEP THE CHANCES OF SNOW IN
THE FORECAST THROUGH MID MORNING TUESDAY FOR EASTERN KENTUCKY. THE
EARLIER BAND OF LIGHT SNOW SET UP MAINLY OVER THE SOUTHWEST PORTION
OF EAST KENTUCKY...BUT THE NEXT BATCH LOOKS TO PASS THROUGH THE AREA
MORE TO THE NORTHEAST OF THE FIRST WITH A BETTER CHANCE OF AFFECTING
THE LOZ AND JKL TAF SITES. HAVE UPDATED THESE TWO WITH SOME MVFR CIGS
AND VIS EXPECTED FOR THE REST OF THE NIGHT IN OFF AND ON SNOW
SHOWERS. THE REST OF THE AREA WILL LIKELY REMAIN WITH MVFR OR NEAR
MVFR CIGS ALONG WITH OCCASIONAL FLURRIES AND AN ODD SNOW SHOWER OR
TWO. HAVE KEPT THE SYM AND SJS WITH JUST A VCSH MENTION DUE TO ALL
GUIDANCE AND TRENDS KEEPING THE BETTER SNOW TO THE SOUTHWEST THROUGH
DAWN. THE LOWER CLOUDS WILL BREAK UP IN MOST PLACES BY MID MORNING
WITH IMPROVING VFR CONDITIONS ANTICIPATED FOR THE AFTERNOON
SPREADING FROM WEST TO EAST ACROSS THE FORECAST AREA. WINDS WILL
GENERALLY BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
100 AM EST TUE JAN 27 2015
.UPDATE...
ISSUED AT 100 AM EST TUE JAN 27 2015
PER RADAR TRENDS AND THE LATEST HRRR/SREF GUIDANCE...THE LIGHT SNOW
BANDS THAT AFFECTED THE FAR SOUTHWEST PORTION OF THE CWA EARLIER IN
THE EVENING WILL SHIFT A BIT MORE TO THE NORTHEAST EARLY THIS
MORNING THESE WILL LIKELY AFFECT MORE OF THE BREADTH OF EASTERN
KENTUCKY AND CONTINUE THROUGH THE EARLY MORNING HOURS...BUT LIKELY NOT
LEAVE MUCH MORE THAN A DUSTING BEHIND IN ANY ONE LOCATION. HOWEVER...
ALREADY COLD ROADS COULD LEAD TO ADDITIONAL SLICK SPOTS INTO DAWN
TUESDAY. HAVE UPDATED THE FORECAST TO FINE TUNE POPS/WX AND SNOW
AMOUNTS THROUGH THE MORNING. ALSO TWEAKED THE T AND TD GRIDS BASED
ON THE LATEST OBS/TRENDS/BCCONSSHORT GUIDANCE THROUGH DAWN. THESE
UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 1100 PM EST MON JAN 26 2015
NO CRUCIAL CHANGES SINCE THE PREVIOUS UPDATE. NEAR TERM TEMPERATURES
CONTINUE TO BE WELL ON TRACK...FRESHENED THEM UP WITH THE LATEST
OBSERVATIONAL DATA...AS WELL AS THE DEW POINTS AND WINDS. FOCUS
CONTINUES TO BE THE SNOW POTENTIAL AS WE HEAD INTO THE OVERNIGHT
HOURS. HRRR HAD A GOOD HANDLE ON THE SNOW EARLIER THIS
EVENING...SHOWING AN EVENTUAL LESSENING AS WE HEADED INTO THE
CURRENT PERIOD. WHILE A FEW LIGHT SNOW SHOWERS AND/OR FLURRIES ARE
LIKELY ONGOING IN PORTIONS OF THE SW CWA...THERE IS A NOTICEABLE
BREAK IN THE WIDESPREAD PRECIP WE HAD OVER CENTRAL KY EARLIER. THAT
BEING SAID...ANOTHER BAND OF ENHANCED PRECIP IS CURRENTLY MAKING ITS
WAY FROM SOUTHERN LAKE MICHIGAN AND SOUTHWARD ACROSS INDIANA. THIS
WILL LIKELY MAKE IT INTO THE CWA OVER THE NEXT FEW HOURS.
UNFORTUNATELY...THE LATEST HRRR HAS A NOTICEABLE LACK IN
INITIALIZATION...AND FURTHERMORE IT IS SHOWING UNLIKELY ARTIFACTS AS
THIS NEXT ROUND OF PRECIP MOVES IN. NOT PUTTING MUCH FAITH INTO THE
HRRR AT THIS POINT FOR THE INCOMING PRECIP. THE LATEST NAM12 AND
ECMWF ALSO PICK UP ON THIS SECOND BAND...THOUGH THE ECMWF LIKELY HAS
THE BETTER HANDLE ON QPF TOTALS. THIS WILL BE THE THING TO MONITOR
FOR POTENTIAL UPDATES THROUGH THE NEXT FEW HOURS.
UPDATE ISSUED AT 658 PM EST MON JAN 26 2015
A BAND OF RADAR REFLECTIVITIES IS CURRENTLY MAKING ITS WAY INTO THE
SW PORTION OF THE CWA. HIGHER REFLECTIVITIES...WHICH HAVE BEEN
REPORTED TO BE PUTTING DOWN SOME QUICK SNOW IS CURRENTLY OVER CENTRAL
KY AND MAKING ITS WAY EASTWARD. WHILE MOST OF THE REFLECTIVITIES OVER
OUR CWA CURRENTLY ARE ONLY PRODUCING FLURRIES...GIVEN THE UPSTREAM
REPORTS...DID GO AHEAD AND INCREASE POPS OVER OUR SW
COUNTIES...BRINGING IN SNOW POTENTIAL A COUPLE HOURS SOONER THAN WAS
PREVIOUSLY FORECAST. ALSO ENDED UP BUMPING UP THE QPF BY A COUPLE
HUNDREDTHS IN THE SW BASED ON THE UPSTREAM REPORTS...BRINGING SNOW
TOTALS UP TO ABOUT HALF AN INCH OVERNIGHT FOR PULASKI...WAYNE...AND
MCCREARY COUNTIES. NEAR TERM TEMPERATURES SEEM TO BE IN FAIRLY GOOD
SHAPE BASED ON THE LATEST INGEST OF OBSERVATIONAL DATA.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 410 PM EST MON JAN 26 2015
AS OF MID TO LATE AFTERNOON...A SHORTWAVE TROUGH IS MOVING EAST OF
THE REGION INTO THE DEVELOPING DEEP TROUGH ACROSS THE EASTERN CONUS.
MEANWHILE THE CLIPPER SYSTEM THAT MOVED ACROSS THE AREA LAST NIGHT
INTO THIS MORNING IS BEGINNING TO REORGANIZE INTO A DEEP
NOR`EASTER/BLIZZARD EAST OF THE MID ATLANTIC STATES. THE REGION WILL
REMAIN UNDER THE INFLUENCE OF NW ALOFT BETWEEN THE DEEPENING TROUGH
ALONG THE EASTERN SEABOARD AND RIDGING EXTENDING FROM MEXICO INTO THE
ROCKIES. AT THE SFC...HIGH PRESSURE WILL ALSO GRADUALLY BUILD INTO THE
GREAT LAKES AND LOWER OH VALLEY REGION ONCE THE CLIPPER SFC LOW
APPROACHING FROM THE OH VALLEY DEPARTS ON TUESDAY.
THE SHORTWAVE TROUGH MOVING INTO WV WILL TAKE THE STEADIER SNOW WITH
IT. LOW LEVEL MOISTURE WILL REMAINS ACROSS THE AREA WITH UPSLOPE
FLOW AND SATURATION IN THE LOW CLOUDS TO COLDER THAN -8C...USUALLY
ENOUGH FOR SMALL SNOWFLAKES OF LIGHT SNOW AND FLURRIES. THE CLIPPER
SYSTEM WILL TRACK TO OUR SW FROM WESTERN KY TO THE SOUTHERN
APPALACHIANS. THIS TRACK WILL FAVOR LOCATIONS ACROSS THE SW PART OF
THE AREA FOR LIGHT SNOW OR SCATTERED SNOW SHOWER CHANCES...ALTHOUGH
MODEL TIME HEIGHT SECTIONS FORM THE NAM AND GFS MODELS DO HAVE A
WINDOW OF RATHER DEEP MOISTURE AND RATHER WEAK OMEGA NEAR 12Z...OR 7
AM ON TUESDAY. SNOW SHOWER CHANCES WILL REMAIN NEAR THE VA BORDER ON
THE UPSLOPE FLOW INTO THIS EVENING...WITH CHANCES FOR SNOW INCREASING
ACROSS THE SOUTHWEST PART OF THE AREA THROUGH THE EVENING AND INTO
THE OVERNIGHT HOURS. DAYTIME HEATING AND COLD TEMPERATURES ALOFT WILL
LEAD TO A CONTINUED CHANCE FOR SNOW SHOWERS AND FLURRIES ON TUESDAY
AND UNTIL THE FLOW BECOMES MORE NORTHERLY LATE TUE INTO TUESDAY
EVENING. QPF WITH THIS WILL BE LIGHT WITH ANY ACCUMULATIONS OF
A HALF AN INCH OR LESS ON AVERAGE WHERE SNOW DOES OCCUR. AN SPS WAS
REISSUED TO HIGHLIGHT THE LIGHT SNOW ACCUMULATION POTENTIAL AND
REFREEZE POTENTIAL THIS EVENING AND TONIGHT.
LOWS TONIGHT WILL BE COLDEST IN THE NORTH AND EAST WHERE 850 MB TEMPS
ARE PROGGED TO BE COLDEST. WE HAVE UNDERCUT MOST GUIDANCE TEMPS ON
AVERAGE ON TUESDAY AS THERE WILL BE SNOW ON THE GROUND IN SOME AREAS
AND MODELS WERE GENERALLY TOO WARM WITH TEMPS TODAY. GRADUAL CLEARING
SHOULD OCCUR FROM LATE TUE INTO TUE NIGHT AND WITH A DRY AIRMASS
PROGGED AND SNOW COVER LIKELY REMAINING IN SOME AREAS...VALLEYS
SHOULD FALL WELL INTO THE TEENS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 356 PM EST MON JAN 26 2015
THE EXTENDED PERIOD BEGINS WITH A TROUGH EXITING TO OUR EAST AS SHORTWAVE
RIDGING BUILDS INTO EASTERN KENTUCKY. THIS RIDGING SHOULD PROVIDE A
TEMPORARY RELIEF OF PRECIP WEDNESDAY AFTERNOON INTO THURSDAY
MORNING. BY 12Z THURSDAY... BOTH GFS/ECMWF SHOW A LOW PRESSURE
SYSTEM CLIPPING NORTHERN KENTUCKY AND LIFTING NEWD FROM THE OHIO
VALLEY TOWARDS NEW ENGLAND... WITH THE GFS PROVIDING MORE SUPPORT
FOR THE MORE ROBUST ECMWF SOLUTION. ANOTHER LULL IN PRECIP FOLLOWS
UNTIL SUNDAY MORNING. AT THAT POINT... MODELS DEPICT A LARGE CLOSED
LOW IN THE SOUTHERN STREAM...OPENING UP AND SPILLING ITS ENERGY EAST
INTO THE FLOW RIDGING OVER THE TENNESSEE VALLEY. THE MODELS CONTINUE
TO SHOW SOME CONNECTION TO THE NORTHERN AND SOUTHERN STREAMS WHICH
WOULD CERTAINLY MAKE THINGS MORE INTERESTING FOR THE UPCOMING
WEEKEND IF THAT PANS OUT. FOR NOW... WILL SHOW ONLY LIMITED
INTERACTION AND EASE INTO A MORE DYNAMIC SCENARIO GIVEN THE
UNCERTAINTY AND LACK OF MODEL RUN TO RUN CONSISTENCY WITH THIS PART
OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE THE ENDING OF THE UPSLOPE SNOW
SHOWERS/FLURRIES IN THE FAR EAST EARLY WEDNESDAY MORNING WITH SOME
SUNSHINE RETURNING. THE NEXT CLIPPER SYSTEM WILL THEN MOVE INTO THE
OHIO VALLEY ON THURSDAY WITH A CHANCE FOR RAIN AND SNOW ACROSS THE
AREA FRIDAY MORNING. ONLY A BRIEF WINDOW FOR DRYING CAN BE EXPECTED
FROM FRIDAY NIGHT INTO SATURDAY NIGHT BEFORE THE POTENTIAL FOR
MAINLY SNOW ARRIVES FROM THE SOUTHWEST IN FAST LOW AND MID LEVEL
FLOW RIDING ALONG A WEST TO EAST ARCTIC BOUNDARY LYING OVER THE OHIO
VALLEY. THIS BOUNDARY IS EXPECTED TO PUSH ON THROUGH KENTUCKY BY
MONDAY MORNING WITH SNOW CHANCES CONTINUING...MAINLY IN THE
SOUTHERN PARTS OF THE CWA. THIS SYSTEM WILL HAVE TO BE CLOSELY
MONITORED AS MODELS COME INTO BETTER AGREEMENT WITH THE PHASING OF
THE NORTHERN AND SOUTHERN STREAM ENERGY AS WELL AS HOW QUICKLY THE
COLD AIR SETTLES INTO THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1245 AM EST TUE JAN 27 2015
A STREAM OF SHORTWAVE ENERGY ALOFT WILL KEEP THE CHANCES OF SNOW IN
THE FORECAST THROUGH MID MORNING TUESDAY FOR EASTERN KENTUCKY. THE
EARLIER BAND OF LIGHT SNOW SET UP MAINLY OVER THE SOUTHWEST PORTION
OF EAST KENTUCKY...BUT THE NEXT BATCH LOOKS TO PASS THROUGH THE AREA
MORE TO THE NORTHEAST OF THE FIRST WITH A BETTER CHANCE OF AFFECTING
THE LOZ AND JKL TAF SITES. HAVE UPDATED THESE TWO WITH SOME MVFR CIGS
AND VIS EXPECTED FOR THE REST OF THE NIGHT IN OFF AND ON SNOW
SHOWERS. THE REST OF THE AREA WILL LIKELY REMAIN WITH MVFR OR NEAR
MVFR CIGS ALONG WITH OCCASIONAL FLURRIES AND AN ODD SNOW SHOWER OR
TWO. HAVE KEPT THE SYM AND SJS WITH JUST A VCSH MENTION DUE TO ALL
GUIDANCE AND TRENDS KEEPING THE BETTER SNOW TO THE SOUTHWEST THROUGH
DAWN. THE LOWER CLOUDS WILL BREAK UP IN MOST PLACES BY MID MORNING
WITH IMPROVING VFR CONDITIONS ANTICIPATED FOR THE AFTERNOON
SPREADING FROM WEST TO EAST ACROSS THE FORECAST AREA. WINDS WILL
GENERALLY BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...JP
LONG TERM...JVM
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
321 AM EST TUE JAN 27 2015
.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY OVERNIGHT AS IT
TRACKS NORTH NORTHEAST OFF THE MID ATLANTIC AND NEW ENGLAND
COASTS. THE LOW WILL MOVE INTO THE CANADIAN MARITIMES ON
WEDNESDAY...AS HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC.
A COLD FRONT WILL CROSS THE AREA THURSDAY NIGHT...FOLLOWED BY HIGH
PRESSURE THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE AS OF 10 PM EST...
NO CHANGES TO THE INHERITED WSW HEADLINES THIS EVENING...ALTHOUGH
CONFIDENCE IN SEEING MORE THAN AN INCH OF SNOW WITHIN THE ENTIRE
WSW IS LOW. LATEST OPERATIONAL 00Z NAM REMAINS LESS THAN IMPRESSED
WITH POTENTIAL SNOWFALL ACCUMULATIONS THRU TUESDAY MORNING. OUTSIDE
OF THE BATCH OF RAIN MOVING SOUTH OVER THE CHES BAY/EASTERN SHORE
ATTM...THE NAM AND LATEST HRRR ARE VOID OF ANY OTHER ORGANIZED
AREAS OF PCPN. AT LEAST WE HAVE BEGUN TO SEE SIGNS OF LIGHT SNOW
DEVELOPING ACROSS THE PIEDMONT/I-95 CORRIDOR THIS EVENING AS
COLDER AIR ALOFT...ASSOCIATED WITH THE APPROACHING UPPER
TROUGH...CONTINUES TO MOVE IN. HOWEVER...OTHER THAN COUNTING ON
THE UPPER TROUGH ITSELF TO GENERATE MEANINGFUL SNOW SHOWERS
OVERNIGHT/TUES MORNING...THE AREA WILL REMAIN TO FAR REMOVED FROM
THE DEEPENING SFC LOW OFFSHORE FOR SIGNIFICANT SNOW. HAVE CONTINUED TO
TRIM SNOW ACCUMULATION WORDING IN THE WSW`S THIS EVENING...AS A
COATING/HALF INCH OF SNOW MAY BE ABOUT THE WORST CASE SCENARIO
MOST PLACES. WILL MAINTAIN GENERALLY 2-3" ON THE LOWER MD EASTERN
SHORE CLOSEST TO THE SFC LOW...BUT A FURTHER REDUCTION IN SNOW
TOTALS MAY BE NECESSARY ON THE NEXT SHIFT. LOWS TONIGHT IN THE UPR
20S NW TO THE MID 30S SE. GRADUALLY IMPROVING CONDITIONS LATER
TUES MORNING INTO THE AFTERNOON.
PREVIOUS DISCUSSION...
MAIN FORECAST CHANGE WAS TO START TRIMMING BACK ON INHERITED
WINTER WX ADVSRYS AS THE LIKELIHOOD FOR 1-3IN OF SNOW HAS DECREASED
OVER MANY AREAS. WPC AND MUCH OF 12Z GUIDANCE SUPPORT THIS
IDEA...WITH THE BEST CHANCE FOR ADVSRY-LEVEL SNOWFALL STILL OVER
THE LWR MD ERN SHORE WHERE 2-4IN IS PSBL. DO NOT THINK NORFOLK AND
RICHMOND METRO AREAS WILL RECEIVE AOA 2IN...BUT WITH THE HEADLINE
ALREADY OUT AND THE POTENTIAL FOR UP TO AN INCH TO PSBLY CAUSE
SOME IMPACTS DURING THE MORNING COMMUTE...WILL KEEP THOSE AREAS
(AND AREAS N AND E) IN THE ADVSRY FOR NOW. ANOTHER ISSUE IS
TEMPS...WITH PARTS OF THE AREA STAYING JUST A TAD ABOVE FREEZING.
WILL UPDATE AS NEEDED THIS EVENG AND TNGT.
AS FOR PCPN...EXPECT MAINLY DRY CONDS DURING THE NEXT FEW HRS
ASIDE FM WORCESTER CNTY WHERE AN AREA OF RA HAS BEEN PERSISTENT.
BETTER CHANCE FOR RAIN ARRIVES THIS EVENG AS SFC LO PRES DEVELOPS
OFFSHORE. POPS RANGE FM 40-50% SW TO 70-80% NE. THE RA WILL
TRANSITION TO A RA/SN MIX THEN SN FM NW TO SE TNGT. TOTAL QPF WILL
BE UP TO A QUARTER INCH. LO TEMPS WILL RANGE FM THE UPR 20S FAR
NW TO MID 30S SE. PCPN WILL END FM W TO E ON TUE AS THE SFC LO
ADVANCES TOWARDS THE GULF OF ME AND NW CAA FLOW LEADS TO GUSTS TO
25-30 MPH NR THE CST AND LWR ERN SHORE. HI TEMPS ONLY IN THE MID
30S TO LWR 40S UNDER A CLOUDY-MSTLY CLOUDY SKY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED CSTL LO PULLS TOWARDS THE CANADIAN
MARITIMES AS SFC HI PRES SLOWLY BLDS IN FM THE W. EXPECT
DECREASING CLOUDS TUE NIGHT WITH NW WINDS. LO TEMPS WILL RANGE
THRU THE 20S...WITH WIND CHILLS IN THE TEENS IN MOST LOCATIONS.
COOL TEMPS INTO WED AS WELL...WITH HIGHS ONLY RANGING FM THE MID
30S OVER THE LWR ERN SHORE TO THE UPR 30S TO LWR 40S ELSEWHERE.
DRY AGAIN FOR WED NIGHT WITH SIMILAR TEMPS AS TUE NIGHT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. ONE LOW PRESSURE SYSTEM MOVES FROM THE
MIDWEST TO THE NORTHEAST STATES SENDING A COLD FRONT THROUGH THE
AREA LATE THURSDAY NIGHT/EARLY FRIDAY MORNING. A CHC OF RAIN IS IN
THE FORECAST MAINLY FOR THURSDAY NIGHT WITH LIGHT SNOW PSBL FAR NRN
PORTIONS OF THE AREA. HIGH PRESSURE BUILDS IN FROM THE WEST FRIDAY
AND SATURDAY. ANOTHER COLD FRONT APPROACHES FROM THE NW AND THEN
MOVES ACROSS THE REGION LATE SUNDAY. EURO HAS A QUICK MOVING FRONTAL
WAVE MOVE ACROSS THE CAROLINAS LATE SUNDAY AND OUT TO SEA MONDAY.
THERE WILL BE A CHC FOR RAIN OR SNOW WITH THIS SYSTEM BUT CONFIDENCE
FOR SIGNIFICANT WINTER WEATHER IS LOW AT THIS POINT.
HIGH TEMPERATURES ARE FORECAST IN THE UPR 30S AND 40S THURSDAY
LOWERING TO MOSTLY 30S TO AROUND 40 SATURDAY THROUGH MONDAY. LOWS
ARE EXPECTED TO RANGE THROUGH THE 30S FRIDAY MORNING AND MOSTLY 20S
SATURDAY THROUGH MONDAY MORNINGS.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SNOW SHOWERS AFFECTING THE TAF SITES AS OF 06Z (RAIN CHANGING TO
SNOW AT KECG)...WITH EITHER LOW MVFR OR IFR CONDITIONS THROUGHOUT.
SOME VARIABILITY IS ANTICIPATED IN CIGS/VSBYS THROUGH 12Z...WILL
AVG IFR WITH CIGS JUST BELOW 1000 FT AND VSBYS OF 2-3SM. COULD
BRIEFLY SEE LIFR CONDS IN HEAVIER SNOW SHOWERS (PROBABLY MOST
LIKELY AT KORF). GUSTY N/NW WINDS TO AROUND 25 KT AT
ORF/KECG...AROUND 20 KT ELSEWHERE.
CONDITIONS WILL GRADUALLY IMPROVE AFTER 12Z...ALTHOUGH WILL HANG
ONTO IFR CIGS AT MOST SITES THROUGH AROUND 15Z...WITH CIGS LIFTING
TO 1500-2500 FT THEREAFTER. WINDS SHIFT MORE TO THE NW AND REMAIN
GUSTY TO AROUND 20 KT.
OUTLOOK...VFR/DRY WEATHER IS EXPECTED TUE NIGHT THROUGH THU AFTN. A
WEAK SYSTEM MAY DROP CIGS AND VSBYS IN LIGHT RAIN THU NIGHT/EARLY
FRI.
&&
.MARINE...
EXTENDED PERIOD OF SCA HEADLINES FORECAST THRU WEDS.
LOW PRESSURE HAS LOCATED JUST OFF THE NC/VA COAST THIS AFTERNOON.
THE LOW HAS INTENSIFIED SLIGHTLY...RESULTING IN AN UPTICK OF N-NE
WINDS OVER THE WATERS. BEGINNING TO SEE 20 KT GUSTS OVER THE
BAY/LOWER JAMES WITH GUSTS OF 30 TO 35 KT OVER THE NRN COASTAL
WATERS. SEAS HAVE RESPONDED...BUILDING TO 7 FT AT BUOY 44009. WINDS
WILL CONTINUE TO RAMP UP THRU LATE AFTERNOON WITH SOLID SCA
CONDITIONS (GUSTS TO 30 KT) EXPECTED ACROSS ALL WATERS TONIGHT AS
THE LOW INTENSIFIES RAPIDLY AND LIFTS AWAY FROM THE COAST. LOW LEVEL
CAA ALSO INTENSIFIES. GALE CONDITIONS WITH GUSTS UP TO 40 KT
EXPECTED ACROSS THE NRN COASTAL WATERS...CLOSEST TO THE STRONGEST
GRADIENT WINDS AND CAA. SEAS BUILD TO 7 TO 12 FT IN THE NRN WATERS
AND 5 TO 8 FT IN THE SRN WATERS TONIGHT. AS THE LOW LIFTS
AWAY...FLOW BACKS TO THE NW...KEEPING HIGH SEAS FROM REACHING THE
BEACHES. NO HIGH SURF PLANNED ATTM. LITTLE CHANGE TUES AS STRONG NW
FLOW PERSISTS BTWN LOW PRESSURE OFF THE NE COAST AND HIGH PRESSURE
OVER THE OH VALLEY. GALE CONDITIONS PERSIST OVER THE NRN COASTAL
WATERS THRU EARLY TUES EVENING...BEFORE SUBSIDING TO SOLID SCA
CONDITIONS. SEAS SUBSIDE TO 5-8 FT TUES-TUES NIGHT. HIGH PRESSURE
FINALLY BUILDS OVER THE WATERS LATE WEDS...ALLOWING WINDS TO
DIMINISH AOB 15 KT. SEAS SUBSIDE THRU WEDS EVENING. HIGH PRESSURE
REMAINS OVER THE WATERS THURS IN ADVANCE OF THE NEXT CLIPPER FRONT
SET TO CROSS THE WATERS THURS NIGHT.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY FOR OCEAN CITY HAS BEEN CANCELLED...FELL
SHORT OF MINOR FLOODING THRESHOLDS AS WINDS SHIFTED FASTER THAN
EXPECTED FROM ONSHORE E/NE MON AFTN TO OFFSHORE N/NW. DEPARTURES
HAVE BEEN BETWEEN 1.5 AND 2 FT ABOVE ASTRONOMICAL TIDE. MDL
GUIDANCE SHOWS THE UPCOMING TIDE THIS AFTN REACHING ABOVE 4 FT
MLLW...BUT THIS APPEARS WELL OVERDONE GIVEN THE N/NW WIND
DIRECTION AND CURRENT OBS AND TRENDS. NAM- BASED CBOFS GUIDANCE IS
RUNNING ABOUT 2 FT HIGHER THAN REALITY...BUT IN TERMS OF TREND
SHOWS THE TIDE THIS AFTN TO BE SLIGHTLY LOWER THAN THE HIGH TIDE
EARLIER THIS MORNING THAT ONLY PEAKED AT 3.7 FT MLLW. WILL
MONITOR TRENDS THROUGH MID MORNING...BUT WILL NOT ISSUE ANY
COASTAL FLOOD ADVSIORY AT THIS POINT GIVEN THE UNFAVORABLE
OFFSHORE WIND FLOW.
ACRS THE LOWER BAY DEPARTURES ARE ALSO RUNNING AS HIGH AS 1.5 TO 2
FEET...BUT THIS STILL LEADS TO TIDES FALLING AT LEAST 0.5 FT SHY
OF MINOR FLOODING THIS AFTN. DEPARTURES WILL FALL TONIGHT INTO WED
WITH NO FLOODING CONCERNS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MDZ021>025.
NC...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ081-
089>091-093>098.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
VAZ073>078-084>086-099-100.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VAZ063-064-070>072-082-083.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST WEDNESDAY FOR ANZ630>632-
634-654-656-658.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ650-652.
SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ633-
635>638.
&&
$$
SYNOPSIS...JDM/MAS
NEAR TERM...JDM/MAS
SHORT TERM...MAS
LONG TERM...LSA
AVIATION...LKB
MARINE...SAM
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
112 AM EST TUE JAN 27 2015
.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY OVERNIGHT AS IT
TRACKS NORTH NORTHEAST OFF THE MID ATLANTIC AND NEW ENGLAND
COASTS. THE LOW WILL MOVE INTO THE CANADIAN MARITIMES ON
WEDNESDAY...AS HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC.
A COLD FRONT WILL CROSS THE AREA THURSDAY NIGHT...FOLLOWED BY HIGH
PRESSURE THROUGH SATURDAY.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE AS OF 10 PM EST...
NO CHANGES TO THE INHERITED WSW HEADLINES THIS EVENING...ALTHOUGH
CONFIDENCE IN SEEING MORE THAN AN INCH OF SNOW WITHIN THE ENTIRE
WSW IS LOW. LATEST OPERATIONAL 00Z NAM REMAINS LESS THAN IMPRESSED
WITH POTENTIAL SNOWFALL ACCUMULATIONS THRU TUESDAY MORNING. OUTSIDE
OF THE BATCH OF RAIN MOVING SOUTH OVER THE CHES BAY/EASTERN SHORE
ATTM...THE NAM AND LATEST HRRR ARE VOID OF ANY OTHER ORGANIZED
AREAS OF PCPN. AT LEAST WE HAVE BEGUN TO SEE SIGNS OF LIGHT SNOW
DEVELOPING ACROSS THE PIEDMONT/I-95 CORRIDOR THIS EVENING AS
COLDER AIR ALOFT...ASSOCIATED WITH THE APPROACHING UPPER
TROUGH...CONTINUES TO MOVE IN. HOWEVER...OTHER THAN COUNTING ON
THE UPPER TROUGH ITSELF TO GENERATE MEANINGFUL SNOW SHOWERS
OVERNIGHT/TUES MORNING...THE AREA WILL REMAIN TO FAR REMOVED FROM
THE DEEPENING SFC LOW OFFSHORE FOR SIGNIFICANT SNOW. HAVE CONTINUED TO
TRIM SNOW ACCUMULATION WORDING IN THE WSW`S THIS EVENING...AS A
COATING/HALF INCH OF SNOW MAY BE ABOUT THE WORST CASE SCENARIO
MOST PLACES. WILL MAINTAIN GENERALLY 2-3" ON THE LOWER MD EASTERN
SHORE CLOSEST TO THE SFC LOW...BUT A FURTHER REDUCTION IN SNOW
TOTALS MAY BE NECESSARY ON THE NEXT SHIFT. LOWS TONIGHT IN THE UPR
20S NW TO THE MID 30S SE. GRADUALLY IMPROVING CONDITIONS LATER
TUES MORNING INTO THE AFTERNOON.
PREVIOUS DISCUSSION...
MAIN FORECAST CHANGE WAS TO START TRIMMING BACK ON INHERITED
WINTER WX ADVSRYS AS THE LIKELIHOOD FOR 1-3IN OF SNOW HAS DECREASED
OVER MANY AREAS. WPC AND MUCH OF 12Z GUIDANCE SUPPORT THIS
IDEA...WITH THE BEST CHANCE FOR ADVSRY-LEVEL SNOWFALL STILL OVER
THE LWR MD ERN SHORE WHERE 2-4IN IS PSBL. DO NOT THINK NORFOLK AND
RICHMOND METRO AREAS WILL RECEIVE AOA 2IN...BUT WITH THE HEADLINE
ALREADY OUT AND THE POTENTIAL FOR UP TO AN INCH TO PSBLY CAUSE
SOME IMPACTS DURING THE MORNING COMMUTE...WILL KEEP THOSE AREAS
(AND AREAS N AND E) IN THE ADVSRY FOR NOW. ANOTHER ISSUE IS
TEMPS...WITH PARTS OF THE AREA STAYING JUST A TAD ABOVE FREEZING.
WILL UPDATE AS NEEDED THIS EVENG AND TNGT.
AS FOR PCPN...EXPECT MAINLY DRY CONDS DURING THE NEXT FEW HRS
ASIDE FM WORCESTER CNTY WHERE AN AREA OF RA HAS BEEN PERSISTENT.
BETTER CHANCE FOR RAIN ARRIVES THIS EVENG AS SFC LO PRES DEVELOPS
OFFSHORE. POPS RANGE FM 40-50% SW TO 70-80% NE. THE RA WILL
TRANSITION TO A RA/SN MIX THEN SN FM NW TO SE TNGT. TOTAL QPF WILL
BE UP TO A QUARTER INCH. LO TEMPS WILL RANGE FM THE UPR 20S FAR
NW TO MID 30S SE. PCPN WILL END FM W TO E ON TUE AS THE SFC LO
ADVANCES TOWARDS THE GULF OF ME AND NW CAA FLOW LEADS TO GUSTS TO
25-30 MPH NR THE CST AND LWR ERN SHORE. HI TEMPS ONLY IN THE MID
30S TO LWR 40S UNDER A CLOUDY-MSTLY CLOUDY SKY.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED CSTL LO PULLS TOWARDS THE CANADIAN
MARITIMES AS SFC HI PRES SLOWLY BLDS IN FM THE W. EXPECT
DECREASING CLOUDS TUE NIGHT WITH NW WINDS. LO TEMPS WILL RANGE
THRU THE 20S...WITH WIND CHILLS IN THE TEENS IN MOST LOCATIONS.
COOL TEMPS INTO WED AS WELL...WITH HIGHS ONLY RANGING FM THE MID
30S OVER THE LWR ERN SHORE TO THE UPR 30S TO LWR 40S ELSEWHERE.
DRY AGAIN FOR WED NIGHT WITH SIMILAR TEMPS AS TUE NIGHT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. ONE LOW PRESSURE SYSTEM MOVES FROM THE
MIDWEST TO THE NORTHEAST STATES SENDING A COLD FRONT THROUGH THE
AREA LATE THURSDAY NIGHT/EARLY FRIDAY MORNING. A CHC OF RAIN IS IN
THE FORECAST MAINLY FOR THURSDAY NIGHT WITH LIGHT SNOW PSBL FAR NRN
PORTIONS OF THE AREA. HIGH PRESSURE BUILDS IN FROM THE WEST FRIDAY
AND SATURDAY. ANOTHER COLD FRONT APPROACHES FROM THE NW AND THEN
MOVES ACROSS THE REGION LATE SUNDAY. EURO HAS A QUICK MOVING FRONTAL
WAVE MOVE ACROSS THE CAROLINAS LATE SUNDAY AND OUT TO SEA MONDAY.
THERE WILL BE A CHC FOR RAIN OR SNOW WITH THIS SYSTEM BUT CONFIDENCE
FOR SIGNIFICANT WINTER WEATHER IS LOW AT THIS POINT.
HIGH TEMPERATURES ARE FORECAST IN THE UPR 30S AND 40S THURSDAY
LOWERING TO MOSTLY 30S TO AROUND 40 SATURDAY THROUGH MONDAY. LOWS
ARE EXPECTED TO RANGE THROUGH THE 30S FRIDAY MORNING AND MOSTLY 20S
SATURDAY THROUGH MONDAY MORNINGS.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SNOW SHOWERS AFFECTING THE TAF SITES AS OF 06Z (RAIN CHANGING TO
SNOW AT KECG)...WITH EITHER LOW MVFR OR IFR CONDITIONS THROUGHOUT.
SOME VARIABILITY IS ANTICIPATED IN CIGS/VSBYS THROUGH 12Z...WILL
AVG IFR WITH CIGS JUST BELOW 1000 FT AND VSBYS OF 2-3SM. COULD
BRIEFLY SEE LIFR CONDS IN HEAVIER SNOW SHOWERS (PROBABLY MOST
LIKELY AT KORF). GUSTY N/NW WINDS TO AROUND 25 KT AT
ORF/KECG...AROUND 20 KT ELSEWHERE.
CONDITIONS WILL GRADUALLY IMPROVE AFTER 12Z...ALTHOUGH WILL HANG
ONTO IFR CIGS AT MOST SITES THROUGH AROUND 15Z...WITH CIGS LIFTING
TO 1500-2500 FT THEREAFTER. WINDS SHIFT MORE TO THE NW AND REMAIN
GUSTY TO AROUND 20 KT.
OUTLOOK...VFR/DRY WEATHER IS EXPECTED TUE NIGHT THROUGH THU AFTN. A
WEAK SYSTEM MAY DROP CIGS AND VSBYS IN LIGHT RAIN THU NIGHT/EARLY
FRI.
&&
.MARINE...
EXTENDED PERIOD OF SCA HEADLINES FORECAST THRU WEDS.
LOW PRESSURE HAS LOCATED JUST OFF THE NC/VA COAST THIS AFTERNOON.
THE LOW HAS INTENSIFIED SLIGHTLY...RESULTING IN AN UPTICK OF N-NE
WINDS OVER THE WATERS. BEGINNING TO SEE 20 KT GUSTS OVER THE
BAY/LOWER JAMES WITH GUSTS OF 30 TO 35 KT OVER THE NRN COASTAL
WATERS. SEAS HAVE RESPONDED...BUILDING TO 7 FT AT BUOY 44009. WINDS
WILL CONTINUE TO RAMP UP THRU LATE AFTERNOON WITH SOLID SCA
CONDITIONS (GUSTS TO 30 KT) EXPECTED ACROSS ALL WATERS TONIGHT AS
THE LOW INTENSIFIES RAPIDLY AND LIFTS AWAY FROM THE COAST. LOW LEVEL
CAA ALSO INTENSIFIES. GALE CONDITIONS WITH GUSTS UP TO 40 KT
EXPECTED ACROSS THE NRN COASTAL WATERS...CLOSEST TO THE STRONGEST
GRADIENT WINDS AND CAA. SEAS BUILD TO 7 TO 12 FT IN THE NRN WATERS
AND 5 TO 8 FT IN THE SRN WATERS TONIGHT. AS THE LOW LIFTS
AWAY...FLOW BACKS TO THE NW...KEEPING HIGH SEAS FROM REACHING THE
BEACHES. NO HIGH SURF PLANNED ATTM. LITTLE CHANGE TUES AS STRONG NW
FLOW PERSISTS BTWN LOW PRESSURE OFF THE NE COAST AND HIGH PRESSURE
OVER THE OH VALLEY. GALE CONDITIONS PERSIST OVER THE NRN COASTAL
WATERS THRU EARLY TUES EVENING...BEFORE SUBSIDING TO SOLID SCA
CONDITIONS. SEAS SUBSIDE TO 5-8 FT TUES-TUES NIGHT. HIGH PRESSURE
FINALLY BUILDS OVER THE WATERS LATE WEDS...ALLOWING WINDS TO
DIMINISH AOB 15 KT. SEAS SUBSIDE THRU WEDS EVENING. HIGH PRESSURE
REMAINS OVER THE WATERS THURS IN ADVANCE OF THE NEXT CLIPPER FRONT
SET TO CROSS THE WATERS THURS NIGHT.
&&
.TIDES/COASTAL FLOODING...
LOW PRESSURE INTENSIFIES RAPIDLY OFF THE MID-ATLANTIC COAST
OVERNIGHT AND TUESDAY. THE RESULT WILL BE A PERIOD OF STRONG NORTH
TO NORTHWEST WINDS OVER THE WATERS. TIDAL ANOMALIES ARE FORECAST
TO REACH 1.5 TO 2.0 FT IN THE LOWER BAY AND AROUND 2.0 FT FOR THE
COASTAL AREAS OF THE ERN SHORE. MINOR FLOODING THRESHOLDS ARE
ANTICIPATED AT OCEAN CITY INLET...WITH A WATER LEVEL OF AROUND 4.0 FT.
GUIDANCE CONTINUES TO TREND DOWN FROM MODERATE FLOODING...WHICH
MAKES SENSE GIVEN A MORE NORTH TO NORTHWEST WIND DIRECTION. THE
COASTAL FLOOD WATCH HAS BEEN REPLACED WITH A COASTAL FLOOD
ADVISORY.
WATER LEVELS ARE EXPECTED TO REMAIN BELOW MINOR FLOODING THRESHOLDS
IN THE LOWER BAY...BUT WILL REACH SLIGHTLY ABOVE HIGHEST ASTRO
TIDE. ANOTHER PERIOD OF HIGH ANOMALIES ARE EXPECTED AGAIN TUESDAY...BEFORE
ANOMALIES DROP OFF TUE NGT/WED AS THE LOW LIFTS AWAY FROM THE
REGION. AFTER CURRENT ADVISORY ENDS MAY NEED TO PLACE ANOTHER ONE
IN EFFECT FOR THE TUE AFTN HIGH TIDE AT OCEAN CITY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MDZ021>025.
COASTAL FLOOD ADVISORY UNTIL 3 AM EST EARLY THIS MORNING FOR
MDZ025.
NC...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ081-
089>091-093>098.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
VAZ073>078-084>086-099-100.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VAZ063-064-070>072-082-083.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ630>638-
654-656-658.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ650-652.
&&
$$
SYNOPSIS...JDM/MAS
NEAR TERM...JDM/MAS
SHORT TERM...MAS
LONG TERM...LSA
AVIATION...LKB
MARINE...SAM
TIDES/COASTAL FLOODING...AKQ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
502 AM EST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EST TUE JAN 27 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN HI AMPLITUDE RDG OVER THE ROCKIES AND DEEP TROF
OVER THE E SUPPORTING INTENSE WINTER STORM THAT IS IMPACTING NEW
ENGLAND. SHRTWV DIGGING SEWD WITHIN THIS NW FLOW/DEEPER CLDS THAT
CAUSED PERIOD OF SN LAST EVNG ARE NOW SE OF THE AREA...SO LINGERING
LIGHT SN OVER THE CENTRAL CWA IS DIMINISHING WITH THE APRCH OF
SHRTWV RDG AXIS/DNVA/DEEP LYR QVECTOR CNVGC AND DRIER MID LVL AIR
SHOWN ON THE 00Z INL/YPL RAOBS. THESE RAOBS SHOW SOME LLVL MSTR BLO
INVRN...SO PLENTY OF LO CLDS LINGER UPSTREAM OVER NRN MN/NW ONTARIO.
HOWEVER...WITH 00Z H85 TEMP ONLY -5C AT INL...THE INCOMING AIRMASS
IS NOT SUFFICIENTLY COLD TO SUPPORT LES. COLDER AND DRIER LLVL AIR
IS STILL PRESENT TOWARD THE E AND ARCTIC HI PRES IN QUEBEC...WITH
MOCLR SKIES REPORTED EARLY THIS MRNG AT NEWBERRY AND THE SAULT.
MAIN FCST CONCERNS FOR TODAY/TNGT WL BE CLD TRENDS/IMPACT ON TEMPS.
TODAY...UPR MI WL BE DOMINATED BY DNVA/DEEP LYR QVECTOR DVGC
ASSOCIATED WITH APRCHG SHRTWV RDG. SO AFTER ANY LINGERING LIGHT SN
ENDS EARLY THIS MRNG...THE DAY SHOULD BE DRY AS SFC RDG AXIS
EXTENDING WSW FM THE HI CENTER IN QUEBEC SHIFTS OVER THE CWA.
DESPITE THE MID LVL DRYING...LINGERING LLVL MSTR TRAPPED BLO
LOWERING/STRENGTHENING SUBSIDENCE INVRN WL LIKELY MAINTAIN GENERALLY
MOCLDY SKIES...IN LINE WITH UPSTREAM OBS. ONE EXCEPTION SHOULD BE
THE ERN CWA...WHERE LIGHT E WIND WL MAINTAIN THE LLVL DRY AIR AND
ALLOW FOR MOSUNNY SKIES. ANOTHER AREA THAT MAY SEE SOME CLRG IS NEAR
LK SUP OVER THE NW CWA WHERE THE LLVL SW FLOW ON THE NRN FLANK OF
THE SFC RDG AXIS WL DOWNSLOPE AND RESULT IN LOWERING THE INVRN BASE
FURTHER. GOING FCST HI TEMPS MAINLY IN THE 20S...COLDEST OVER THE
E AND WARMEST OVER THE W...LOOK TO BE IN GOOD SHAPE.
TNGT...A SHRTWV IS FCST TO TRACK THRU FAR NRN ONTARIO. ALTHOUGH
LINGERING SHRTWV RDG AXIS WL FORCE THIS DISTURBANCE TO PASS TOO FAR
TO THE N TO BRING PCPN TO ALL BUT FAR NRN LK SUP LATE...AN INCRSG
LLVL ACYC SW FLOW BTWN THE SFC RDG AXIS SLIDING OVER LOWER MI AND
FALLING MSLP IN ONTARIO ASSOCIATED WITH THE PASSING SHRTWV WL ADVECT
SOME DRIER AIR INTO THE CWA. THIS DRYING PLUS MORE LLVL SUBSIDENCE
ASSOCIATED WITH THE STRENGTHENING ACYC FLOW WL LIKELY BREAK UP THE
LO CLDS OVER MUCH OF THE CWA...ESPECIALLY OVER NW NEAR LK SUP WHERE
SW WINDS DOWNSLOPE. OVER THE E...THE SW FLOW OFF LK MI MIGHT DRAW
MORE LO CLDS INTO THAT AREA. DESPITE ANY CLRG OF THE LOWER CLDS...
STRONGER WINDS AND INCRSG MID/HI CLDS ON THE SRN FLANK OF THE
DISTURBANCE PASSING TO THE N WL LIMIT THE DIURNAL TEMP FALL. EXPECT
THE LOWEST MIN TEMPS OVER THE E...WHERE TEMPS WL FALL OFF QUICKLY IN
THE EVNG BEFORE THE WINDS HAVE A CHC TO PICK UP A BIT OR ANY
CLDS ROLL IN LATER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 502 AM EST TUE JAN 27 2015
MUCH OF THIS PERIOD WILL BE IMPACTED BY THE STEADY 500MB LOW OVER E
AND E CANADA. FROM TIME TO TIME IT WILL BE EXTENDING A TROUGH ACROSS
MUCH OF THE E HALF OF THE U.S.
WARMEST DAY THIS PERIOD WILL BE WEDNESDAY...WITH HIGHS GENERALLY 30-
35F ON LIGHT S FLOW. A LOW OVER N HUDSON BAY AND AN ADDITIONAL LOW
ACROSS THE N/CENTRAL PLAINS WILL PUSH A TROUGH OVER LAKE SUPERIOR
WEDNESDAY NIGHT. THIS WILL BRING THE BEST CHANCE OF WIDESPREAD SNOW
THROUGH THE LONG TERM PERIOD. HAVE ADJUSTED THE HWO MESSAGE TO
INCLUDE MAINLY THE TIP OF THE KEWEENAW AND E OF A LINE FROM MQT TO
ESC FOR THE POTENTIAL FOR MODERATE SNOW AMOUNTS. EXACT AMOUNTS VARY
SIGNIFICANTLY DEPENDING ON WHAT MODEL IS USED. FOR EXAMPLE AT KSAW
FOR WEDNESDAY NIGHT BUFKIT IS INDICATING THE POTENTIAL FOR 1-2IN
/00Z AND 06Z MODEL RUNS/. THE GFS IS SHOWING CLOSER TO 4-6IN. TAKING
A LOOK AT THE PRECIP FIELDS...THE 27/00Z ECMWF ALIGNS BETTER WITH
THE NAM WHILE THE CANADIAN IS CLOSER TO THE GFS. WILL CONTINUE A
FCST OF 2-5IN FOR MUCH OF THE CWA FROM WED THROUGH THURSDAY...WITH
ONLY 1-2IN ALONG THE WI BORDER. ONLY LIMITED SNOW IS EXPECTED OVER
THE UPSLOPE N CENTRAL AND E LOCATIONS BAST WEDNESDAY NIGHT/THURSDAY
MORNING.
THE TROUGH WILL WEAKEN THURSDAY/THURSDAY NIGHT AS THE LOW ACROSS THE
PLAINS SHIFTS TO S LOWER MI...AND THE NEW ENGLAND STATES.
HOWEVER...INCREASED N-NNW WINDS THURSDAY AFTERNOON LOOK
REASONABLE...WITH A 30-40KT LLJ SET UP...EXPECT ABOVE 925MB. THIS
WILL BE AS UPPER MI BECOMES STUCK BETWEEN THE EXITING LOW PUSHING
TOWARDS THE LOWER GREAT LAKES AND STRONG HIGH PRESSURE NEARING FROM
THE W. LOOK FOR PATCHY BLOWING SNOW TO DEVELOP THURSDAY ALONG LAKE
SUPERIOR...REDUCING VIS.
FRIDAY INTO EARLY SATURDAY... EXPECT THE HIGH MENTIONED ABOVE OVER
SASKATCHEWAN ON THURSDAY TO SINK ACROSS MN AND W LAKE SUPERIOR
FRIDAY MORNING...AND INTO THE OHIO VALLEY AND MID ATLANTIC STATES
SATURDAY. COLD AIR WILL BE OVERHEAD...WITH HIGHS IN THE LOW TO MID
TEENS FRIDAY. WHILE LOW LEVEL MOISTURE AROUND 800MB AND BELOW WILL
REMAIN TRAPPED UNDER THE LOWERING INVERSION THURSDAY-FRIDAY...AND
THE DGZ WILL BE WITHIN THIS MOISTURE LAYER...NO HEADLINE LES IS
ANTICIPATED. THIS WILL BE EVEN THROUGH SLR VALUES CLIMB BACK TO 20-
25:1. LESS THAN FAVORABLE W-SW WINDS FRIDAY EVENING SHOULD PUSH MUCH
IF NOT ALL OF THE LINGERING LIGHT SNOW SHOWERS BACK INTO LAKE
SUPERIOR. THE DRY WEATHER WILL ONLY BE TEMPORARY.
REST OF SATURDAY... A BRIEF TROUGH OF LOW PRESSURE WILL PUSH ACROSS
LAKE SUPERIOR ON SATURDAY...BEFORE STRONGER HIGH PRESSURE NEARS FROM
CENTRAL CANADA. TIMING THIS TROUGH IS IS STILL A BIT ROUGH...AS THE
GFS/ECMWF/CANADIAN DIFFER BY 6-12HRS. THE 27/00Z CANDIAN AND 26/12Z
ECMWF ARE PRETTY CONSISTANT...WHILE THE 27/00Z GFS IS ON THE SLOW
SIDE. EITHER WAY IT WILL USHER IN ANOTHER ROUND OF COLD AIR. HIGHS
SUNDAY SHOULD TOP OUT 10-17F.
SUNDAY THROUGH MONDAY... STRONGER AND COLD 30.9 INCH/1040-1050MB
HIGH PRESSURE OVER MUCH OF CENTRAL CANADA FRIDAY AND SATURDAY WILL
SLOWLY WEAKEN TO 30.6IN/1033-1037MB AS IT SETTLES ACROSS THE N
PLAINS/ UPPER MS VALLEY/UPPER GREAT LAKES TO START THE NEXT WORK
WEEK. HIGHS MONDAY MAY ONLY BE IN THE SINGLE DIGITS ABOVE ZERO.
THE HIGH WILL CONTINUE TO SINK SE ACROSS THE MID MS VALLEY/OHIO
VALLEY MONDAY NIGHT...AND MID ATLANTIC STATES TUESDAY-WEDNESDAY. THE
GFS IS PERSISTENT IN KEEPING THE HIGH IN PLACE...WHILE THE 26/12Z
ECMWF IS MORE PROGRESSIVE. MORE ON THIS WHEN WE START FCSTING FOR
MID NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1223 AM EST TUE JAN 27 2015
LINGERING LOW-LEVEL MOISTURE WILL KEEP ALL TAF SITES AT IFR TO LOW
MVFR CONDITIONS OVERNIGHT. EXPECT SOME DIURNAL IMPROVEMENT TO
HIGHER END MVFR LATE TUE MORNING INTO THE AFTERNOON UNDER A LIGHT
SOUTHERLY FLOW. VFR CONDITIONS MAY BE POSSIBLE AT KIWD TUE EVENING
AS DRIER AIR WORKS IN FROM THE SOUTH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST TUE JAN 27 2015
EXPECT S TO SW WINDS UNDER 20 KTS TO DOMINATE THRU WED AS A HI PRES
RIDGE OVER UPPER MI TODAY SINKS SLOWLY INTO THE LOWER GREAT LAKES.
ON THE NORTHERN FLANK OF A HI PRES RIDGE ORIENTED ACROSS THE CENTRAL
GREAT LAKES. LO PRES WILL THEN TRACK FROM THE MID MISSISSIPPI VALLEY
WED NIGHT TO THE LOWER LAKES THU NIGHT. BEHIND THE LOW...N TO NW
WINDS WILL INCREASE TO 20-30KT AND THEN TO GALE FORCE LATE THU AND
THU NIGHT. SINCE THESE STRONG WINDS WILL DRAW MUCH COLDER ARCTIC AIR
INTO THE UPPER LAKES...HEAVY FREEZING SPRAY WILL DEVELOP OVER MUCH
OF THE LAKE AND CONTINUE INTO FRI...WHEN WINDS/WAVES WILL DIMINISH
WITH THE CLOSER APPROACH OF CANADIAN HI PRES. ANOTHER DISTURBANCE
AND COLD FRONT MAY SWING ACROSS THE UPPER LAKES ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
409 AM EST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EST TUE JAN 27 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN HI AMPLITUDE RDG OVER THE ROCKIES AND DEEP TROF
OVER THE E SUPPORTING INTENSE WINTER STORM THAT IS IMPACTING NEW
ENGLAND. SHRTWV DIGGING SEWD WITHIN THIS NW FLOW/DEEPER CLDS THAT
CAUSED PERIOD OF SN LAST EVNG ARE NOW SE OF THE AREA...SO LINGERING
LIGHT SN OVER THE CENTRAL CWA IS DIMINISHING WITH THE APRCH OF
SHRTWV RDG AXIS/DNVA/DEEP LYR QVECTOR CNVGC AND DRIER MID LVL AIR
SHOWN ON THE 00Z INL/YPL RAOBS. THESE RAOBS SHOW SOME LLVL MSTR BLO
INVRN...SO PLENTY OF LO CLDS LINGER UPSTREAM OVER NRN MN/NW ONTARIO.
HOWEVER...WITH 00Z H85 TEMP ONLY -5C AT INL...THE INCOMING AIRMASS
IS NOT SUFFICIENTLY COLD TO SUPPORT LES. COLDER AND DRIER LLVL AIR
IS STILL PRESENT TOWARD THE E AND ARCTIC HI PRES IN QUEBEC...WITH
MOCLR SKIES REPORTED EARLY THIS MRNG AT NEWBERRY AND THE SAULT.
MAIN FCST CONCERNS FOR TODAY/TNGT WL BE CLD TRENDS/IMPACT ON TEMPS.
TODAY...UPR MI WL BE DOMINATED BY DNVA/DEEP LYR QVECTOR DVGC
ASSOCIATED WITH APRCHG SHRTWV RDG. SO AFTER ANY LINGERING LIGHT SN
ENDS EARLY THIS MRNG...THE DAY SHOULD BE DRY AS SFC RDG AXIS
EXTENDING WSW FM THE HI CENTER IN QUEBEC SHIFTS OVER THE CWA.
DESPITE THE MID LVL DRYING...LINGERING LLVL MSTR TRAPPED BLO
LOWERING/STRENGTHENING SUBSIDENCE INVRN WL LIKELY MAINTAIN GENERALLY
MOCLDY SKIES...IN LINE WITH UPSTREAM OBS. ONE EXCEPTION SHOULD BE
THE ERN CWA...WHERE LIGHT E WIND WL MAINTAIN THE LLVL DRY AIR AND
ALLOW FOR MOSUNNY SKIES. ANOTHER AREA THAT MAY SEE SOME CLRG IS NEAR
LK SUP OVER THE NW CWA WHERE THE LLVL SW FLOW ON THE NRN FLANK OF
THE SFC RDG AXIS WL DOWNSLOPE AND RESULT IN LOWERING THE INVRN BASE
FURTHER. GOING FCST HI TEMPS MAINLY IN THE 20S...COLDEST OVER THE
E AND WARMEST OVER THE W...LOOK TO BE IN GOOD SHAPE.
TNGT...A SHRTWV IS FCST TO TRACK THRU FAR NRN ONTARIO. ALTHOUGH
LINGERING SHRTWV RDG AXIS WL FORCE THIS DISTURBANCE TO PASS TOO FAR
TO THE N TO BRING PCPN TO ALL BUT FAR NRN LK SUP LATE...AN INCRSG
LLVL ACYC SW FLOW BTWN THE SFC RDG AXIS SLIDING OVER LOWER MI AND
FALLING MSLP IN ONTARIO ASSOCIATED WITH THE PASSING SHRTWV WL ADVECT
SOME DRIER AIR INTO THE CWA. THIS DRYING PLUS MORE LLVL SUBSIDENCE
ASSOCIATED WITH THE STRENGTHENING ACYC FLOW WL LIKELY BREAK UP THE
LO CLDS OVER MUCH OF THE CWA...ESPECIALLY OVER NW NEAR LK SUP WHERE
SW WINDS DOWNSLOPE. OVER THE E...THE SW FLOW OFF LK MI MIGHT DRAW
MORE LO CLDS INTO THAT AREA. DESPITE ANY CLRG OF THE LOWER CLDS...
STRONGER WINDS AND INCRSG MID/HI CLDS ON THE SRN FLANK OF THE
DISTURBANCE PASSING TO THE N WL LIMIT THE DIURNAL TEMP FALL. EXPECT
THE LOWEST MIN TEMPS OVER THE E...WHERE TEMPS WL FALL OFF QUICKLY IN
THE EVNG BEFORE THE WINDS HAVE A CHC TO PICK UP A BIT OR ANY
CLDS ROLL IN LATER.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 437 PM EST MON JAN 26 2015
THERE WILL BE MINOR FLUCTUATIONS IN THE UPPER RIDGE ALONG THE
WESTERN COAST OF NORTH AMERICA...BUT IT WILL LARGELY STAY IN PLACE
THROUGH THE LONG TERM FORECAST. THIS WILL LEAD TO NORTHWESTERLY
FLOW ALOFT OVER THE UPPER GREAT LAKES REGION AND SEND A SERIES OF
SHORTWAVES THROUGH THE AREA.
THE UPPER GREAT LAKES REGION WILL BE UNDER WEAK RIDGING WITHIN THE
NORTHWESTERLY FLOW ALOFT TO START THE PERIOD...WHILE THE SURFACE
RIDGE WILL BE SLIDING EAST OF THE AREA. EXPECT THERE TO BE SOME
LINGERING LOWER CLOUDS OVER THE CENTRAL PART OF THE CWA...WHILE
THERE WILL BE HIGH CLOUDS SPREADING OVER THE WESTERN CWA AHEAD OF
THE NEXT SYSTEM. THESE CLOUDS WILL KEEP TEMPS FROM FALLING TOO MUCH
IN THAT AREA...BUT OVER THE EAST...CLEARING IN THE EVENING WILL
ALLOW TEMPERATURES TO QUICKLY FALL INTO THE LOWER SINGLE DIGITS
ABOVE ZERO. DID TREND TOWARDS THE BETTER PERFORMING GEM MODELS OVER
THE EAST IN THOSE CLEAR SKY AND RADIATIONAL COOLING SITUATIONS.
FOCUS THEN TURNS TO THE INVERTED TROUGH PUSHING EAST TOWARDS THE
AREA ON WEDNESDAY (FROM A LOW MOVING OUT OF THE NORTHERN/CENTRAL
PLAINS) AND THREE SHORTWAVES THAT WILL COME TOGETHER OVER THE GREAT
LAKES REGION THROUGH THURSDAY. THE INITIAL AREA OF PRECIPITATION
SHOULD STAY WELL TO THE NORTH OF UPPER MICHIGAN ON WEDNESDAY (TIED
TO THE DEEPER MOISTURE AND BROAD WARM AIR ADVECTION OVER NORTHERN
LAKE SUPERIOR. BUT AS A SECOND SHORTWAVE SLIDES SOUTHEAST INTO THE
AREA FROM MANITOBA ON WEDNESDAY NIGHT...EXPECT THE PRECIPITATION
SWEEP SOUTH THROUGH THE AREA WITH THE 850-700MB TROUGH. SHOULD SEE
1-3 INCHES OF SNOW MOVE ACROSS THE AREA ON WEDNESDAY NIGHT...WITH
THE HIGHEST AMOUNTS OVER THE EAST. COLDER AIR IS DELAYED BEHIND THE
SYSTEM...SO DON/T EXPECT MUCH IN THE WAY OF LAKE ENHANCEMENT...BUT
DID FACTOR IN SOME TERRAIN ENHANCEMENT FOR THURSDAY. WITH THAT LACK
OF COLD AIR...THE CLOUD THERMAL PROFILE IS ON THE EDGE FOR ICE
CRYSTALS. AT THIS POINT...THINK THERE WILL BE ENOUGH AND LEFT OUT
FREEZING DRIZZLE...BUT IT WILL BE SOMETHING TO WATCH.
THE COLD AIR FINALLY ARRIVES ON THURSDAY NIGHT AND REMAINS INTO
FRIDAY UNDER NORTH-NORTHWEST WINDS ALOFT. EXPECT LIGHT LAKE EFFECT
TO OCCUR IN THOSE SNOW BELTS...BUT WITH SUBSIDENCE FROM HIGH
PRESSURE BUILDING INTO THE UPPER MISSISSIPPI VALLEY...INVERSION
HEIGHTS WILL STRUGGLE TO RISE MUCH ABOVE 4-5KFT. THUS...THINK
ACCUMULATIONS WILL BE ON THE LOW SIDE...BUT THEY WILL BE EFFICIENT
AT REDUCING VISIBILITIES DUE TO THE CLOUD BEING ABOVE THE DGZ.
WINDS WILL BACK ON FRIDAY AFTERNOON/NIGHT AS THE HIGH SLIDES JUST
TO THE SOUTH OF THE AREA.
FORECAST BECOMES A LITTLE UNCERTAIN AS MODELS DIVERGE ON THE UPPER
LEVEL FEATURES. ALL IN ALL...LOOKS LIKE A WEAK TROUGH WILL SLIDE
ACROSS THE AREA ON SATURDAY AND USHER IN ANOTHER SURGE OF COLD AIR
(MID -20S 850MB TEMPS) INTO THE UPPER GREAT LAKES REGION. WILL
CONTINUE TO SHOW LAKE EFFECT POPS BEHIND THAT TROUGH IN THE NW WIND
SNOW BELTS FOR SATURDAY NIGHT INTO MONDAY. WITH THE AMOUNT OF COLD
AIR...EXPECT LIMITED SNOWFALL AMOUNTS BUT GOOD VISIBILITY
RESTRICTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1223 AM EST TUE JAN 27 2015
LINGERING LOW-LEVEL MOISTURE WILL KEEP ALL TAF SITES AT IFR TO LOW
MVFR CONDITIONS OVERNIGHT. EXPECT SOME DIURNAL IMPROVEMENT TO
HIGHER END MVFR LATE TUE MORNING INTO THE AFTERNOON UNDER A LIGHT
SOUTHERLY FLOW. VFR CONDITIONS MAY BE POSSIBLE AT KIWD TUE EVENING
AS DRIER AIR WORKS IN FROM THE SOUTH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST TUE JAN 27 2015
EXPECT S TO SW WINDS UNDER 20 KTS TO DOMINATE THRU WED AS A HI PRES
RIDGE OVER UPPER MI TODAY SINKS SLOWLY INTO THE LOWER GREAT LAKES.
ON THE NORTHERN FLANK OF A HI PRES RIDGE ORIENTED ACROSS THE CENTRAL
GREAT LAKES. LO PRES WILL THEN TRACK FROM THE MID MISSISSIPPI VALLEY
WED NIGHT TO THE LOWER LAKES THU NIGHT. BEHIND THE LOW...N TO NW
WINDS WILL INCREASE TO 20-30KT AND THEN TO GALE FORCE LATE THU AND
THU NIGHT. SINCE THESE STRONG WINDS WILL DRAW MUCH COLDER ARCTIC AIR
INTO THE UPPER LAKES...HEAVY FREEZING SPRAY WILL DEVELOP OVER MUCH
OF THE LAKE AND CONTINUE INTO FRI...WHEN WINDS/WAVES WILL DIMINISH
WITH THE CLOSER APPROACH OF CANADIAN HI PRES. ANOTHER DISTURBANCE
AND COLD FRONT MAY SWING ACROSS THE UPPER LAKES ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1223 AM EST TUE JAN 27 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 434 PM EST MON JAN 26 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN AMPLIFIED PATTERN OVER
NAMERICA...FEATURING A RIDGE OVER THE WRN CONUS INTO SW CANADA AND A
TROF OVER THE E. RESULTING NW FLOW INTO THE GREAT LAKES IS CARRYING
SEVERAL MINOR DISTURBANCES TO THE SE...AND THIS HAS LED TO BKN PCPN
EXTENDING FROM IL/IN NNW INTO NRN ONTARIO PER REGIONAL RADAR
IMAGERY. IR IMAGERY SHOWS ONE DIMINISHING AREA OF ENHANCED CLOUDS
NOW SSE OF UPPER MI AND A SECOND AREA DROPPING SSE TOWARD LAKE
SUPERIOR. THE ENHANCED CLOUDS WITH THE APPROACHING SHORTWAVE HAVE
NOT CHANGED MUCH OVER THE LAST SEVERAL HRS...AND ENVIRONMENT CANADA
RADAR NEAR THUNDER BAY SHOWS A DECENT AREA OF ASSOCIATED SNOW
APPROACHING NW LAKE SUPERIOR. TO THE SE...AN AREA OF ENHANCED
CONVERGENCE OVER LAKE MI AT THE LEADING EDGE OF STRONGER SE WINDS
LED TO SOME SNOW SPREADING OFF LAKE MI INTO DELTA AND ALGER COUNTIES
TODAY. ON VIS SATELLITE IMAGERY...HIGH CLOUDS HAVE THINNED JUST
ENOUGH TO SEE THAT THERE IS LITTLE IN THE WAY OF LAKE EFFECT CLOUDS
REMAINING ON NRN LAKE MI NOW.
SHORTWAVE OFF TO THE NW WILL DIVE SE ACROSS UPPER MI TONIGHT. GIVEN
THE ENHANCED CLOUDS JUST NNW OF THE AREA...SNOW DEPICTED ON UPSTREAM
RADAR IMAGERY NEAR THUNDER BAY AND MODEST DEEP LAYER QVECTOR
CONVERGENCE INDICATED BY MODELS...EXPECT ANOTHER AREA OF STEADIER
-SN TO SPREAD SSE ACROSS THE WRN AND CNTRL FCST AREA THIS EVENING.
ERN EDGE OF THE FORCING WILL BE UP AGAINST A STEADY FEED OF LOW-
LEVEL DRY AIR EMANATING FROM HIGH PRES CENTERED OVER SOUTHERN
QUEBEC. THIS IS CERTAINLY EVIDENT IN NAM/GFS/RUC13 FCST SOUNDINGS
WHICH MAINTAIN A DRY WEDGE IN ROUGHLY THE 2-5KFT LAYER...AND HIGH
RES MODELS SHOW PCPN STAYING W OF ROUGHLY A KISQ/SHINGLETON LINE
WITH ONLY THE GEM GETTING PCPN CLOSE TO KERY. THUS...WILL NOT
INCLUDE ANY SNOW IN THE FCST OVER THE FAR E TONIGHT. THAT SAID...THE
ONLY POTENTIAL ISSUE WOULD BE FOR A COUPLE OF THE LES BANDS OFF NRN
LAKE HURON TO STREAK WNW INTO LUCE COUNTY FOR A TIME TONIGHT. BACK
TO THE W...HIGH RES MODELS SHOW PCPN AMOUNTS IN THE 0.03 TO 0.1 INCH
RANGE TONIGHT...FALLING ALMOST ENTIRELY BEFORE 06Z. WITH SLR
PROBABLY AROUND 17 TO 1...THIS SUGGESTS SNOW AMOUNTS OF 0.5 TO
NEARLY 2 INCHES. WITH LOW-LEVEL SE WINDS PROVIDING
UPSLOPING/MOISTENING OFF LAKE MICHIGAN...THE HIGHER SNOW AMOUNTS
SHOULD OCCUR ROUGHLY IN THE AREA S OF A LINE FROM IRON RIVER TO
NEGAUNEE TO ESCANABA. AS FOR TEMPS...BIGGEST CHALLENGE IS OVER THE
FAR E WHERE CLOUDS MAY THIN OUT ENOUGH LATE IN THE NIGHT FOR TEMPS
TO PLUMMET UNDER LIGHT/CALM WIND. FOR NOW...INDICATED MINS NEAR
ZERO IN THAT AREA.
QUIET DAY ON THE WAY FOR TUE WITH SFC HIGH PRES RIDGE OVER UPPER MI.
WHILE THE E WILL PROBABLY ENJOY A MOSTLY SUNNY DAY...LOW CLOUDS WILL
LIKELY TAKE SOME TIME TO SCATTER OUT OVER THE W AND CNTRL. EXPECT
HIGHS RANGING FROM THE LWR 20S E TO THE UPPER 20S W.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 437 PM EST MON JAN 26 2015
THERE WILL BE MINOR FLUCTUATIONS IN THE UPPER RIDGE ALONG THE
WESTERN COAST OF NORTH AMERICA...BUT IT WILL LARGELY STAY IN PLACE
THROUGH THE LONG TERM FORECAST. THIS WILL LEAD TO NORTHWESTERLY
FLOW ALOFT OVER THE UPPER GREAT LAKES REGION AND SEND A SERIES OF
SHORTWAVES THROUGH THE AREA.
THE UPPER GREAT LAKES REGION WILL BE UNDER WEAK RIDGING WITHIN THE
NORTHWESTERLY FLOW ALOFT TO START THE PERIOD...WHILE THE SURFACE
RIDGE WILL BE SLIDING EAST OF THE AREA. EXPECT THERE TO BE SOME
LINGERING LOWER CLOUDS OVER THE CENTRAL PART OF THE CWA...WHILE
THERE WILL BE HIGH CLOUDS SPREADING OVER THE WESTERN CWA AHEAD OF
THE NEXT SYSTEM. THESE CLOUDS WILL KEEP TEMPS FROM FALLING TOO MUCH
IN THAT AREA...BUT OVER THE EAST...CLEARING IN THE EVENING WILL
ALLOW TEMPERATURES TO QUICKLY FALL INTO THE LOWER SINGLE DIGITS
ABOVE ZERO. DID TREND TOWARDS THE BETTER PERFORMING GEM MODELS OVER
THE EAST IN THOSE CLEAR SKY AND RADIATIONAL COOLING SITUATIONS.
FOCUS THEN TURNS TO THE INVERTED TROUGH PUSHING EAST TOWARDS THE
AREA ON WEDNESDAY (FROM A LOW MOVING OUT OF THE NORTHERN/CENTRAL
PLAINS) AND THREE SHORTWAVES THAT WILL COME TOGETHER OVER THE GREAT
LAKES REGION THROUGH THURSDAY. THE INITIAL AREA OF PRECIPITATION
SHOULD STAY WELL TO THE NORTH OF UPPER MICHIGAN ON WEDNESDAY (TIED
TO THE DEEPER MOISTURE AND BROAD WARM AIR ADVECTION OVER NORTHERN
LAKE SUPERIOR. BUT AS A SECOND SHORTWAVE SLIDES SOUTHEAST INTO THE
AREA FROM MANITOBA ON WEDNESDAY NIGHT...EXPECT THE PRECIPITATION
SWEEP SOUTH THROUGH THE AREA WITH THE 850-700MB TROUGH. SHOULD SEE
1-3 INCHES OF SNOW MOVE ACROSS THE AREA ON WEDNESDAY NIGHT...WITH
THE HIGHEST AMOUNTS OVER THE EAST. COLDER AIR IS DELAYED BEHIND THE
SYSTEM...SO DON/T EXPECT MUCH IN THE WAY OF LAKE ENHANCEMENT...BUT
DID FACTOR IN SOME TERRAIN ENHANCEMENT FOR THURSDAY. WITH THAT LACK
OF COLD AIR...THE CLOUD THERMAL PROFILE IS ON THE EDGE FOR ICE
CRYSTALS. AT THIS POINT...THINK THERE WILL BE ENOUGH AND LEFT OUT
FREEZING DRIZZLE...BUT IT WILL BE SOMETHING TO WATCH.
THE COLD AIR FINALLY ARRIVES ON THURSDAY NIGHT AND REMAINS INTO
FRIDAY UNDER NORTH-NORTHWEST WINDS ALOFT. EXPECT LIGHT LAKE EFFECT
TO OCCUR IN THOSE SNOW BELTS...BUT WITH SUBSIDENCE FROM HIGH
PRESSURE BUILDING INTO THE UPPER MISSISSIPPI VALLEY...INVERSION
HEIGHTS WILL STRUGGLE TO RISE MUCH ABOVE 4-5KFT. THUS...THINK
ACCUMULATIONS WILL BE ON THE LOW SIDE...BUT THEY WILL BE EFFICIENT
AT REDUCING VISIBILITIES DUE TO THE CLOUD BEING ABOVE THE DGZ.
WINDS WILL BACK ON FRIDAY AFTERNOON/NIGHT AS THE HIGH SLIDES JUST
TO THE SOUTH OF THE AREA.
FORECAST BECOMES A LITTLE UNCERTAIN AS MODELS DIVERGE ON THE UPPER
LEVEL FEATURES. ALL IN ALL...LOOKS LIKE A WEAK TROUGH WILL SLIDE
ACROSS THE AREA ON SATURDAY AND USHER IN ANOTHER SURGE OF COLD AIR
(MID -20S 850MB TEMPS) INTO THE UPPER GREAT LAKES REGION. WILL
CONTINUE TO SHOW LAKE EFFECT POPS BEHIND THAT TROUGH IN THE NW WIND
SNOW BELTS FOR SATURDAY NIGHT INTO MONDAY. WITH THE AMOUNT OF COLD
AIR...EXPECT LIMITED SNOWFALL AMOUNTS BUT GOOD VISIBILITY
RESTRICTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1223 AM EST TUE JAN 27 2015
LINGERING LOW-LEVEL MOISTURE WILL KEEP ALL TAF SITES AT IFR TO LOW
MVFR CONDITIONS OVERNIGHT. EXPECT SOME DIURNAL IMPROVEMENT TO
HIGHER END MVFR LATE TUE MORNING INTO THE AFTERNOON UNDER A LIGHT
SOUTHERLY FLOW. VFR CONDITIONS MAY BE POSSIBLE AT KIWD TUE EVENING
AS DRIER AIR WORKS IN FROM THE SOUTH.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 434 PM EST MON JAN 26 2015
WITH WEAK LOW PRES OVER NE MN DROPPING SSE TONIGHT...STRONGER S
WINDS OF 20-30KT WILL CONTINUE OVER ERN LAKE SUEPRIOR THRU THIS
EVENING BEFORE DIMINISHING OVERNIGHT. WITH WEAKER PRES GRADIENT OVER
THE W...WINDS WILL BE UNDER 20KT. WINDS WILL THEN BE UNDER 20KT
ACROSS THE ENTIRE LAKE TUE/WED AS HIGH PRES RIDGE DRIFTS SSE FROM
THE UPPER LAKES. LOW PRES WILL THEN TRACK FROM THE MID MISSISSIPPI
VALLEY WED NIGHT TO THE LOWER LAKES THU NIGHT. BEHIND THE LOW...N TO
NW WINDS WILL INCREASE TO 20-30KT THU/THU NIGHT WITH GALES POSSIBLE
OVER THE E HALF OF THE LAKE. WINDS WILL THEN DIMINISH FRI AS HIGH
PRES PASSES ACROSS THE WRN GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DULUTH MN
332 AM CST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CST TUE JAN 27 2015
HIGH PRESSURE WAS SETTLING OVER THE FORECAST AREA AT 08Z. PLENTY OF
LOW CLOUDS COVERED THE AREA TRAPPED UNDER THE LOW LEVEL INVERSION
FROM THE HIGH. THERE ARE A FEW HOLES THAT OPEN NEAR LAKE
SUPERIOR...BUT NOT ANTICIPATING ANY OF THEM MAKING IT INLAND. IF
THEY DO...THEY WILL FILL IN RATHER QUICKLY. THE HIGH WILL DRIFT
OVER THE CENTRAL GREAT LAKES BY 00Z WEDNESDAY RESULTING IN A SW FLOW
AFFECTING THE AREA. MODELS ARE TRYING TO CLEAR OUT THE CLOUD COVER
SOMEWHAT DURING THE DAY...BUT HAVE OPTED TO HANG ONTO THE CLOUD
COVER THROUGH THE DAY AS 1000-850MB RH REMAINS ABOVE 65 PERCENT.
MODEL DIFFERENCES BEGIN TO CREEP INTO THE FORECAST PROCESS TONIGHT.
BY 06Z...THE ECMWF IS BRINGING SOME LIGHT QPF FROM INL TO THE
ARROWHEAD. OTHER MODELS KEEP THE PRECIPITATION NORTH OF THE CANADIAN
BORDER. HOWEVER...THE HIRES NMM/ARW EAST AND WEST ARE HINTING AT
SOME LIGHT PRECIPITATION...BUT JUST OVER THE ARROWHEAD. WILL USE A
BLENDED APPROACH AND HAVE NO QPF PRIOR TO 06Z. AFTER 06Z...HAVE
INTRODUCED SOME POPS TO THE TIP OF THE ARROWHEAD. THIS IS WHEN SOME
WEAK FRONTOGENESIS IS FOUND FROM 700MB TO 850MB. PTYPE SHOULD BE ALL
SNOW AS SUGGESTED BY THERMAL PROFILES. SNOW AMOUNTS WILL ONLY BE
ABOUT A TRACE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 331 AM CST TUE JAN 27 2015
OUR NEXT WEATHER MAKER IS PROJECTED TO MOVE THROUGH THE AREA ON
WEDNESDAY AND WEDNESDAY NIGHT. THERE ARE STILL LOTS OF DIFFERENCES
IN THE MODELS...BUT THE CONSENSUS SEEMS TO POINT TO A PAIR OF
SHORTWAVES MOVING THROUGH THE WEST-NORTHWEST UPPER LEVEL FLOW. ONE
IN THE NORTHERN STREAM THAT TRACKS ACROSS THE US/CANADIAN BORDER TO
LAKE SUPERIOR...AND ANOTHER THAT TRACKS FROM COLORADO EAST TO
SOUTHERN ILLINOIS BY THURSDAY MORNING. THE BETTER DYNAMICS ARE
FOCUSED ALONG THESE CORRIDORS...DESPITE THE WAVES BEING PHASED
ENOUGH FOR A SINGLE 850MB LOW MOVING ACROSS THE PLAINS. THE SURFACE
LOW TRACKS FROM WESTERN SOUTH DAKOTA EAST ACROSS IOWA...BUT THE
MODELS HAVE LOTS OF DIFFERENCES HERE...WITH SOME PLACING MORE ENERGY
IN THE NORTHERN STREAM AND PLACING A LOW FARTHER NORTH IN ADDITION
TO THIS MORE SOUTHERLY ONE. EITHER WAY...THE BETTER DYNAMICS STAY
JUST NORTH OF THE AREA AND SKIM THE NORTHERN CWA WITH PRECIPITATION
WEDNESDAY AND WEDNESDAY NIGHT...MAINLY ASSOCIATED WITH THE NORTHERN
STREAM WAVE. STILL LOTS TO SORT OUT WITH THIS SYSTEM...BUT FOR NOW
HAVE KEPT POPS IN THE LIKELY CATEGORY WEDNESDAY NIGHT ACROSS THE
NORTH...WITH LOWER POPS TO THE SOUTH. MID LEVEL TEMPERATURES GET
WARM ONCE AGAIN WITH THIS SYSTEM...AND WE HAVE A VERY REAL THREAT OF
MIXED PRECIPITATION INCLUDING FREEZING RAIN WEDNESDAY AND WEDNESDAY
EVENING BEFORE THE LOW PASSES THE AREA AND STRONG COLD AIR ADVECTION
SWITCHES ALL TO SNOW. SNOWFALL AMOUNTS WITH THIS SYSTEM WILL NOT BE
VERY LARGE...BUT THE MIXED PRECIPITATION MAY CAUSE TRAVEL PROBLEMS.
A STRONG HIGH PRESSURE BUILDS INTO THE AREA FOR THURSDAY NIGHT AND
FRIDAY...BRINGING COLDER TEMPERATURES TO THE REGION. WE MAY BE
LOOKING AT SOME BELOW ZERO TEMPERATURES BY FRIDAY MORNING. ANOTHER
COLD FRONT BRINGS ANOTHER CHANCE OF SNOW TO THE AREA ON
SATURDAY...BEFORE ANOTHER SURGE OF COLD AIR MOVES INTO THE AREA.
SATURDAY NIGHT AND SUNDAY NIGHT WILL BE COLDER YET...WITH
TEMPERATURES IN THE NEGATIVE DOUBLE DIGITS BY MONDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1134 PM CST MON JAN 26 2015
MVFR WITH A FEW IFR CEILINGS COVERED THE NORTHLAND LATE THIS
EVENING...AND ARE EXPECTED TO CONTINUE FOR MOST AREAS INTO AT
LEAST TUESDAY MORNING. OBSERVATIONS AND RADAR INDICATE LITTLE
PRECIP LEFT ACROSS THE AREA AND WE EXPECT THAT THROUGH THE REST OF
THE PERIOD AS WELL.
THE MAIN CHALLENGE CONTINUES TO BE WHEN AND IF THESE LOW CLOUDS
WILL BECOME SCATTERED. THE LATEST NAM AND RAP GUIDANCE CONTINUES
TO PUSH OFF THE CHANGE FROM MVFR/IFR TO VFR. WE WILL DELAY THIS
FOR SEVERAL MORE HOURS WITH THE 06Z TAFS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 32 21 32 22 / 0 10 20 50
INL 32 24 31 14 / 0 10 50 60
BRD 34 25 34 23 / 0 10 10 40
HYR 32 20 33 24 / 0 0 10 50
ASX 33 21 34 25 / 10 0 20 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GSF
LONG TERM...LE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1134 PM CST MON JAN 26 2015
.UPDATE...
ISSUED AT 918 PM CST MON JAN 26 2015
WE DECREASED SNOW/FREEZING DRIZZLE MENTION TONIGHT OVER NORTHERN
AREAS...BUT HELD ONTO OVER PORTIONS OF NORTHERN WISCONSIN FOR A
FEW MORE HOURS. OBSERVATIONS AND RADAR WOULD SUGGEST THE PRECIP IS
SPOTTY.
WE ALSO INCREASED CLOUD COVER TONIGHT INTO TUESDAY MORNING. WE DO
NOT EXPECT MUCH CLEARING OUTSIDE OF SOME POCKETS.
UPDATE ISSUED AT 547 PM CST MON JAN 26 2015
WE MADE SOME ADJUSTMENTS TO POPS EARLY THIS EVENING TO MATCH
CURRENT RADAR TRENDS...MAINLY INCREASING THEM EARLY OVER NORTHERN
WISCONSIN.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 245 PM CST MON JAN 26 2015
PERSISTENT SNOW SHOWERS WITH OCCASIONAL FREEZING DRIZZLE ON THE BACK
EDGE OF THE PRECIPITATION THIS AFTERNOON AND EVENING IS THE MAIN
CONCERN IN THE SHORT TERM. ADDITIONAL SNOW ACCUMULATION WILL BE
MINIMAL TONIGHT...AND ANY DRIZZLE OR FREEZING DRIZZLE TODAY WILL
BECOME ALL SNOW OR FLURRIES BY MIDNIGHT. COULD ALSO SEE PATCHY FOG
AFTER MIDNIGHT TONIGHT.
CLIPPER SYSTEM IS EXITING TO THE SOUTH/SE THIS AFTERNOON WITH A
TRAILING UPPER TROUGH AND AREA OF STEEP LAPSE RATES ALOFT SLIDING
ACROSS WRN ONTARIO AND WEAK HIGH PRESSURE BUILDING IN ON THE BACK
SIDE. A NARROW CORRIDOR OF WARM AIR IN THE MID LEVELS IS PASSING
THROUGH N-CENTRAL MN THIS AFTERNOON AND EARLY EVENING...WHICH IS
ALLOWING FOR VERY LIGHT RAIN/DRIZZLE TO FORM AROUND THE BRAINERD
LAKES AREA...WHILE SNOW SHOWERS CONTINUE THROUGH THE ARROWHEAD AND
OVER N-CENTRAL WI. AREAS IN BETWEEN...ALONG THE HIGHWAY 53 AND
I-35 CORRIDORS COULD SEE A MIX OF SNOW...FREEZING DRIZZLE AND/OR
DRIZZLE THROUGH THIS EVENING. HOWEVER...AS THE NIGHT WEARS ON THE
THREAT FOR PRECIP WILL DECREASE.
THE AIR MASS WILL MODIFY LATE TONIGHT AND TUESDAY MORNING WITH RAPID
DRYING ALOFT...COOLING IN THE NEAR-SFC LAYER...AND WEAK WAA
OCCURRING IN THE MID LEVELS. AS THIS MODIFICATION OCCURS ANY LIQUID
PRECIP WILL BECOME FROZEN...WITH FREEZING DRIZZLE CHANGING OVER TO
FLURRIES. AS THE WARMER AIR ADVECTS IN FROM THE WEST TONIGHT A
WEAK LOW LEVEL INVERSION WILL SET UP AND ALLOW FOR THE POTENTIAL
OF PATCHY FOG ACROSS THE NORTHLAND.
HIGH PRESSURE WILL BUILD IN ACROSS THE UPPER MIDWEST DURING THE DAY
TUESDAY AND KEEP WEATHER CONDITIONS QUIET WITH VERY MILD
TEMPERATURES ONCE AGAIN FROM THE UPPER 20S TO MID 30S. A FEW PEAKS
OF SUN ARE POSSIBLE TUE AFTERNOON...BUT MORE CLOUDS THAN SUN IS THE
MOST LIKELY SCENARIO.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 PM CST MON JAN 26 2015
A COUPLE MORE CLIPPERS WILL MOVE THROUGH THE REGION THIS
WEEK...PROVIDING ADDITIONAL OPPORTUNITIES TO PICK UP LIGHT SNOW. THE
FIRST CLIPPER WILL COME WEDNESDAY...AND THE SECOND ONE LATE THIS
WEEK. THERE IS MUCH LESS CONFIDENCE ON THE TIMING/TRACK/STRENGTH OF
THE SECOND CLIPPER THAN THE FIRST CLIPPER.
A WEAK CLIPPER WILL MOVE OUT OF CANADA INTO THE NORTHERN HIGH PLAINS
LATE TUESDAY...AND MERGE WITH ANOTHER SURFACE LOW PRESSURE CENTER IN
THE NORTHERN/CENTRAL PLAINS TUESDAY NIGHT. THIS COMBINED LOW WILL
DEEPEN AS IT MOVES EAST THROUGH THE CENTRAL PLAINS TOWARDS SOUTHERN
LAKE MICHIGAN WEDNESDAY AND WEDNESDAY NIGHT. THE MODELS INDICATE
THERE WILL BE A WEST TO EAST ORIENTATED BAND OF SNOW THAT WILL
DEVELOP WELL NORTH OF THE LOW WEDNESDAY. THIS BAND WILL PRIMARILY BE
OVER SOUTHERN MANITOBA AND NW ONTARIO...BUT WILL GRADUALLY SAG SOUTH
INTO THE NORTHLAND WEDNESDAY INTO WEDNESDAY EVENING. THE MODELS SHOW
THIS WILL ALSO BE ASSOCIATED WITH A SHORTWAVE AND BROAD UPWARD
MOTION. MOST OF THE SNOW WITH THIS SYSTEM WILL OCCUR LATE WEDNESDAY
AND EARLY THURSDAY. THE NORTHLAND CAN EXPECT A DUSTING TO LESS THAN
AN INCH OF SNOW. THE FAR NORTHERN ARROWHEAD HAS THE BEST CHANCE OF
SEEING MORE THAN ONE INCH OF SNOW. THE ASSOCIATED COLD FRONT WILL
MOVE THROUGH THE REGION WEDNESDAY NIGHT AND EARLY THURSDAY.
COLD NW FLOW WILL DEVELOP THURSDAY IN THE WAKE OF THE COLD FRONT AND
PASSING LOW PRESSURE SYSTEM. THIS WILL BEGIN A COOLING TREND INTO
THE WEEKEND. HIGH PRESSURE WILL MOVE THROUGH THE NORTHERN PLAINS AND
UPPER MIDWEST THURSDAY NIGHT AND FRIDAY...PROVIDING A PERIOD OF
RELATIVELY QUIET BUT COLDER WEATHER.
THE MODELS ARE SHOWING ANOTHER CLIPPER AND COLD FRONT MOVING THROUGH
THE NORTHLAND SOMETIME LATE THIS WEEK. THE GFS HAS A MUCH SLOWER AND
STRONGER CLIPPER THAN THE ECMWF AND GEM. LEANED ON THE ECMWF AND GEM
FOR THE FORECAST...WHICH BRING THE CLIPPER AND ASSOCIATED LIGHT SNOW
THROUGH THE NORTHLAND LATE FRIDAY AND EARLY SATURDAY. THE GFS DOES
NOT BRING THE SNOW THROUGH UNTIL SATURDAY AFTERNOON AND SATURDAY
NIGHT. THE COLD FRONT WILL CONTINUE THE COOLING TREND INTO EARLY
NEXT WEEK. HIGH TEMPERATURES WILL LIKELY BE AT LEAST 10 DEGREES
BELOW NORMAL BY SUNDAY AND MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1134 PM CST MON JAN 26 2015
MVFR WITH A FEW IFR CEILINGS COVERED THE NORTHLAND LATE THIS
EVENING...AND ARE EXPECTED TO CONTINUE FOR MOST AREAS INTO AT
LEAST TUESDAY MORNING. OBSERVATIONS AND RADAR INDICATE LITTLE
PRECIP LEFT ACROSS THE AREA AND WE EXPECT THAT THROUGH THE REST OF
THE PERIOD AS WELL.
THE MAIN CHALLENGE CONTINUES TO BE WHEN AND IF THESE LOW CLOUDS
WILL BECOME SCATTERED. THE LATEST NAM AND RAP GUIDANCE CONTINUES
TO PUSH OFF THE CHANGE FROM MVFR/IFR TO VFR. WE WILL DELAY THIS
FOR SEVERAL MORE HOURS WITH THE 06Z TAFS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 21 32 21 32 / 20 0 10 20
INL 18 32 24 31 / 10 0 10 50
BRD 24 34 25 34 / 10 0 10 10
HYR 19 32 20 33 / 50 0 0 10
ASX 22 33 21 34 / 40 10 0 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...MELDE
SHORT TERM...BJT
LONG TERM...GROCHOCINSKI
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1040 PM CST MON JAN 26 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 343 PM CST MON JAN 26 2015
A SURFACE LOW ANALYZED BY THE RAP NEAR DULUTH THIS AFTERNOON WITH A
STALLED WARM FRONT THROUGH EXTREME WESTERN WI...JUST EAST OF THE MN
BORDER. TEMPERATURES WEST OF THE FRONT HAVE CLIMBED WELL INTO THE
40S ACROSS MOST OF THE REGION WITH DEW POINTS IN THE LOW TO MID 30S.
THIS CAUSES SOME CONCERN FOR FOG DEVELOPMENT OVERNIGHT AS A SURFACE
HIGH/RIDGE AXIS MOVES IN LATE TONIGHT AND WINDS GO NEARLY CALM. THE
TRICKY PART OF THE FORECAST IS HOW FAR WEST THE CLOUD COVER WILL
EXTEND TONIGHT. MODEL GUIDANCE IS QUITE SATURATED AT 925MB BUT CAN
EASILY IMPACTED BY SURFACE MOISTURE. AN INVERSION WILL DEVELOP
AFTER DARK AND COULD LOCK ANY LOW CLOUD COVER IN PLACE. CONFIDENCE
IS LOW IN CLOUD COVER ACROSS WESTERN MN.
IN WEST CENTRAL WISCONSIN...EAST OF THE FRONT...TEMPERATURES HAVE
HELD STEADY IN THE MID 20S WITH -FZDZ AND -SN BEING REPORTED THROUGH
MUCH OF THE DAY. VERY LIGHT AND SCATTER PRECIP WILL CONTINUE MOVING
THROUGH THIS AREA ALONG THE FRONTAL BOUNDARY FOR THE NEXT FEW HOURS.
OTHERWISE...COOLED TEMPS SLIGHTLY FOR TOMORROW ACROSS THE EAST GIVEN
LINGERING CLOUD COVER...AND THE FACT THE SOUTHERLY WINDS ON THE BACK
SIDE OF THE RIDGE DONT ARRIVE UNTIL LATE IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 343 PM CST MON JAN 26 2015
A COUPLE CHANCES FOR LIGHT PRECIPITATION EXIST IN THE EXTENDED
PERIOD OF THE FORECAST...WHILE THE COOLDOWN REMAINS ON TRACK FOR THE
WEEKEND AND INTO EARLY NEXT WEEK.
EARLY AFTERNOON WATERVAPOR IMAGERY TOGETHER WITH GFS 500MB HEIGHTS
AND WINDS SHOWED A BROAD AREA OF NORTHEAST FLOW ACROSS THE CENTRAL
CONUS SANDWICHED BETWEEN THE NEGATIVELY TILTED RIDGE ALONG THE
SPINE OF THE ROCKIES...AND MORE NOTABLY THE NEGATIVE TILTED UPPER
LEVEL TROUGH DRIVING THE POWERFUL NOREASTER OVER THE NEW ENGLAND
AREA. THIS NORTHWEST FLOW PATTERN WILL GENERALLY REMAIN IN PLACE
ACROSS THE UPPER MIDWEST...WITH PERIODIC SHORTWAVES BRINGING
REPEATED CHANCES FOR LIGHT PRECIP.
THE FIRST WILL ARRIVE WEDNESDAY NIGHT...AND THERMAL PROFILES SHOW
THE POTENTIAL FOR A WINTRY MIX OF LIGHT SNOW OR FREEZING DRIZZLE.
NOTE...WEDNEDAYS HIGH TEMPERATURE WILL DEPEND HEAVILY ON CLOUD
COVER...SO DID NOT WARM TEMPS SINCE MID/LOW LEVEL CLOUDS SHOULD KEEP
AFTERNOON HIGHS FROM WARMING OUT OF CONTROL DESPITE THE FAVORABLE
TIMING OF THE WARM AIR ALOFT.
HIGH PRESSURE WILL BUILD IN THURSDAY AND FRIDAY...WITH COLD AIR
ADVECTION LIMITING TEMPS TO NEAR 30 ON THURSDAY...AND 20S ON FRIDAY.
FRIDAY NIGHT ANOTHER SYSTEM WILL MOVE ACROSS THE REGION...BUT
STRENGTH AND TIMING REMAIN UNCERTAIN. THE GFS IS FASTER AND STRONGER
THAN THE ECMWF/GEM...BUT NEITHER SOLUTION PRODUCES SIGNIFICANT
PRECIP...WHICH WILL BE ALL SNOW...ACROSS THE REGION. COLD AIR WILL
FUNNEL IN FOR THE EARLY PART OF NEXT WEEK...AND TO ECHO THE THOUGHTS
OF THE PREVIOUS FORECASTER...IT APPEARS MONDAY WILL HAVE HIGHS IN
THE SINGLE DIGITS...WITH LOWS BELOW ZERO OVERNIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1035 PM CST MON JAN 26 2015
OUTSIDE OF KRWF...WE HAVE HIGH CONFIDENCE IN MVFR CONDITIONS
TONIGHT. SITES THAT ARE CURRENTLY 3000-3200FT...SHOULD SEE SLOW
LOWERING OVER THE NEXT FEW HOURS. VISIBILITY AND PRECIP IS NOT A
CONCERN THROUGH THE MORNING.
KMSP...
WHILE WE EXPECT CEILINGS TO BE BELOW 3000FT FOR THE MORNING
RUSH...WE HAVE MEDIUM TO HIGH CONFIDENCE THEY WILL REMAIN ABOVE
1700FT. SHOULD HAVE LITTLE IN THE WAY OF AVIATION WEATHER IMPACTS
TODAY. THE WINDS SHOULD BE VERY LIGHT AND OUT OF THE N-NE BY THE
MORNING RUSH.
/OUTLOOK FOR KMSP/
WED...VFR. CHC MVFR. WIND SE 10 KT.
THU...CHC MVFR/-SN. WIND NW 10-20 KT.
FRI...VFR. WIND VARIABLE 2-5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...JRB
AVIATION...CLF
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1043 PM MST MON JAN 26 2015
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS SHOULD BE MAINTAINED THROUGH THE NEXT 24 HOURS AT
ALL TERMINAL SITES. A VERY ISOLD SHRA OR HIGH MT SHSN WILL BE
POSSIBLE FROM THE CONTINENTAL DIVIDE TO THE AZ BORDER THROUGH 00Z
WEDNESDAY. VERY BRIEF MT OBSCURATIONS POSSIBLE ALONG THE DIVIDE.
CHANCES NOW SO SLIM FOR A SHOWER IN KGUP WILL NOT INCLUDE VCSH IN
TAF.
&&
.PREV DISCUSSION...901 PM MST MON JAN 26 2015...
.UPDATE...
UPPER LEVEL LOW ACROSS THE PACIFIC HAS RETROGRADED SO FAR WEST
THAT PRECIPITATION CHANCES FOR NM CONTINUE TO DWINDLE DESPITE ONE
LOBE OF ENERGY KICKING OUT ACROSS SOCAL. HRRR AGREES AND PRODUCES
LITTLE QPF ACROSS WESTERN NM AND NEW GUIDANCE FOR THE NAM SUGGEST
NONE. THUS HAVE RATCHETED DOWN POPS FOR TONIGHT...AND EVEN
THEN...THEY STILL MAY BE TOO HIGH. AMOUNTS LOOK TO BE LESS THAN A
TENTH OF AN INCH IF ANYONE DOES RECEIVE PRECIP. WITH THE SYSTEM SO
FAR WEST...THE EFFECTS SHOULD BE MINIMALIZED GOING INTO TOMORROW
AS WELL SO HAVE LOWERED POPS ONCE AGAIN FOR TUESDAY. HAVE ALSO
LOWERED OR REMOVED POPS FOR WEDNESDAY AND WEDNESDAY NIGHT AS WELL
AS ANY REMAINING EFFECTS FROM THIS STORM SYSTEM SHOULD LARGELY
REMAIN NORTH OF THE NM/CO BORDER AS IT ROUNDS THE RIDGE.
OTHERWISE...MINOR TWEAKS TO TONIGHTS TEMPS AND SKY COVER. UPDATES
ALREADY OUT.
34
&&
.PREV DISCUSSION...241 PM MST MON JAN 26 2015...
.SYNOPSIS...
A LARGE BUT SLOW MOVING STORM DRIFTING OUT OF THE EASTERN PACIFIC
COASTAL WATERS OF BAJA CALIFORNIA INTO THE GREAT BASIN THROUGH
TUESDAY WILL INTRODUCE SOME SHOWERS IN WESTERN NEW MEXICO THROUGH
TUESDAY. A MIDWEEK BREAK FROM WEATHER WILL COME TO AN END LATE
THURSDAY...AS THE NEXT TROPICAL PACIFIC OCEAN STORM DRIFTS INTO
THE DESERT SOUTHWEST. SLOW MOTION WILL PRODUCE LONGER PERIODS OF
RAIN AND HIGH COUNTRY SNOW THROUGH MUCH OF FRIDAY AND INTO THE
FOLLOWING WEEKEND. COLDER AIR SAGGING SOUTHWARD WILL MOVE SHOWER
COVERAGE TO SOUTHERN NEW MEXICO AS THE WEEKEND WINDS UP...WITH
SOUTHERN CLOUDS CONTRASTING WITH NORTHERN CLEARING AS THE WORK
WEEK GETS UNDERWAY IN THE FIRST DAYS OF FEBRUARY.
&&
.DISCUSSION...
CURRENTLY...RIDGE ALOFT EXTENDING FROM SOUTH TEXAS ACROSS NEW
MEXICO TO THE INLAND PACIFIC NORTHWEST RIGHT NOW...AS LARGE
PACIFIC STORM SYSTEM SITS OFF THE SOUTHERN CALIFORNIA COAST WELL
WEST OF NEW MEXICO...AND SPEEDY POLAR JET STREAM FROM WESTERN CANADA TO
THE GULF OF MEXICO COAST PROVIDING THE FEATURE TO THE EAST OF NEW
MEXICO. BROAD SURFACE DOME OF HIGH PRESSURE OVER NEW MEXICO WILL
REMAIN IN PLACE FOR RIGHT NOW.
MODELS...IN GOOD AGREEMENT THROUGH NEXT WEEKEND...AND A START ON
MONDAY. DIFFERENCES EMERGING LATE MONDAY ONWARD...AS EUROPEAN
COLLEAGUES AT ECMWF MOVE THEIR SYSTEM EASTWARD WITH
AUTHORITY...WHILE DOMESTIC GFS COLLEAGUES ARE MUCH SLOWER WITH
EASTWARD DRIFT OF SYSTEM ACROSS THE SOUTHWESTERN U.S. THROUGH
MIDWEEK OF THE FOLLOWING WEEK. GOOD START CONVERTS PACIFIC SYSTEM
CORE INTO A WAVE AND SHEARS THE WAVE ACROSS SOUTHERN CALIFORNIA
TONIGHT...AND ON INTO THE CENTRAL ROCKIES BY TUESDAY NIGHT. FLOW
OVER NEW MEXICO WILL SIMPLY VEER FROM SOUTHERLY TO WESTERLY BY
MIDWEEK...AS QUICK DISTURBANCE MOVING ACROSS THE CENTRAL ROCKIES
MIGHT TAG THE NORTHERN TIER OF NEW MEXICO ON WEDNESDAY NIGHT.
UPSTREAM...NEXT TROPICAL PACIFIC SYSTEM WILL DEEPEN OFF SOUTHERN
CALIFORNIA AND WESTERN BAJA CALIFORNIA...AND THIS TROUGH WILL
DRIFT AGONIZINGLY SLOWLY TO SOUTHERN CALIFORNIA THURSDAY
NIGHT...TO THE COLORADO VALLEY IN WESTERN ARIZONA FRIDAY...AND
THEN A WOBBLE INTO NORTHERN SONORA ON SATURDAY. STORM WILL PICK UP
STRONG POSITIVE TILT ON SUNDAY...WITH CORE REMAINING OVER
NORTHWESTERN MEXICO...AND THIS WILL CLOSE UP INTO A LOW OVER THE
SOUTHERN PORTIONS OF BAJA CALIFORNIA NEAR CABO SAN LUCAS AND LA
PAZ TO KICK OFF THE WORK WEEK. DIFFERENCES EMERGING INTO
TUESDAY...AS EUROPEAN SYSTEM WILL PICK UP EASTBOUND SPEED...REACH
TEXAS BY TUESDAY AND DROP STRONGER NORTHWEST FLOW INTO NEW MEXICO
BY WEDNESDAY. DOMESTIC GFS...ON THE OTHER HAND...WILL KEEP SYSTEM
POSITIVELY TILTED BUT MUCH SLOWER...WITH CORE OVER EASTERN NEW
MEXICO ON WEDNESDAY AND MUCH WEAKER NORTHWEST FLOW ALOFT OVER THE
REMAINDER OF THE STATE. DIFFERENCES FROM MONDAY NIGHT ONWARD ARE
SOMEWHAT MODEST...SO CAN SIMPLY SPLIT THE DIFFERENCE FOR NOW AND
KEEP AN EYE ON FUTURE RUNS FOR ANY NEEDED IMPROVEMENT ON RUN TO
RUN CONTINUITY FOR ONE VERSION OR THE OTHER.
OVERNIGHT...MILDER OVERNIGHT YET AGAIN...AS CLOUD COVER AND SOME
SHOWER COVERAGE WORKS NORTH ACROSS CATRON COUNTY AND ON TOWARD
INTERSTATE 40 FROM THE ARIZONA LINE TO THE CONTINENTAL DIVIDE.
MOST SPOTS WILL PICK UP ISOLATED TO SCATTERED RAIN SHOWERS...WITH
SOME OVERNIGHT CHANGE OVER TO SNOW OVER THE CHUSKA MOUNTAINS AND
SUMMITS SLOPES OF THE CONTINENTAL DIVIDE BY EARLY TUESDAY
MORNING. SNOW ACCUMULATION NOT EXPECTED TO BE MUCH IN THESE HIGHER
SPOTS. RIDGE AXIS WILL DRIFT EAST OVERNIGHT...AND END UP LYING FROM
TEXAS INTO THE NORTHERN ROCKIES ON THE EAST SIDE OF NEW MEXICO BY
TUESDAY MORNING. OVERNIGHT WINDS WILL RUN ON THE LIGHT SIDE.
FOR TUESDAY...FLOW OVER NEW MEXICO GOING FROM ZERO UNDER THE RIDGE
TO SOMEWHAT STAGNANT SOUTHWEST FLOW BY TUESDAY AFTERNOON...AS
NORTH BOUND TROUGH CLIPS THE FOUR CORNERS AND SHEARS OFF INTO
WESTERN COLORADO. SURFACE TROUGH FROM WEST KANSAS TO THE TEXAS
PANHANDLE WILL RETURN WEST TO SOUTHWEST FLOW ACROSS THE SURFACES
IN THE EAST...WITH SOME BREEZES GOING THROUGH THE SANGRE DE CRISTO
MOUNTAINS IN THE NORTH...AND ALONG INTERSTATE 40 IN THE EASTERN
SLOPES AND ADJACENT PLAINS OF THE CENTRAL MOUNTAIN CHAIN THROUGH
TUESDAY AFTERNOON. LAST OF THE WESTERN ISOLATED SHOWER COVERAGE
WITH HIGH COUNTRY SNOWFALL WILL MIGRATE TO THE NORTHERN TIER
TUESDAY NIGHT AS SURFACE TEMPERATURES REMAIN 8 TO 15 DEGREES ABOVE
LATE JANUARY NORMALS. SNOW ACCUMULATION WILL RUN ON THE LOW
SIDE...AND FOCUS ON THE SAN JUAN AND NORTHERN SANGRE DE CRISTO
SUMMITS...AND SOME CHANCE FOR A LITTLE SNOW OVER THE JEMEZ SUMMITS
BEFORE STORMS MOVE NORTH TUESDAY EVENING.
FOR WEDNESDAY...FLOW ALOFT PICKING UP SPEED AND VEERING FROM
SOUTHWEST TO WEST...AS QUICK SHORTWAVE MAKES QUICK TRIP EASTWARD
ACROSS SOUTHERN COLORADO THROUGH WEDNESDAY AFTERNOON. SURFACE LOW
DEEPENING OVER THE MISSOURI RIVER VALLEY AS HIGH PRESSURE SETS UP
OVER THE GREAT BASIN TO THE WEST WILL SUPPORT SOME NORTHWEST
BREEZES ACROSS NEW MEXICO...WITH BREEZY SPEEDS OVER THE SANGRE DE
CRISTO AND CENTRAL MOUNTAIN CHAIN SUMMITS...AND SETTING UP EASTERN
SLOPES AND ADJACENT PLAINS NORTHWEST BREEZES OVER THE INTERSTATE
40 CORRIDOR IN THE EAST. LAST OF THE ISOLATE SHOWER COVERAGE WILL
FLICKER OVER THE NORTHERN TIER NEAR THE COLORADO LINE THROUGH
WEDNESDAY NIGHT. MIDWEEK DAYTIME TEMPERATURES RUNNING
STEADY...WITH 8 TO 15 DEGREE WARM DEPARTURES ON TAP...WARMEST IN
THE EAST.
FOR THURSDAY...COLD FRONT OUT OF THE CENTRAL PLAINS STATES WILL
INVADE EASTERN NEW MEXICO DURING THE DAY...AND EXPAND RAPIDLY WEST
AND SOUTH TO THE CONTINENTAL DIVIDE BY LATE THURSDAY AFTERNOON
INTO THURSDAY NIGHT. ACTION WILL BRING TEMPERATURES OUT OF THE
WARMTH AND INTO CLIMATOLOGICAL CLOSENESS TO NORMAL FOR LATE
JANUARY...A FEW DEGREES COOL IN THE EAST. DAYTIME SHOWERS OVER THE
NORTHERN MOUNTAINS...AND BUILDING THE NEXT ROUND INTO THE SOUTHWEST
AND SOUTH CENTRAL MOUNTAINS...WILL BECOME BROAD AND WIDESPREAD
RAIN AND SNOW THURSDAY NIGHT AS THE SOUTHWEST BOUND COLD FRONT
COLLIDES RAPIDLY WITH EASTBOUND TROPICAL STORM SYSTEM WORKING INTO
NEW MEXICO. BREEZY EAST TO SOUTHEAST WINDS WILL SET UP OVER THE
SOUTHERN HALF OF THE STATE NEAR THE FRONT AND UNDER THE BEST
DYNAMICS OVERHEAD...AND THIS COULD SET UP SOME EASTERLY BREEZES
THROUGH THE CENTRAL MOUNTAIN CHAIN AND OUT OVER THE RIO GRANDE
VALLEY THROUGH THURSDAY AFTERNOON WITH THESE BREEZES CONTINUING
THROUGH THURSDAY NIGHT.
OUTLOOK...FRIDAY THROUGH THE WEEKEND...BIG COOL DOWN WILL PUSH
TEMPERATURES INTO DOUBLE DIGITS BELOW NORMAL BY SUNDAY...A TAD
LESS EXTREME IN THE WEST. STORM CORE OVER NEW MEXICO FRIDAY WILL
GRADUALLY WEAKEN COLD FRONT ON SATURDAY AS STORM REMAINS IN
PLACE AND CONTINUES TO KEEP WEATHER UNSETTLED...AND THEN AS NEXT
RAPIDLY SINKING COLD FRONT REINVIGORATES OVER EXTREME SOUTHERN NEW
MEXICO...STORM FOCUS WILL SHIFT TO THE SOUTHERN HALF OF THE STATE
THROUGH SUNDAY. FRIDAY AND SATURDAY WILL REMAIN BREEZY OVER THE
SOUTH WITH CONTINUING EAST TO SOUTHEAST WINDS...WITH WIND SPEEDS
DROPPING OFF ON SUNDAY AS DIRECTIONS SHIFT TO MORE NORTHERLY.
SHY
&&
.FIRE WEATHER...
NO CRITICAL FIRE WX CONDITIONS EXPECTED FOR AT LEAST THE NEXT WEEK.
ALSO LOOKING AT AN INCREASING POTENTIAL FOR A WIDESPREAD WETTING
PRECIP EVENT BETWEEN THU NIGHT AND SAT NIGHT ACROSS THE ENTIRE FCST
AREA.
OVERALL QUIET PATTERN TO CONTINUE INTO THU MORN...WITH FEW
EXCEPTIONS. POOR VENT RATES WILL STILL REMAIN THE CASE INTO TUE
AS WINDS ALOFT TO BE FAIRLY LIGHT AND SFC PRESSURE GRADIENT PRETTY
WEAK. TEMPS TO CONTINUE WELL ABOVE SEASONAL AVERAGES INTO WED
AREA WIDE. AN UPPER LOW WEST OF THE NORTHERN BAJA REGION WILL HEAD
INTO CALIFORNIA LATE TONIGHT AND THE GREAT BASIN TUE...BUT WEAKEN
SOME AS IT DOES SO. WHILE MOISTURE IS COMING INTO NM CURRENTLY AND
WILL CONTINUE TO DO SO INTO TUE...IT WILL WILL BE MORE IN THE MID
AND UPPER LEVELS AND LESS SO DOWN LOW. FCST MODELS CONTINUE TO TREND
LOWER WITH AMT OF PRECIP TO BE SQUEEZED OUT TONIGHT THROUGH WED
ACROSS THE WEST AND NORTH WITH LITTLE INDICATION OF ANY AMTS INTO
THE WETTING CATEGORY OF A TENTH OF AN INCH OR MORE DURING THIS
PERIOD. EXPECTED MAINLY ISOLATED LIGHT RAIN SHOWERS AND HIGHER MTN
SNOW SHOWERS MAINLY NEAR AND WEST OF THE DIVIDE.
WINDS SFC AND ALOFT TO INCREASE SIGNIFICANTLY TUE NIGHT AND WED
MOSTLY ACROSS THE NORTHERN MTNS AND EAST FROM THE CENTRAL MTN
CHAIN...BUT MINIMUM RH VALUES TO BE TOO HIGH FOR ANY CRITICAL FIRE
WX CONDITIONS TO DEVELOP...THOUGH SOME WIND GUSTS BETWEEN 35 AND 45
MPH ARE POSSIBLE THESE AREAS. SOME MODEST VENTILATION RATE
IMPROVEMENTS EXPECTED...MAINLY FROM NW AND SANDIA/MANZANO MTS OVER
THE CENTRAL HIGHLANDS AND FAR NORTHEAST. MOST OTHER LOCATIONS WILL
CONTINUE TO SEE POOR TO MARGINALLY FAIR RATES WED. THEREAFTER A
BACKDOOR COLD FRONT WILL PUSH INTO NM...BRINGING SOME COOLING AND A
PERIOD OF MOISTENING EAST TO WEST LOW LEVEL WINDS. GUSTY EASTERLY
WINDS INTO THE RIO GRANDE VALLEY APPEAR LIKELY TO DEVELOP BY LATE
WED NIGHT OR THU MORN AND PERSIST THROUGH THU NIGHT AND PERHAPS FRI.
ANOTHER SURGE OF COOLER AIR AT THE SURFACE COULD OCCUR BY FRI NIGHT
OR SAT. NEITHER OF THESE SURGES SHOULD BE TERRIBLY COLD...BUT WILL
DROP TEMPS SLIGHTLY TO MODERATELY BELOW NORMAL. AS MENTIONED BRIEFLY
AT START OF THIS DISCUSSION WE ARE LOOKING AT INCREASING POTENTIAL
FOR WIDESPREAD WETTING PRECIP OVER MUCH OF NORTHERN AND CENTRAL NM
STARTING THU NIGHT AND CONTINUING THROUGH SAT BEFORE TAPERING OFF.
SNOW LEVELS MAY DROP SOME AS THIS EVENT GOES ON...BUT STILL LOOKS
LIKE THEY WILL BE RANGING FROM ABOUT 3500 TO ABOUT 5500 FEET EAST
AND GENERALLY BETWEEN 6000 AND A LITTLE OVER 7500 WEST. VENT RATES
IMPROVE THU...DUE TO STRONGER TRANSPORT WINDS...BUT WORSEN AGAIN
FRIDAY...AND AGAIN PERHAPS IMPROVING MAINLY EAST SAT.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1256 AM EST TUE JAN 27 2015
.SYNOPSIS...
EARLY THIS MORNING, THE CLIPPER THAT BROUGHT SNOW SHOWERS TO THE
REGION WILL BECOME A POWERFUL NOR EASTER. A PERIOD OF HEAVY SNOW
IS POSSIBLE OVER THE POCONOS TO CATSKILLS TODAY INTO THE EVENING.
A COLD WINTRY WEATHER PATTERN WILL PERSIST THROUGH THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
10 PM UPDATE...
LATEST HRRR IS KEEPING THE HEAVY SNOW BAND OUT OF PIKE/SULLIVAN
THROUGH THE OVERNIGHT HOURS, SO CONFIDENCE IN INTENSE SNOW IN THE
WARNING AREA OVERNIGHT IS DROPPING. SNOWFALL AMOUNTS FROM EARLIER
TURNED OUT TO BE HIGHER THAN EXPECTED DUE TO A HIGH SNOW TO H20
RATIO. MANY LOCATIONS HAVE REPORTED 3 TO 5 INCHES OF SNOW ALREADY,
SO WE MAY STILL REACH WARNING CRITERIA.
NO CHANGES TO FLAGS AT THIS TIME. WE HAVE LOWERED AMOUNTS SLIGHTLY
FOR THE OVERNIGHT HOURS.
425 PM UPDATE...
ISSUED A LAST SECOND WINTER WEATHER ADVISORY FOR PORTIONS OF
CENTRAL SO TIER AND FINGER LAKES. WE ARE RECEIVING REPORTS OF 3 TO
4 INCHES OF SNOW FROM TRAINED SPOTTERS IN THIS AREA, AND HRRR
HOLDS ACTIVITY OVER THE NEW ADVISORY AREA THROUGH THE EVENING. NEW
PROJECTIONS ARE FOR 3 TO 6 INCHES OVER THIS REGION.
330 PM EST UPDATE...
THE CALM BEFORE THE STORM...
LIGHT SNOW SHOWERS HAVE ADVANCED NORTHWARD THIS AFTERNOON AND NOW
HAVE REACHED PRETTY MUCH THE WHOLE CWA. THESE SHOWERS ARE EXPECTED
TO CONTINUE TO LIFT NORTHWARD THIS EVENING AND ADDITIONAL
ACCUMULATIONS OF 1 TO 3 INCHES OF SNOW ARE POSSIBLE... ESPECIALLY
OVER THE FINGER LAKE REGION.
TEMPS HAVE RISEN QUITE A BIT FROM THIS MORNING AND CURRENTLY RANGE
IN THE MID TEENS TO LOW 20S. TEMPS MAY INCREASE A COUPLE MORE
DEGREES THIS AFTERNOON THEN WILL SLOWLY DECREASE AFTER SUNSET.
THIS EVENING THE CLIPPER THAT HAVE BROUGHT THE CWA SNOW THIS
AFTERNOON WILL TRANSITION OVER TO A POWERFUL NOR`EASTER AND CREATE
COPIOUS AMOUNTS OF SNOWFALL FOR MUCH OF THE NORTHEAST. THIS
NOR`EASTER WILL BE DISCUSSED IN THE FOLLOWING SECTION.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/...
330 PM EST UPDATE...
AS MENTIONED BEFORE THE CLIPPER WILL TRANSFORM INTO A POWERFUL
NOR`EASTER AND CREATE AN ALMOST STAND STILL FOR MUCH OF THE NEW
ENGLAND COAST. SNOW FROM THIS SYSTEM IS STILL EXPECTED TO START
AFTER 06Z TONIGHT AND MAY PREVAIL THROUGH THE LATE EVENING HOURS
ON TUESDAY. WE CONTINUE TO REMAIN ON THE FAR OUTER EDGE OF THIS
SYSTEM. WITH THAT BEING SAID... THERE ARE STILL SOME UNCERTAINTIES
WITH HOW MUCH SNOWFALL WILL FALL IN OUR CWA FROM THIS SYSTEM.
CONFIDENCE IS DECREASING THAT WE WILL REACH WARNING CRITERIA FOR
SULLIVAN AND PIKE COUNTY. ATTM IT APPEARS THAT THE GREATEST
MOISTURE AXIS WILL REMAIN WELL TO OUR EAST. ALSO... WITH EACH NEW
GUIDANCE RUN HINTING AT THAT EDGE SHIFTING EVER SO SLIGHTLY
EAST... WE MAY REACH ADVISORY AND NOT WARNING CRITERIA FOR THOSE
TWO COUNTIES. IT IS STILL TOO FAR OUT IN THE EVOLUTION OF THIS
STORM TO KNOW WHERE EXACTLY THE CUTOFF OF WARNING CRITERIA WILL
BE... THUS KEPT PREVIOUS WARNING/ADVISORY LOCATIONS THE SAME.
STORM TOTAL SNOWFALL ACCUMULATIONS WERE MODIFIED JUST SLIGHTLY
FROM THE PREVIOUS FORECAST. THE HIGHEST EXPECTED SNOWFALL
ACCUMULATIONS OVER THE CWA ARE STILL EXPECTED TO BE IN THE WESTERN
CATSKILLS AND THE POCONO MOUNTAIN REGION. ATTM... KEPT TEN TO
FOURTEEN INCHES TOTAL OVER THESE REGIONS. WE WILL CLOSELY MONITOR
THE OVERALL EVOLUTION OF THIS STORM AND UPDATE AS NECESSARY.
WINDS WILL BECOME GUSTY DURING THE DAY TOMORROW AND CREATE BLOWING
AND DRIFTING SNOW. WINDS ARE EXPECTED TO RANGE FROM 10 TO 20 MPH
WITH GUSTS UP TO 30. THIS WILL CREATE HAZARDOUS DRIVING
CONDITIONS.
TEMPS AFTER THIS SYSTEM PULLS AWAY WILL BE VERY COLD FALLING INTO
THE SINGLE DIGITS OR SLIGHTLY BELOW ZERO.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
220 PM UPDATE...
HIGH PRESSURE BUILDS IN QUICKLY BHND DEPARTING NOR`EASTER WITH CLDS
CLRNG DRG THE MRNG FM WEST TO EAST. H8 TEMPS WARM TO NR -10C
YIELDING HIGHS IN THE L/M 20S. S/WV RIDGING WORKS IN ALOFT WED NGT
WITH MOCLR SKIES THRU MOST OF THE OVRNGT BFR CLOUDING UP FM THE WEST
BY 12Z. DRY WX EXPECTED TO HOLD THRU THUR MRNG.
WARM ADVECTION WL OVRSPRD WRN ZONES THURSDAY MORNING BRINGING A LO
CHC OF LGT SNOW TO FINGER LKS AREA. UPR TROF AND ASSOC FRONTAL
SYSTEM SWINGS THRU THURSDAY NGT AND WITH ALL MODELS INDICATING THIS
SOLN HV OPTED TO GO LKLY POPS FOR SNOW BTWN 00Z AND 12Z FRIDAY. NW
FLOW WL CONTINUE BHND SYSTEM LEADING TO ANOTHER CHC FOR LK EFFECT
SNOW SHOWERS THRU FRI NGT UNTIL NEXT HIGH BUILDS IN.
BASICALLY FOLLOWED WPC GUIDANCE THRU THE END OF THE LONG TERM WITH
HIPRES RESULTING IN DRY WX THRU THE FIRST HALF OF THE WEEKEND. NEXT
CHC FOR SNOW SHOWERS APPEAR TO MV IN ON SUNDAY.
MODELS DIFFER SIGNIFICANTLY LATE IN THE LONG TERM WITH CLD CANADIAN
AIR FILTERING IN AS 12Z GFS HAS LOPRES OVR TOP OF CWA AS OPPOSED
TO EC INDICATING NRLY FLOW WITH HIPRES. THUS HV GONE WITH WPC
NUMBERS FOR LOWS NEXT MON MRNG WITH LOW TEMPS BLO ZERO.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
1230 AM UPDATE...
MAINLY VFR CONDITIONS. A NORTH TO SOUTH BAND OF SNOW OVER ELM
GIVING THEM MVFR VSBYS AND AT TIMES IFR VSBYS EARLY. THIS BAND
WILL TAPER OFF TO FLURRIES AND CONDITIONS WILL RISE TO VFR.
THE MAIN SHIELD OF SNOW OVER SE NY IS EXPECTED TO GET TO KRME WITH
WEAK LAKE ENHANCEMENT OFF LAKE ONTARIO. POSSIBLE IFR VSBYS 19 TO
23Z BUT MAINLY MVFR CIG/VSBY. ALSO WITH THE NW FLOW SYR ITH BGM
SHOULD FALL TO MVFR IN SNOW SHOWERS.
ELM AVP AFTER 12Z VFR WITH ONLY FLURRIES.
N TO NE WINDS AT 4 TO 8 KTS EARLY THIS MORNING SHIFT TO NW TO N AT
10 WITH GUSTS TO 20 LATE MORNING INTO EARLY EVE. SLIGHTLY WEAKER
WINDS LATE EVENING OUT OF THE NW.
OUTLOOK...
TUE NGT-WED...LINGERING LAKE EFFECT -SHSN AND MVFR CIGS/VSBYS
POSSIBLE MAINLY NY TERMINALS INTO WED MORNING...OTHERWISE MAINLY
VFR.
THU AND FRI...RESTRICTIONS FROM -SN.
SAT...BECOMING VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR PAZ048.
WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR PAZ040-
072.
NY...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR NYZ062.
WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR NYZ046-
057.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR NYZ015-
016-022>024.
&&
$$
SYNOPSIS...KAH
NEAR TERM...DJP/KAH
SHORT TERM...KAH
LONG TERM...PVF
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
241 AM EST TUE JAN 27 2015
.SYNOPSIS...STRONG LOW PRESSURE OFF NEW ENGLAND THIS MORNING WILL
LIFT NORTHEAST AWAY FROM OUR AREA TODAY. HIGH PRESSURE WILL BUILD IN
FROM THE NORTHWEST THIS AFTERNOON THROUGH EARLY THURSDAY. ANOTHER
CLIPPER LOW PRESSURE SYSTEM WILL SWING BY JUST TO OUR NORTH LATE
THURSDAY THROUGH THURSDAY NIGHT... THEN HIGH PRESSURE WILL AGAIN
BUILD INTO OUR AREA FROM THE NORTHWEST ON FRIDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
AS OF 240 AM TUESDAY...
TODAY AND TONIGHT: FRONTAL SYSTEM IS CURRENTLY MOVING THROUGH THE
AREA AS LOW PRESSURE CONTINUES TO DEEPEN ACROSS THE DELMARVA. THE
CWA IS CURRENTLY SPLIT BETWEEN DRIER AIR TO THE WEST OF ROUTE 1 AND
MORE MOISTURE TO THE EAST. A BAND OF PRECIPITATION HAS SET UP ALONG
WHAT APPEARS TO BE THE FRONTAL BOUNDARY AND HAS BROUGHT SOME
SCATTERED REPORTS OF A RAIN/SNOW MIX FROM PERSON COUNTY DOWN THROUGH
WAKE COUNTY WITH MOSTLY RAIN OR DRIZZLE SOUTH OF THERE. THIS BAND
WILL MOVE GRADUALLY EASTWARD THROUGH THE EARLY MORNING HOURS TOWARDS
TEH I-95 CORRIDOR AND THE EASTERN TIER OF COUNTIES. SCATTERED
REPORTS OF LIGHT SNOW OR RAIN WILL CONTINUE THROUGH THE MORNING
BEFORE MOST LOCALES DRY OUT. THE THREAT FOR SNOW SHOULD END AFTER
12Z AS RAP FORECAST SOUNDINGS INDICATE SIGNIFICANT DRYING IN THE
SNOW GROWTH ZONE. NO ACCUMULATION IS EXPECTED OR ANY IMPACTS FROM
THE SNOW ASIDE FROM A POTENTIAL DUSTING ON ELEVATED SURFACES AT BEST
AS SOIL TEMPERATURES ARE STILL NEAR 40 DEGREES.
THIS SETUP HAS ALSO CAUSED A SPLIT IN CLOUD COVER WITH AREAS UNDER
AND EAST OF THE PRECIPITATION BAND EXPERIENCING MAINLY MVFR CEILINGS
WITH VFR CONDITIONS BACK TO THE WEST. A FEW WIND GUSTS STILL OUT
THERE UP TO 20 KTS OR SO OUT OF THE NORTHWEST. GUSTS MAY DIE OFF
TOWARDS SUNRISE BUT WILL PICK UP AGAIN LATER THIS AFTERNOON.
TEMPERATURES THIS AFTERNOON IN THE LOW TO MID 40S NE TO SW AS CLOUDS
LINGER LONGER AND COLD AIR ADVECTION IS MORE PRONOUNCED IN THE
NORTHEAST. EXPECT DRYING TO CONTINUE INTO TONIGHT WITH CLEARING
SKIES BUT WINDS REMAINING 5-10 KTS SO NOT EXACTLY GREAT FOR
RADIATIONAL COOLING BUT TEMPS WILL STILL MANAGE TO DROP INTO THE
MIDDLE 20S WITH THE CHANGE IN AIRMASS.
WEDNESDAY AND WEDNESDAY NIGHT: A DRY DAY EXPECTED FOR WEDNESDAY AS
CENTRAL NC IS SANDWICHED BETWEEN THE EXITING BLIZZARD TO THE
NORTHEAST AND INCOMING HIGH PRESSURE TO THE NORTHWEST. SURFACE
PRESSURE GRADIENT WILL RELAX A LITTLE BUT STILL A GOOD COLD AIR
ADVECTION REGIME BOTH AT THE SURFACE AND ALOFT ON THE BACK SIDE OF
THE UPPER LEVEL TROUGH. THIS WILL KEEP TEMPS DOWN IN THE LOW TO MID
40S...ABOUT 10 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. WINDS 5-
10 KTS OUT OF THE NORTH VEERING TO NORTHEASTERLY LATER IN THE DAY.
CLOUDS WILL GRADUALLY INCREASE IN THE NORTHWEST ON WEDNESDAY NIGHT
AS THE NEXT LOW PRESSURE SYSTEM MOVES INTO THE OHIO VALLEY. THIS
WILL HELP TO KEEP LOW TEMPERATURES UP IN THE TRIAD. GENERALLY MID
20S BUT POSSIBLY SOME LOWER 20S IN OUR EASTERN NORMALLY COLD ZONES.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 200 AM TUESDAY...
THU/THU NIGHT: THE GREAT LAKES SHORTWAVE TROUGH WILL TRACK ESE THEN
EASTWARD ACROSS THE NORTHEAST/MIDATLANTIC STATES... TRACKING THROUGH
THE BASE OF THE POLAR LOW OVER HUDSON BAY... WHILE ITS CORRESPONDING
SURFACE LOW CROSSES THE OH VALLEY AND MIDATLANTIC COAST. AFTER A
CHILLY MORNING WITH THE SURFACE RIDGE OVERHEAD... INCREASING
SOUTHERLY LOW LEVEL FLOW AS THE HIGH SHIFTS SSE WILL ALLOW FOR A
MODEST RECOVERY IN THICKNESSES... BUT STILL BELOW NORMAL... AND THE
TEMP RISE WILL BE HINDERED BY THICKENING AND LOWERING CLOUDS WITH
APPROACHING WEAK MID LEVEL DPVA AND LOW LEVEL FRONTAL ZONE. BUT
MODELS STILL SHOW PW VALUES JUST BARELY REACHING ABOVE NORMAL... AND
GFS/NAM BUFR FORECAST SOUNDINGS SHOW A DRY SUBCLOUD LAYER BELOW 850
MB THROUGH THU. MODEL QPF IS ALSO SCANT WITH THE GFS/NAM/SREF MEAN
STAYING DRY OVER CENTRAL NC THROUGH THU NIGHT. AFTER 00Z THE COLUMN
STARTS TO DRY OUT ALOFT BEHIND THE 700 MB TROUGH... AND JUST AHEAD
OF THE SURFACE FRONT WHICH IS EXPECTED TO SWEEP EAST THROUGH CENTRAL
NC AFTER MIDNIGHT. WILL TRIM BACK EXISTING SLIGHT CHANCE POPS A
BIT... FOCUSING THEM LATE THU AFTERNOON UNTIL SHORTLY AFTER
MIDNIGHT... HOWEVER AM RELUCTANT TO REMOVE THEM ENTIRELY AS THE
ECMWF CONTINUES TO GENERATE LIGHT PRECIP LATE THU AFTERNOON AND THU
EVENING. EXPECT HIGHS THU IN THE MID 40S TO AROUND 50. LOWS THU
NIGHT 32-38.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 200 AM TUESDAY...
FRI-SAT: THE MID LEVEL TROUGH AXIS WILL BE SWINGING TO OUR EAST FRI
MORNING WITH THE SURFACE COLD FRONT PUSHING OFF THE NC COAST. NW LOW
LEVEL FLOW WILL BRING IN COOLER AIR AS HIGH PRESSURE INITIALLY
CENTERED OVER NRN MINN DRIFTS SOUTHEAST... BUILDING INTO AND OVER
THE MIDATLANTIC THROUGH VA/ERN NC THROUGH SAT. SHOULD SEE MOSTLY
CLEAR SKIES FRI/FRI NIGHT... FOLLOWED BY INCREASING HIGH THIN CLOUDS
SAT AS WE START TO SEE INITIAL ENERGY EJECTING FROM THE DESERT SW
LOW TRACK EASTWARD WITHIN CONFLUENT NW MID LEVEL FLOW. WITH FALLING
THICKNESSES FRI... EXPECT BELOW-NORMAL HIGHS IN THE MID 40S TO LOWER
50S. LOWS FRI NIGHT IN THE MID 20S... THEN WITH SUCH A CHILLY START
AND THE CANADIAN-SOURCE AIR MASS BUILDING IN YIELDING THICKNESSES AT
LEAST 30 M BELOW NORMAL... HIGHS SAT SHOULD ONLY BE IN THE 40-45
RANGE.
SAT NGT-MON: A LOT OF UNCERTAINTY IN THE DETAILS PERSISTS THIS
MORNING... HOWEVER IT`S LOOKING MORE LIKELY THAT WE`RE ENTERING INTO
A PERIOD OF MORE ACTIVE WEATHER DOMINATED BY SOUTHERN STREAM ENERGY
BUT WITH POTENTIAL INJECTIONS OF COOLER AIR FROM THE NORTHERN
STREAM. A NRN STREAM WAVE DROPPING SOUTHEAST FROM MT THROUGH THE
CENTRAL PLAINS WILL MERGE WITH SOUTHERN STREAM ENERGY EMANATING FROM
THE LOW OVER NRN MEX SAT NIGHT/SUN... BRINGING MID LEVEL DPVA INTO
NC SUN/SUN NIGHT. THE SHIFTING OF THE SURFACE HIGH ESE OFF THE COAST
WILL ALLOW A MOIST RETURN FLOW OFF THE GULF INTO THE GULF/MIDSOUTH
AND SOUTHEAST STATES... AS SURFACE LOW PRESSURE DEVELOPS ALONG THE
BAROCLINIC ZONE NEAR THE NW GULF COAST AND TRACKS NORTHEAST TOWARD
NC. THE GFS/ECMWF BRING PRECIP INTO WRN NC BY MIDDAY SUN... THEN
SPREAD IT EASTWARD THROUGH CENTRAL NC SUN NIGHT INTO EARLY MON
MORNING. BOTH THE GFS/ECMWF SHOW A MILLER TYPE-B CYCLOGENESIS
PATTERN BUT WITH VARIED LOW PLACEMENT... WITH THE ECMWF DEPICTING A
FURTHER-SOUTH TRIPLE POINT LOW TRACK VERSUS THE GFS. THE LATEST RUNS
SHOWS SUFFICIENTLY WARM LOW- AND MID-LEVEL THICKNESSES TO SUPPORT AN
ALL-RAIN EVENT... BUT GIVEN THIS PATTERN... WILL NEED TO WATCH MODEL
TRENDS CAREFULLY IN THE COMING DAYS. WITH OTHERWISE GOOD MODEL
AGREEMENT ON TIMING AND THE MID-LEVEL PATTERN... WILL BUMP UP
POPS... FOCUSING THE HIGHER CHANCES SUN AFTERNOON THROUGH SUN
NIGHT... TAPERING DOWN WEST-TO-EAST MON MORNING AS THE DAMPENING MID
LEVEL SHORTWAVE TROUGH SHIFTS EAST OVER THE MIDATLANTIC/ NORTHEAST
WITH SURFACE FRONTAL PASSAGE THROUGH NC. EXPECT IMPROVING WEATHER
LATE MON WITH ANOTHER CANADIAN HIGH CENTERED OVER THE MIDWEST
BUILDING INTO OUR AREA. EXPECT BELOW NORMAL TEMPS THROUGH SUN
NIGHT... WITH MORE UNCERTAINTY FOR HIGHS ON MON AS MUCH WILL DEPEND
ON WHETHER OR NOT WE GET INTO THE WARM SECTOR BEFORE FRONTAL
PASSAGE. WILL KEEP TEMPS BELOW NORMAL FOR NOW BUT IF MODEL WARMING
TRENDS HOLD... MAY NEED TO BUMP UP MON HIGHS QUITE A BIT IN LATER
FORECASTS. -GIH
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 100 AM TUESDAY...
24 HOUR TAF PERIOD: CONDITIONS AT THIS HOUR ARE GENERALLY SPLIT
BETWEEN VFR IN THE WEST WHERE IT IS CONSIDERABLY DRIER AND MVFR IN
THE EAST WHERE MORE MOISTURE IS PRESENT IN THE LOWER LEVELS. MVFR
CONDITIONS ARE DUE TO LOWER CEILINGS WITH VISIBILITIES EVERYWHERE
COMING IN AT 10 SM. THERE CONTINUE TO BE A FEW WIND GUSTS OUT THERE
UP TO 20 KTS...PARTICULARLY IN THE NORTHEAST WHICH MAKES SINCE AS
THE PRESSURE GRADIENT THERE INCREASES CLOSER TO THE LOW OFFSHORE.
WINDS ARE GENERALLY OUT OF THE NORTHWEST AND WILL STAY THAT WAY
THROUGH THE TAF PERIOD. GUSTS ARE EXPECTED TO RELAX AFTER 9Z. AS
DRIER AIR CONTINUES TO WORK IN FROM THE WEST CONDITIONS WILL IMPROVE
BACK TO VFR AND REMAIN THERE THROUGH THE PERIOD. GUSTS OF 15-20 KTS
WILL BE PREVALENT AGAIN LATER IN THE AFTERNOON. THERE IS A CHANCE
FOR A LINGERING RAIN SHOWER OR EVEN A FEW SNOW FLURRIES AS WE
CONTINUE THROUGH THE MORNING WITH THE MOST LIKELY LOCATION BEING THE
NORTHEAST. ONE OTHER NOTE...PILOT REPORTS HAVE BEEN COMING IN AROUND
KRDU AND POINTS NORTH FOR LIGHT TO MODERATE ICING FROM 4-12 KFT.
LONG TERM: THE NEXT THREAT TO AVIATION CONDITIONS WILL BE THURSDAY
NIGHT INTO FRIDAY MORNING AS A FRONTAL SYSTEM CROSSES THE AREA AND
THEN ANOTHER SYSTEM SUNDAY INTO MONDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...ELLIS
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
317 AM CST TUE JAN 27 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 315 AM CST TUE JAN 27 2015
FORECAST CHALLENGE CONCERNS TEMPERATURES AND MIDWEEK SNOW CHANCES.
MODELS IN REASONABLE AGREEMENT AND WILL USE MODEL BLEND.
MAIN CHALLENGE TODAY WILL BE TEMPERATURES WHICH WILL HINGE ON WHAT
CURRENT CLOUD COVER DOES DURING THE DAY. CURRENT STRATUS CLOUD
SHIELD EXTENDS FROM VALLEY EASTWARD. MODELS CURRENTLY NOT HANDLING
CLOUD TRENDS WELL AT ALL AND HAVE DIFFERENT SOLUTIONS ON WHAT CLOUDS
WILL DO. HIGH RESOLUTION (HRRR) WAY TOO FAR WEST WITH LOWER CIGS
WHILE MOST OTHER MODELS TOO QUICK IN PUSHING LOW LEVEL MOIST
EASTWARD. GFS AND TO A DEGREE THE NAM WANT TO CLEAR OUT THE VALLEY
AND DEVELOP LOWER CIGS WEST OF THE VALLEY THIS AFTERNOON. AS LOW
LEVEL FLOW STRENGTHENS FROM THE S-SW DURING THE AFTERNOON ALONG
WITH INCREASING WARM ADVECTION WESTERN EDGE SHOULD ERODE BUT MAY
BE TOO LATE FOR SOLAR TO AID IN WARMING. WITH UNCERTAINTY DID NOT
DIFFER TOO MUCH ON MAXIMUM TEMPERATURES.
REGION REMAINS IN WARM SECTOR OVERNIGHT FOR ANOTHER MILD NIGHT.
COLDER AIR BEGINS TO SAG INTO THE FA WEDNESDAY. DURING THE DAY
MODELS SLOWER IN BRINGING PCPN INTO THE FA AND KEEP MOST
APPRECIABLE QPF NORTH OF THE BORDER. WITH MODELS TRENDING FOR
LIGHTER AMOUNTS OF PCPN AND DELAY IN BRINGING MOISTURE SOUTH OF
INL BORDER DELAYED/TRIMMED POPS DURING THE AM AND HELD WITH CHANCE
POPS DURING THE DAY AS ECMWF AND NAM NEARLY DRY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 315 AM CST TUE JAN 27 2015
MORE FAVORABLE UPPER SUPPORT MOVES INTO THE REGION LATER WEDNESDAY
SO MAINTAINED HIGHER POPS AND DECREASED POPS FROM WEST TO EAST
AFTER MIDNIGHT AS WAVE PUSHES EAST.
TEMPERATURES TREND COLDER TO FINISH OFF THE WORK WEEK BUT STILL ON THE
WARM SIDE OF SEASONAL AVERAGES.
UPPER LEVEL PATTERN CONTINUES WITH NW FLOW ALOFT...BEFORE AN UPPER
LEVEL TROF SAGS OVER THE AREA BY THE WEEKEND. SFC HIGH PRESSURE OVER
THE REGION WILL SHIFT SE ON FRIDAY AHEAD OF A DEVELOPING CLIPPER
SYSTEM. THIS SYSTEM WILL BRING ANOTHER CHANCE FOR LIGHT
PRECIPITATION...AND USHER IN COOLER TEMPERATURES FOR THE AREA
THROUGH THE REST OF THE PERIOD. OTHERWISE...NO MAJOR SYSTEMS
EXPECTED AND THE OVERALL WEATHER PATTERN WILL REMAIN QUIET.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1130 PM CST MON JAN 26 2015
FAR AND DVL COULD SEE SOME BR OR FG OVERNIGHT TONIGHT WHILE THE
WINDS ARE CALM. WILL SEE SOME IMPROVEMENT IN THE MORNING AS SE FLOW
PICKS UP. FOR NORTHWEST AND W CNTRL MN...CLOUDY SKIES SHOULD
INHIBIT VSBYS FROM FALLING TOO DRASTICALLY BUT CIGS HAVE DROPPED
INTO IFR RANGE AND 06Z TAFS WILL REFLECT THIS. THE HRRR DOES KEEP
THE IFR CONDS IN FOR MUCH OF MUCH OF THE DAY TOMORROW...HOWEVER
WITH INCREASING SE FLOW THINK WE WILL SEE IMPROVED CONDS BY LATE MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...VOELKER
LONG TERM...HOPKINS/VOELKER
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
258 AM CST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 257 AM CST TUE JAN 27 2015
ONLY AREA OF STRATUS VERY EARLY THIS MORNING IS SITUATED THROUGH
PORTIONS OF SOUTHWESTERN MINNESOTA INTO THE IOWA GREAT LAKES
AREA...WITH SOME PATCHY FOG LOCATED WITHIN THIS NARROW BAND. BOTH
THE RAP AND SREF ARE HANDLING THESE LOW CLOUDS/REDUCED VISIBILITY
WELL...AND HAVE IT DISSIPATING BY 15Z. OTHERWISE...THE REMAINDER OF
THE CWA REMAINS FOG FREE THIS MORNING SO REMOVED MOST OF THE FOG
FROM THE FORECAST. HIGH PRESSURE SITUATED ACROSS THE REGION THIS
MORNING WILL PUSH OFF TO THE EAST THROUGH THE DAY...AND AS IT DOES
SO THE LOW LEVEL FLOW WILL BECOME SOUTHEASTERLY. THIS AND A
STRENGTHENING INVERSION WILL INHIBIT MIXING TODAY...ESPECIALLY IN
THE EAST...AND IN RESPONSE HIGH TEMPERATURES WILL GENERALLY BE
COOLER THAN YESTERDAY. STILL VERY MILD FOR THIS TIME OF YEAR
HOWEVER...TOPPING OUT IN THE LOWER 40S THROUGH SOUTHWESTERN
MINNESOTA INTO THE EASTERN PORTIONS OF OUR IOWA ZONES...TO 50S
THROUGH THE JAMES RIVER VALLEY THROUGH THE LOWER MISSOURI RIVER
CORRIDOR.
A SURFACE TROUGH BEGINS TO APPROACH FROM THE WEST TONIGHT...AND IT
WILL BE A MILDER NIGHT WITH INCREASING WARM AIR ADVECTION OUT AHEAD
OF THE SYSTEM. WITH THAT...LOOKING AT LOWS GENERALLY LOWER TO MID
30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 257 AM CST TUE JAN 27 2015
WEDNESDAY STILL TO BE THE FINAL VERY MILD DAY AS LOW PRESSURE PASSES
AND COOLER AIR BEGINS TO DRAIN SOUTHWARD. MODELS SIMILAR TO
YESTERDAY SO NO REAL CHANGES. STILL MAINTAIN A SMALL CHANCE FOR
LIGHT SNOW IN THE NORTH AS A WAVE PASSES BY BUT A BIT MOISTURE
STARVED SO NOT ANTICIPATING MUCH OF ANYTHING.
BECOMING A BIT WINDY LATE WEDNESDAY AFTERNOON AND NIGHT AS COLD AIR
ADVECTION AND A STRONG PRESSURE GRADIENT WORK TO MIX DOWN SOME
STRONG WINDS ALOFT. LIKELY SEE SOME WIND GUSTS OF 35 MPH OR SO
WEDNESDAY NIGHT. WITH SOME CLOUD COVER AND WIND TEMPERATURES SHOULD
STAY FAIRLY MILD FOR THIS TIME OF YEAR WITH THURSDAY MORNING LOWS
FROM THE MID 20S TO LOWER 30S.
THURSDAY STILL A BIT BREEZY AND DEFINITELY COLDER. THE LOWER LEVEL
THERMAL FIELD HAS COME IN A BIT COLDER THIS TIME AROUND WHICH IS
ALSO FAIRLY WELL AGREED UPON SO WENT AHEAD AND LOWERED HIGHS A
COUPLE OF DEGREES. HIGHS MAINLY UPPER 20S TO MID 30S.
IN THE OUTER PERIODS (FRIDAY THROUGH MONDAY)...THE COLDER PATTERN
SETTLES IN AND REMAINS IN PLACE. MODELS ALL IN PRETTY GOOD AGREEMENT
THIS TIME AROUND SO WILL KEEP TEMPERATURES ON THE COLDER SIDE OF
GUIDANCE. FRIDAY IS THE LAST OF THE MILD DAYS AS SOUTHERLY FLOW
KEEPS 925MB TEMPERATURES CLOSER TO ZERO. SATURDAY LIKELY POSING THE
POTENTIAL FOR THE BIGGEST ERROR IN FORECASTING AS THE ARCTIC
BOUNDARY IS PROGGED TO MOVE THROUGH. A LITTLE FASTER AND HIGHS WILL
BE IN THE 20S...A LITTLE SLOWER AND HIGH WOULD BE IN THE 40S SO
UPPER 20S IN THE NORTH AND MID 30S IN THE SOUTH SEEMS LIKE A GOOD
HEDGE TOWARDS THIS FAIRLY SHARP THERMAL GRADIENT. WILL ALSO HAVE A
CHANCE FOR LIGHT SNOW ON SATURDAY AND SATURDAY NIGHT AS THIS COLD
AIR SURGES SOUTH. SUNDAY AND MONDAY WELL INTO THE COLD AIR SO JUST
LOOKING AT HIGHS IN THE TEENS TO LOWER 20S AND LOWS IN THE SINGLE
DIGITS TO LOWER TEENS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1028 PM CST MON JAN 26 2015
VFR EXPECTED THROUGH 28/06Z...EXCEPT FOR AREAS OF FOG 27/09Z-
15Z. FOG WILL PRODUCE AREAS OF VISIBILITIES 3-5SM WITH LOCAL
VISIBILITIES BELOW 3SM.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JM
LONG TERM...08
AVIATION...
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
315 AM CST TUE JAN 27 2015
.DISCUSSION...
CURRENTLY...SOME LIGHT SNOW INDICATED OVER CENTRAL AREAS OF KY.
LATEST MODEL RUNS SUPPORT THE SOUTHWARD MOVING IMPULSE.
HOWEVER...BEST REGION OF PVA THROUGH THE MORNING HOURS WILL BE
MAINLY EAST OF THE MID STATE...NORTHERN AREAS OF THE PLATEAU MAY
BE ON THE WESTERN FRINGE. THUS...WITH HRRR IN AGREEMENT WITH
TRENDING TOWARD LESS IN THE WAY OF SNOWFALL...WILL OPT TO TREND
DOWNWARD THE SNOW THREAT. HALF INCH ACCUMULATIONS WILL BE POSSIBLE
FOR THE NORTHERN PLATEAU ONLY FOR THIS MORNING...GENERALLY A TRACE TO A
QUARTER INCH ELSEWHERE ACROSS THE PLAT. AREAS JUST WEST OF THE
PLATEAU COULD SEE A FEW FLURRIES. OTHERWISE...CLOUDS WILL HANG ON
THROUGH TODAY...BUT CLEARING LINE NOT TOO FAR OFF TO THE
SOUTHWEST.
PARTIAL CLEARING WILL BEGIN TONIGHT AS HIGH PRESSURE SETTLES IN JUST
TO OUR NORTH. COLD TEMPS FOR TONIGHT WITH LOWS RANGING FROM NEAR 20
PLATEAU...AND MOSTLY LOWER TO MID 20S ELSEWHERE.
SUNSHINE WILL BE THE RULE FOR WEDNESDAY. A WEAK RIDGE AXIS WILL
STRETCH ACROSS THE MID STATE SO WE SHOULD SEE TEMPS WARM UP CLOSE TO
50 DEGREES FOR MOST AREAS.
A CLIPPER SYSTEM WILL THEN BE ON APPROACH AND THE ASSOCIATED
FRONTAL BOUNDARY WILL MOVE THROUGH ON THURSDAY. THIS WILL
TRANSLATE TO A CHANCE OF SHOWERS LATE WED NT INTO THURSDAY. THE
SFC LOW WILL PASS A GOOD DISTANCE TO THE NORTH OF TN. TEMPS WILL
THEREFORE REACH INTO THE LOWER TO MID 50S DURING THE DAY.
IN THE EXT FCST...COLDER AND MORE SEASONAL AIR WILL WORK IN BEHIND
THE CLIPPER SYSTEM. THEN...THE GULF STORM...THAT WE HAVE BEEN
LOOKING AT FOR SEVERAL DAYS NOW...WILL BEGIN TO GET ITS ACT
TOGETHER. FOR SEVERAL RUNS NOW...THE EURO MODEL WAS COLDER AND WAS
SUPPORTING A POTENTIAL SNOW EVENT WHILE THE GFS WAS A WARMER RAIN
SCENARIO. WELL...THE EURO HAS BACKED OFF AND IS NOW SHOWING MORE OF
A N-S TROUGH INVERSION AS OPPOSED TO THE COLDER W-E AXIS. THIS NOW
MATCHES UP WITH THE WARMER GFS SOLUTION. THUS...WILL TREND TOWARD
MORE OF A RAIN EVENT FOR SAT NT INTO SUNDAY. AT ANY RATE...LOOKS
LIKE ABOUT 1/2 TO PERHAPS 3/4 INCH RAINFALL AMOUNTS.
COLD AIR TO WORK INTO THE AREA BY SUNDAY AS THE MOISTURE IS PULLING
OUT. WILL INCLUDE A SLIGHT CHANCE OF SNOW.
MON AND TUES OF NEXT WEEK LOOK COLD...BUT NOTHING TOO BAD AS UPPER
FLOW IS MORE WESTERLY. SPLIT FLOW IS INDICATED BUT THE SOUTHERN JET
WILL BE WELL SOUTH OF THE AREA. JUST DRY WITH TEMPS 5 DEGREES OR SO
BELOW NORMAL.
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 45 25 50 38 / 10 0 0 20
CLARKSVILLE 43 25 49 40 / 10 0 0 20
CROSSVILLE 37 20 42 35 / 30 0 0 10
COLUMBIA 48 27 52 39 / 10 0 0 20
LAWRENCEBURG 50 28 52 39 / 10 0 0 10
WAVERLY 45 26 51 40 / 10 0 0 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1122 PM CST MON JAN 26 2015
.UPDATE...
ISSUED AT 856 PM CST MON JAN 26 2015
CONDITIONS HAVE GREATLY IMPROVED OVER THE PAST HOUR. THIS IS DUE
TO A COMBINATION OF DIFFERENT REASONS:
1. PRECIPITATION HAS BEEN ON THE WANE. THERE WAS A NICELY EVIDENT
VORT MAX ON RADAR THAT CAME THROUGH THE FORECAST AREA BETWEEN
23-01Z. SUBSIDENCE IN THE WAKE OF THIS VORT HAS HELPED TO SQUASH A
LOT OF THE DEVELOPMENT PREVIOUS MODEL RUNS WERE SUGGESTING ALONG
THE INVERTED SURFACE TROUGH. ADDITIONALLY...SURFACE CONVERGENCE
ALONG THE TROUGH IS NOT THAT STRONG AS WINDS HAVE DIMINISHED SOME
WEST OF THE MISSISSIPPI RIVER. LASTLY...ALL THE PREVIOUS SNOW
THAT WAS UP IN NORTHWEST WISCONSIN HAS NOW PROGRESSED TO THE
SOUTHEAST INTO EASTERN WI AND OUT OF THE FORECAST AREA.
2. ROADS HAVE BEEN IMPROVING RESULTING FROM TREATMENTS WORKING ON
THEM. THE DIMINISHING OF PRECIPITATION HAS ONLY AIDED THIS MORE.
DUE TO THE IMPROVING CONDITIONS...HAVE CANCELLED THE WINTER
WEATHER ADVISORY EARLY. STILL CANNOT RULE OUT SOME PATCHY LIGHT
FREEZING DRIZZLE OR LIGHT SNOW WITH THAT INVERTED TROUGH
AROUND...BUT NOT ENOUGH COVERAGE EXISTS TO WARRANT THE ADVISORY
OUT ANYMORE.
UPDATE ISSUED AT 459 PM CST MON JAN 26 2015
HAVE EXPANDED THE ADVISORY INTO FAR SOUTHWEST WISCONSIN WHERE
NUMEROUS REPORTS OF BAD ROADS HAVE BEEN RECEIVED...ESPECIALLY
SECONDARY ROADS.
ALSO HAVE EXTENDED THE ADVISORY UNTIL MIDNIGHT. A WARM FRONT SITS
ALONG THE MISSISSIPPI RIVER...WHICH APPEARS TO BE STUCK NOW THAT
ITS PARALLEL WITH THE UPPER LEVEL FLOW. ADDITIONALLY...A SURFACE
LOW OVER NORTHWEST WI WILL RIDE DOWN ALONG THIS FRONT...SETTING UP
AN INVERTED TROUGH IN ITS WAKE. LOW LEVEL VERTICAL MOTION SHOULD
PERSIST ALONG AND EAST OF THIS BOUNDARY...AND WITH TEMPERATURES IN
THIS ZONE BELOW FREEZING...WE SHOULD SEE A CONTINUATION OF
FREEZING DRIZZLE THROUGH THE EVENING. THIS IS SHOWN NICELY IN THE
LATEST HRRR RUNS...RAP...26.12Z REGIONAL CANADIAN AND 26.18Z NAM.
ANOTHER CONCERN IS THE MASS OF SNOW MARCHING SOUTH OUT OF
NORTHWEST WISCONSIN...WHICH SHOULD MARCH DOWN THROUGH CENTRAL WI
OVER THE NEXT FEW HOURS. THE COMBINATION OF THIS SNOW AND
FREEZING DRIZZLE WARRANTS A CONTINUATION OF THE ADVISORY. LUCKILY
IMPACTS SHOULD CONTINUE TO DECREASE AS ROADS CONTINUE TO BE
TREATED...THOUGH THE LOSS OF DAYTIME HEATING WILL ALLOW UNTREATED ROADS
TO COOL AND MAKE THINGS WORSE.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 331 PM CST MON JAN 26 2015
MAIN FORECAST PROBLEM WILL BE LINGERING FREEZING DRIZZLE
CHANCES THROUGH THIS EVENING.
SURFACE MAP THIS AFTERNOON HAS SURFACE LOW OVER THE ARROWHEAD WITH A
WARM FRONT EXTENDING ACROSS EASTERN MN/IA. TEMPERATURES RANGED FROM
THE MIDDLE 30S TO MIDDLE 40S BEHIND THE FRONT ACROSS SOUTHEAST
MN/NORTHEAST IA...TO THE LOWER TO MIDDLE 20S EAST OF THE MISSISSIPPI
RIVER/AHEAD OF THE FRONT. LOWER LEVEL ISENTROPIC LIFT ACROSS THIS
FRONT WAS PRODUCING AREAS OF FREEZING DRIZZLE EAST OF THE
MISSISSIPPI WITH REPORTS OF SOME SLIPPERY STRETCHES ON ROADWAYS VIA
WI 511 AND FROM LOCAL ROAD CREW.
LOOK FOR THE SURFACE LOW TO MOVE SOUTHEAST FROM THE ARROWHEAD OF MN
THIS AFTERNOON INTO NORTHWEST IL BY EARLY THIS EVENING. MAIN LIFT
AHEAD OF THIS LOW ...WHICH IS PRESENTLY CAUSING THE FREEZING DRIZZLE
WILL THEREFORE BE IN A WANING PHASE WITH ITS PASSAGE. HOWEVER...RAP
BUFKIT SOUNDING SHOWS SOME LINGERING LIFT ACROSS CENTRAL WI THROUGH
LATER THIS EVENING AS THE MID-LEVEL/SURFACE INVERTED TROUGH HANGS
UP. WILL THEREFORE CONTINUE TO CARRY FREEZING DRIZZLE MENTION INTO
THIS EVENING. THERE MAY BE SOME LIGHT SNOW AS WELL WITH POCKETS OF
FEEDER/SEEDER ICE. MAY HAVE TO EXTEND CURRENT ADVISORY A LITTLE
LONGER INTO THIS EVENING TO COVER FOR THIS. WILL KEEP A CLOSE EYE ON
IT.
HIGH PRESSURE BUILDS OVER THE AREA LATER TONIGHT THROUGH TUESDAY FOR
QUIET WEATHER. LOOKS LIKE IT WILL REMAIN MOSTLY CLOUDY THOUGH DESPITE
HIGH BUILDING IN DUE TO MOISTURE BEING TRAPPED UNDER THE SUBSIDENCE
INVERSION. WITH PARTIAL SUNSHINE LATE IN THE MORNING THROUGH THE
AFTERNOON...PLAN ON HIGHS REBOUNDING INTO THE 30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 331 PM CST MON JAN 26 2015
UNSEASONABLY MILD CONDITIONS EXPECTED FOR WEDNESDAY AHEAD OF
APPROACHING LOW PRESSURE ACROSS THE PLAINS. DESPITE AN INCREASE IN
STRATUS CLOUD...LOOK FOR HIGHS WELL INTO THE 30S WITH POSSIBLY A FEW
LOWER 40 READINGS ACROSS PARTS OF NORTHEAST IA INTO FAR SOUTHWEST WI.
A WINTRY MIX LOOKS TO IMPACT THE AREA WEDNESDAY NIGHT INTO THURSDAY
MORNING AS THE LOW OVER THE PLAINS MOVES TOWARD THE GREAT LAKES
REGION. MODEL SOUNDINGS NOT SHOWING A LOT OF ICE IN CLOUD FOR SNOW
PRODUCTION...SO LOOKS LIKE MORE OF A FREEZING RAIN/DRIZZLE POTENTIAL
AS A RESULT. WILL CONTINUE TO MONITOR THIS.
LATEST GFS/ECMWF SHOW ANOTHER STORM SYSTEM MOVING OUT OF THE PLAINS
TOWARD THE UPPER MISSISSIPPI RIVER REGION SATURDAY AFTERNOON INTO
SUNDAY FOR SNOW CHANCES.
OTHERWISE...LOOKS LIKE A SIGNIFICANT COOL DOWN THROUGH THE
WEEKEND/EARLY NEXT WEEK AS PATTERN SHIFTS TO NORTHWEST FLOW ALOFT.
HIGHS ON SATURDAY EXPECTED TO BE IN THE 20S...COOLING INTO THE
SINGLE DIGITS/TEENS BY MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1122 PM CST MON JAN 26 2015
STRATUS CONTINUES TO PLAGUE THE TAF SITES THIS EVENING...MOSTLY
OF THE MVFR VARIETY BUT OCCASIONALLY VFR. WITH THE FLOW TURNING
NORTHERLY AND PLENTY OF STRATUS THAT EXTENDS INTO NORTHERN
ONTARIO...BELIEVE THE STRATUS WILL STICK AROUND THROUGH MUCH OF
TUESDAY. ADDITIONALLY...WITH TEMPERATURES ABOVE THE CLOUD
WARMING...ITS POSSIBLE THAT THE CLOUD WILL GET PUSHED LOWER
CAUSING CEILINGS TO LOWER. FOR NOW STILL KEPT THE CEILINGS IN THE
MVFR RANGE...BUT BEARS WATCHING. AS WINDS SWING AROUND TO THE
SOUTH TO SOUTHWEST TUESDAY EVENING...FOLLOWING THE PASSAGE OF A
SURFACE RIDGE OF HIGH PRESSURE...ANTICIPATING CLEARING OF THE LOW
CLOUDS CURRENTLY IN WESTERN IOWA TO SURGE THROUGH THE TAF SITES.
ONLY LAST ITEM OF NOTE ARE SOME SNOW SHOWERS MOVING THROUGH LSE.
THESE SHOULD BE DONE BY 07Z AS THE TROUGH FORCING THEM WEAKENS.
ANY VISIBILITY REDUCTION SHOULD BE LIMITED TO MVFR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1021 PM CST MON JAN 26 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 545 PM CST MON JAN 26 2015
QUICK CHECK WITH WOOD COUNTY INDICATED ROADS JUST SNOW COVERED...
WITH NO MAJOR TRAVEL PROBLEMS REPORTED. WILL ALLOW THE ADVISORY
TO EXPIRE AT 600 PM.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 245 PM CST MON JAN 26 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAKENING
LOW PRESSURE SYSTEM MOVING SSE AS IT APPROACHES FAR NORTHWEST
WISCONSIN. AHEAD OF THE LOW...MODEST WARM ADVECTION AND MID-LEVEL
FGEN ARE CONTRIBUTING TO A BAND OF SNOW...BUT THE BEST RETURNS
APPEAR TO BE EXITING CENTRAL WISCONSIN EARLY THIS AFTERNOON. THE
LATEST DATA SHOW THAT THE MID-LEVEL FGEN WILL CONTINUE TO WEAKEN AS
THE BEST WARM ADVECTION PULLS OUT...SO SHOULD SEE ONLY VERY LIGHT
SNOW OR FLURRIES FOR A PERIOD UNTIL BETTER RETURNS OVER WESTERN LAKE
SUPERIOR ARRIVE. STILL SEEING OBSERVATIONS AT MARSHFIELD AND
MEDFORD OF FREEZING DRIZZLE OR UNKNOWN PRECIP...SO NO PLANS TO
CHANGE THE ADVISORY. SOME POSSIBILITY THAT IT COULD GET EXTENDED
INTO THE EVENING...BUT NO INDICATIONS OF FREEZING DRIZZLE ELSEWHERE
THOUGH. SNOWFALL ACCUMS AND IMPACTS REMAIN THE MAIN FORECAST
CONCERNS.
TONIGHT...CLIPPER LOW PRESSURE WILL CONTINUE TO WEAKEN AS IT TRACKS
ACROSS FAR SW WISCONSIN EARLY THIS EVENING AND INTO WESTERN
ILLINOIS. ANOTHER AREA OF LIGHT SNOW ASSOCIATED WITH WARM ADVECTION
WILL MOVE ACROSS NORTH-CENTRAL AND EASTERN WISCONSIN THAT WILL
PROLONG THE LIGHT SNOW FOR MUCH OF THE EVENING. THE SNOW WILL
LIKELY DIMINISH OVER CENTRAL WISCONSIN BY MID TO LATE EVENING...BUT
SATURATION WILL REMAIN DEEP ENOUGH FOR PATCHY FREEZING DRIZZLE...SO
LEFT THAT POSSIBILITY IN THE FORECAST ON THE WESTERN EDGE OF THE
PRECIP. THE HIGHEST ACCUMULATIONS WILL BE OVER EASTERN WISCONSIN
WHERE A HALF INCH OR INCH WILL LIKELY FALL. LIGHT ONSHORE FLOW FROM
SE WINDS MAY LOCALLY BOOST TOTALS HIGHER OVER THE DOOR PENINSULA
FROM LAKE ENHANCEMENT. MOST GUIDANCE SUPPORTS LIGHT PRECIP
DIMINISHING LATE TONIGHT ACROSS THE EAST...THOUGH FLURRIES COULD
CONTINUE IN THE EAST DUE TO THE LIGHT ONSHORE FLOW. LOWS MAINLY
BETWEEN 19-24 DEGREES.
TUESDAY...BECAUSE WEAK LOW LEVEL CONVERGENCE WILL BE
CONTINUING...THINK OVERCAST CONDITIONS WILL PERSIST THROUGH MUCH OF
THE MORNING HOURS. AS ARCTIC HIGH PRESSURE TRIES TO REBUILD INTO
THE REGION DURING THE AFTERNOON...SHOULD SEE THE LOW OVERCAST ERODE
FROM THE WEST AND ALSO THE EAST WHICH WILL LEAD TO INCREASING
SUNSHINE. HIGHS WILL RANGE FROM THE UPPER 20S TO LOWER 30S.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 245 PM CST MON JAN 26 2015
A COUPLE OF WEAK UPPER TROUGHS WILL APPROACH FROM THE WEST
WEDNESDAY NIGHT AND BRING SOME LIGHT SNOW TO THE REGION. NOT
MUCH MOISTURE AVAILABLE BUT THERE IS PRETTY GOOD LOW LEVEL WARM
ADVECTION AND CONVERGENCE IN NORTHEAST WISCONSIN. THINK WE WILL
GET 1 TO 3 INCHES WITH THE GREATEST AMOUNTS OVER DOOR MARINETTE
AND FLORENCE AND FOREST COUNTIES.
LAKE EFFECT SNOW SHOWERS POSSIBLE IN NORTHCENTRAL WISCONSIN
WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT BUT ACCUMULATIONS SHOULD
BE LIGHT. DRY AND COLDER FRIDAY AND SATURDAY. AN ARCTIC COLD
FRONT WILL APPROACH THE AREA SATURDAY NIGHT AND SUNDAY AND SHOULD
BE ABLE TO PRODUCE SOME LIGHT SNOW AS IT MOVES ACROSS THE AREA.
MONDAY SHOULD BE QUITE COLD WITH SUBZERO HIGHS POSSIBLE IN
NORTHERN WISCONSIN.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1019 PM CST MON JAN 26 2015
THE SYSTEM PRODUCING THE SNOW WILL CONT TO SLOWLY SHIFT OFF TO
THE SE TNGT...BUT MVFR/IFR CIGS WILL LINGER IN THE MOIST CYCLONIC
FLOW REMAINING BEHIND THE DEPARTING SYSTEM. CIGS IN CENTRAL WI MAY
EVEN DROP INTO THE LIFR CATEGORY FOR A WHILE OVERNIGHT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
222 AM PST TUE JAN 27 2015
.SYNOPSIS...A STORM SYSTEM OFF THE SOUTHERN CALIFORNIA COAST WILL
MOVE NORTH BRINGING A CHANCE OF SHOWERS TO MUCH OF THE CENTRAL
CALIFORNIA INTERIOR THROUGH THE AFTERNOON HOURS. DRY WEATHER WILL
RETURN BY WEDNESDAY...HOWEVER...ANOTHER STORM WILL BRING A RENEWED
CHANCE OF SHOWERS TO MAINLY THE MOUNTAINS AND DESERT WEDNESDAY INTO
FRIDAY.
&&
.DISCUSSION...AN UPPER LOW OFF THE SOUTHERN CALIFORNIA COASTLINE
CONTINUES TO BRING LIGHT TO MODERATE RAIN SHOWERS TO MUCH OF THE
REGION. THE HEAVIEST RAIN WAS OBSERVED IN KERN COUNTY IN THE PAST
6 HOURS...WHERE DESERT AND MOUNTAIN LOCATIONS PICKED UP BETWEEN A
QUARTER OF AN INCH TO NEARLY TWO-THIRDS OF AN INCH.
OTHERWISE...MANY VALLEY LOCATIONS FROM TULARE AND KINGS COUNTY
SOUTHWARD PICKED UP A FEW HUNDREDTHS OF AN INCH TO A TENTH OF AN
INCH. THE HIGH RES ARW...NMM...AND HRRR ALL INDICATE THAT SHOWERS
WILL CONTINUE TO SPREAD NORTHWARD...HOWEVER VERY LITTLE
ACCUMULATION IS EXPECTED. THIS ACTIVITY IS FORECAST TO CONTINUE
INTO THE EARLY AFTERNOON HOURS...WITH RAIN AND SNOW SHOWERS
CONTINUING OVER THE SIERRA NEVADA INTO THE EVENING HOURS...AS THE
UPPER LOW SHIFTS QUICKLY NORTHEAST OUT OF THE REGION.
SNOW LEVELS WITH THIS STORM WILL REMAIN AROUND 7,500 FEET WITH A
FEW INCHES POSSIBLE OVER SIERRA CREST.
HIGH PRESSURE WILL BRIEFLY BUILD OVER CALIFORNIA ON WEDNESDAY
BEFORE A WEAK UPPER TROUGH IMPACTS THE REGION THURSDAY INTO
FRIDAY. THE UPPER TROUGH WILL BECOME A CLOSED LOW ON FRIDAY AND
TRAVEL SLOWLY SOUTHEAST INTO SOUTHERN CALIFORNIA ON FRIDAY AND
INTO ARIZONA EARLY SATURDAY MORNING. THIS WILL BRING A CHANCE FOR
RAIN AND SNOW SHOWERS TO THE SIERRA NEVADA THURSDAY AND
FRIDAY...AND A SLIGHT CHANCE OF SHOWERS TO THE KERN COUNTY DESERT
ON FRIDAY AS THE LOW SHIFTS SOUTH INTO SOUTHERN CALIFORNIA. THE
ENSEMBLE MEAN TRENDS HAVE BEEN VERY INCONSISTENT WITH THE TRACK OF
THIS LOW...GIVING FORECASTERS VERY LITTLE CONFIDENCE IN
MEASUREABLE RAIN...ESPECIALLY FOR THE DESERT.
ONCE THE UPPER LOW EXITS EAST...HIGH PRESSURE WILL BUILD OVER THE
REGION SATURDAY INTO SUNDAY...WITH THE OPERATIONAL AND ENSEMBLE
MEANS ALL IN AGREEMENT. THE BEGINNING OF NEXT WEEK LOOKS A BIT
LESS CERTAIN...AS NCEPS GLOBAL ENSEMBLE SHOWING VERY LOW
PREDICABILITY FOR THE UPPER LEVEL PATTERN FOR THE BEGINNING OF
NEXT WEEK. REGARDLESS...BOTH THE GFS AND ECMWF ARE INDICATING DRY
WEATHER.
LASTLY...WITH THE LIGHT RAIN SHOWERS EXPERIENCED IN THE VALLEY
TODAY...PATCHY FOG WILL ONCE AGAIN BE POSSIBLE THROUGH MANY VALLEY
LOCATIONS STARTING AS EARLY AS THURSDAY. PATCHY FOG WILL BE
POSSIBLE EACH NIGHT AND EARLY MORNING FROM THURSDAY INTO EARLY
NEXT WEEK.
&&
.AVIATION...
LOCAL MVFR VISIBILITIES AND MOUNTAIN OBSCURATIIONS IN SHOWERS
THROUGH 00Z WEDNESDAY. OTHERWISE VFR CONDITIONS FOR THE NEXT 24
HOURS.
&&
.AIR QUALITY ISSUES...
ON TUESDAY JANUARY 27 2015... FIREPLACE/WOOD STOVE BURNING STATUS
IS: NO BURNING UNLESS REGISTERED IN FRESNO... KERN... KINGS AND
TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 01-27 70:1934 39:1963 52:2012 25:1949
KFAT 01-28 78:1986 41:1963 50:2003 23:1975
KFAT 01-29 73:1960 43:2002 55:1911 24:1902
KBFL 01-27 75:1928 37:1963 51:2012 24:1904
KBFL 01-28 77:1988 47:1957 52:1981 27:1957
KBFL 01-29 74:1986 42:2002 54:1986 27:1903
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...RILEY
AVN/FW...BEAN
SYNOPSIS...RILEY
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
806 AM CST TUE JAN 27 2015
.SHORT TERM...
330 AM CST
THROUGH WEDNESDAY...
INFRARED AND WATER VAPOR SATELLITE LOOPS EARLY THIS MORNING HAVE
SHOWN THE LAST IN A SERIES OF SHEARED VORTICITY MAXIMA TO HAVE MOVED
SOUTHEAST OF THE AREA. LIGHT SNOW ASSOCIATED WITH THESE HAS MAINLY
ENDED. LOW-LEVEL WINDS HAVE ALSO SHIFTED MORE NORTHERLY AS A
SURFACE INDUCED TROUGH AXIS PULLS AWAY. THIS HAS ENDED THE LOW-
LEVEL ISENTROPIC ASCENT AND OMEGA WHICH HELPED TO INDUCE MUCH OF
THE FREEZING DRIZZLE LAST NIGHT. SO WITH THAT HAVE CANCELLED THE
ADVISORY AS THE WIDESPREAD THREAT HAS ENDED GOING INTO THE RUSH
HOUR. ONE HOPEFULLY ONLY SMALL FLY IN THE OINTMENT TO THIS IS THE
CHANCE FOR FREEZING DRIZZLE LINGERING IN MAINLY LAKE AND COOK
COUNTIES...INCLUDING CHICAGO...AS WINDS TURN OFF THE LAKE EARLY
THIS MORNING STEERING IN SOME MARGINAL LAKE-INDUCED INSTABILITY.
THE MKX RADAR IS INDICATING LIGHT ECHOES MOVING WESTWARD THAT
DUAL-POL SUGGESTS IS FREEZING DRIZZLE. RAP PROFILES ARE ONLY
SATURATED ABOUT AS COOL AS -8C ADDING SUPPORT TO THAT. WITH NOT
EXPECTING A SITUATION SUCH AS LAST EVENING GIVEN THE TREATMENT ON
ROADS AND THE DIFFERENT MORE MESOSCALE/LOCALIZED INDUCED
LIFT...FEEL BETTER GOING WITH AN SPS IF NEEDED. EXPECT THE CHANCES
TO END BY 10 AM OR SO AS DRIER AIR CONTINUES TO ADVECT WESTWARD
OVER THE LAKE SEEN BY DEW POINTS NEAR 10F ON THE MICHIGAN SHORE
ALONG WITH AN EAST WIND.
CLOUDS SHOULD BE SLOW TO CLEAR TODAY GIVEN THE CURRENT EXPANSIVENESS
TO THE NORTH AND THE CYCLONIC FLOW CONTINUING THROUGH THIS
MORNING...AS WELL AS AFOREMENTIONED LAKE-ORIENTED FLOW INTO
NORTHEAST ILLINOIS. MESOSCALE MODEL MOISTURE/CONDENSATE FIELDS
INDICATE CLOUDS LINGERING THE LONGEST ACROSS THE ILLINOIS PART OF
THE CWA WITH INDIANA EXPERIENCING NORTHEASTERLY DRY ADVECTION.
HAVE HIGHS ONLY A FEW DEGREES WARMER THAN CURRENT EARLY MORNING
VALUES GIVEN THIS THOUGHT PROCESS. CONFIDENCE IS LOW ON WHETHER
CLEARING OCCURS AREAWIDE LATE THIS AFTERNOON AND EVENING AS
GUIDANCE WOULD SUGGEST...PLUS THERE WILL LIKELY BE CIRRUS
SPREADING IN TOO. THIS INTRODUCES BUST POTENTIAL IN LOW
TEMPERATURES OVER NORTH CENTRAL ILLINOIS WHERE LOW TEENS TO MID
20S COULD OCCUR DEPENDING ON CLOUDS. FEEL MORE CONFIDENT NORTHWEST
INDIANA WILL BE MOSTLY CLEAR AND TOUCH SOME OF THOSE LOWER TO MID
TEENS.
DURING THE DAY WEDNESDAY...A THERMAL RIDGE BUILDS INTO THE AREA AND
EXPECTING AT LEAST SOME SUNSHINE AS SOUTHWESTERLY LOW-LEVEL FLOW
WILL BE ENOUGH TO ADVECT OUT ANY RESIDUAL LOW CLOUDS. THE WARMEST
PART OF THE THERMAL RIDGE REACHES US MORE SO WEDNESDAY NIGHT AND
CLIMATOLOGY FOR FORECAST 925MB TEMPERATURES WOULD KEEP
SURFACE READINGS IN THE 30S FOR MOST OF THE CWA ESPECIALLY WITH
SOME SNOW COVER ALBEIT MINIMAL.
MTF
&&
.LONG TERM...
330 AM CST
WEDNESDAY NIGHT THROUGH MONDAY...
THE NEXT CHANCE FOR PRECIPITATION IS WEDNESDAY NIGHT AND
THURSDAY...AND CONFIDENCE HAS FURTHER INCREASED THAT THIS WILL BE A
LIGHT PRECIPITATION EVENT...AS WELL AS ONE WITH ONLY LIQUID
WEDNESDAY NIGHT IF PRECIPITATION DEVELOPS OVER OUR AREA. A CLOSED
UPPER LOW NEAR LOS ANGELES EARLY THIS MORNING IS STILL FORECAST TO
GET CAUGHT IN THE WESTERLIES AND DAMPEN THE STRONG UPPER RIDGE IN
PLACE OVER THE ROCKIES. A GRADUAL PHASING WITH A NORTHERN STREAM
PROGRESSIVE WAVE IS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY
OVER THE GREAT LAKES REGION. WHILE THE 27.00 GFS IS MORE
AGGRESSIVE WITH THIS PHASING THAN OTHER 27.00 GUIDANCE...IT ONLY
BRINGS A LITTLE MORE OOMPH FOR PRECIP HERE. THE THERMAL RIDGE
MENTIONED IN THE SHORT TERM SECTION FOR WEDNESDAY IS 2C-6C AT
850-925MB AND SURFACE TEMPERATURES ARE NOT LIKELY TO DROP GIVEN
THE SOUTHERN FLOW AND INCREASING CLOUDS...SO HAVE CHANCES OF RAIN
AND DRIZZLE WEDNESDAY NIGHT AS MOISTURE TRANSPORT DEVELOPS. ON
THURSDAY...TRANSITION TO A LIGHT RAIN AND SNOW MIX AND AT THIS
POINT WPC AND OURSELVES REALLY HAVE NO ACCUMULATIONS FORECAST.
HAVE STILL TRIED TO TAKE INTO ACCOUNT SOME POSSIBLE SLOWING IN THE
FORECAST GIVEN THE CURRENT SIGNIFICANT CLOSED SYSTEM OFF THE
NORTHEAST U.S...AND KEPT PRECIP CHANCES INTO THURSDAY AFTERNOON.
THE PROGRESSIVE ACTIVE FLOW PATTERN IS FORECAST TO CONTINUE INTO
THE WEEKEND...WITH STRONG HIGH PRESSURE ON FRIDAY GIVING WAY TO
PRECIPITATION CHANCES THIS WEEKEND. ANOTHER CLOSED LOW OVER THE
FAR SOUTHWESTERN U.S. IS FORECAST TO MOVE GRADUALLY EASTWARD AND
LOOKS TO BE ABLE TO TAP INTO GULF AND EASTERN PACIFIC MOISTURE.
WITH A CUT-OFF FEATURE THIS COULD END UP SLOWING AND CERTAINLY
CHANGING IN EVOLUTION. GUIDANCE DISAGREES HOW ANY NORTHERN STREAM
DISTURBANCE MAY AID TO PULL SOME OF THIS MOISTURE OVER OUR AREA.
AT THIS TIME THIS LOOKS TO BE A POSSIBLY LONG DURATION BUT LIGHT
INTENSITY QPF EVENT AT THIS LATITUDE. GIVEN THE FEATURES AT PLAY
AND CURRENT PATTERN WE ARE IN...ITS JUST WAY TOO EARLY AS
POTENTIAL COULD GO EITHER WAY FROM THAT SOLUTION. CONFIDENCE IS A
LITTLE HIGHER IN THAT IT WOULD PROBABLY BE A MAINLY SNOW EVENT IF
IT WERE TO OCCUR. GUIDANCE IS IN BETTER AGREEMENT THAN 24 HOURS
AGO WITH A CANADIAN/MODIFIED ARCTIC AIR MASS BEING TAPPED IN THE
WAKE OF THIS SYSTEM WITH POSSIBLY SINGLE DIGIT NIGHTTIME
TEMPERATURES DEPENDING ON IF ANY FRESH SNOW COVER CAN OCCUR.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* CIGS SCATTERING TO VFR LATER THIS AFTERNOON.
* NORTHEAST WINDS AROUND 10 KT TODAY...BECOMING LIGHT/VARIABLE
AGAIN THIS EVENING/OVERNIGHT.
RATZER/DEUBELBEISS
//DISCUSSION...UPDATED 12Z...
WEAK LOW PRESSURE SYSTEM CONTINUES TO PULL AWAY TO THE SOUTHEAST
THIS MORNING...WITH A LINGERING SURFACE TROUGH REMAINING THE FOCUS
FOR AN AREA OF LOW CLOUDS...MVFR FOG AND SOME PATCHY LIGHT
FREEZING DRIZZLE. MID-LEVEL DISTURBANCE OVERHEAD AND WILL MOVE OFF
TO THE SOUTHEAST THIS MORNING...WHICH ALONG WITH DRIER NORTHEAST
WINDS DEVELOPING ABOVE THE SURFACE SHOULD LEAD TO DIMINISHING
POTENTIAL FOR -FZDZ BY MID-MORNING. DRIER AIR FROM THE NORTHEAST
SHOULD ALSO WORK TO RAISE CIGS AND IMPROVE VIS THROUGH THE MORNING
AND EARLY AFTERNOON HOURS AS WELL. WEAK HIGH PRESSURE WILL SPREAD
ACROSS THE AREA FROM THE NORTHWEST THIS EVENING...WITH VFR
CONDITIONS...THOUGH RFD/DPA COULD SEE SOME SHALLOW FOG DEVELOP
OVERNIGHT.
NORTH-NORTHEAST WINDS EARLY THIS MORNING WILL BECOME MORE SOLIDLY
NORTHEAST DURING THE MORNING...AROUND 10 KT. WINDS WILL DIMINISH
TOWARD EVENING AS GRADIENT WEAKENS WITH APPROACH OF THE HIGH...
WITH LIGHT/VARIABLE WINDS THIS EVENING AND OVERNIGHT. WITH THE
HIGH SHIFTING SOUTHEAST OF THE AREA EARLY WEDNESDAY...SOUTH WINDS
WILL DEVELOP.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM IN TIMING IMPROVEMENT FROM MVFR TO VFR.
* HIGH IN WIND TRENDS.
RATZER/DEUBELBEISS
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...CHANCE OF RAIN/DRIZZLE. MVFR/IFR POSSIBLE.
THURSDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY/IFR POSSIBLE.
FRIDAY AND SATURDAY...PRIMARILY VFR. CHANCE OF SNOW SATURDAY
NIGHT.
SUNDAY...CHANCE OF LIGHT SNOW. IFR POSSIBLE.
MONDAY...MVFR CIGS POSSIBLE.
RATZER
&&
.MARINE...
213 AM CST
MARINE CONCERNS ON LAKE MICHIGAN ARE A PERIOD OF STRONG SOUTH WINDS
WEDNESDAY AFTERNOON AND NIGHT...THEN A SHIFT TO STRONG NORTH TO
NORTHWEST WINDS THURSDAY AFTERNOON INTO EARLY FRIDAY...WITH THE
POTENTIAL FOR A PERIOD OF NORTHWEST GALES ESPECIALLY THURSDAY
AFTERNOON AND THURSDAY EVENING.
IN THE NEAR TERM...RELATIVELY QUIET WEATHER ACROSS THE LAKE EARLY
THIS MORNING AS A WEAKENING SURFACE TROUGH OVER ILLINOIS AND THE
LOWER OHIO VALLEY CONTINUES TO MOVE OFF TO THE SOUTHEAST...ALLOWING
WEAK HIGH PRESSURE TO SETTLE ACROSS THE AREA FROM THE NORTH TODAY.
LOOKING TO THE WEST...AN AREA OF LOW PRESSURE DEVELOPING IN THE LEE
OF THE CANADIAN ROCKIES WILL SLIDE SOUTHEAST INTO THE PLAINS
THROUGH TONIGHT...THEN WILL MOVE SLOWLY EAST TOWARD LAKE MICHIGAN
WEDNESDAY AND WEDNESDAY NIGHT. IN RESPONSE TO PRESSURE FALLS AHEAD
OF THE LOW...THE GRADIENT WILL TIGHTEN ACROSS LAKE MICHIGAN
WEDNESDAY WITH SOUTH WINDS RAMPING UP INTO THE 30 KT RANGE BY LATE
AFTERNOON AND EVENING. WINDS WILL DIMINISH BRIEFLY EARLY THURSDAY
MORNING AS THE LOW PRESSURE CENTER AND COLD FRONTAL TROUGH CROSS THE
LAKE...BEFORE WINDS SHIFT TO THE NORTH-NORTHWEST AND INCREASE
QUICKLY BACK INTO THE 30-35 KT RANGE THURSDAY AFTERNOON. FORECAST
SOUNDINGS INDICATE THE POTENTIAL FOR GALES THURSDAY AFTERNOON AND
EVENING IN THE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND THE
DEPARTING LOW AND COLD FRONT. THESE STRONG WINDS WILL CONTINUE INTO
EARLY FRIDAY...BEFORE DIMINISHING AS A BROAD AREA OF HIGH PRESSURE
SPREADS INTO THE AREA BY FRIDAY EVENING. THE HIGH WILL SLOWLY MOVE
OFF TO THE EAST ON SATURDAY...WITH A WEAK LOW EXPECTED TO PASS
ACROSS THE NORTHERN LAKES SATURDAY NIGHT AND TRAIL A COLD FRONT
ACROSS LAKE MICHIGAN THROUGH SUNDAY.
FOR THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE WATERS SMALL CRAFT
ADVISORY CONDITIONS LOOK TO DEVELOP WEDNESDAY AFTERNOON AND CONTINUE
THROUGH THURSDAY MORNING...WITH A BRIEF BREAK BEFORE HIGH WIND/WAVE
CONDITIONS DEVELOP AGAIN BY EARLY THURSDAY AFTERNOON. HIGH WAVES
WOULD LIKELY LINGER THROUGH MUCH OF FRIDAY...ESPECIALLY ALONG THE
INDIANA SHORE EAST OF GARY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
541 AM CST TUE JAN 27 2015
.SHORT TERM...
330 AM CST
THROUGH WEDNESDAY...
INFRARED AND WATER VAPOR SATELLITE LOOPS EARLY THIS MORNING HAVE
SHOWN THE LAST IN A SERIES OF SHEARED VORTICITY MAXIMA TO HAVE MOVED
SOUTHEAST OF THE AREA. LIGHT SNOW ASSOCIATED WITH THESE HAS MAINLY
ENDED. LOW-LEVEL WINDS HAVE ALSO SHIFTED MORE NORTHERLY AS A
SURFACE INDUCED TROUGH AXIS PULLS AWAY. THIS HAS ENDED THE LOW-
LEVEL ISENTROPIC ASCENT AND OMEGA WHICH HELPED TO INDUCE MUCH OF
THE FREEZING DRIZZLE LAST NIGHT. SO WITH THAT HAVE CANCELLED THE
ADVISORY AS THE WIDESPREAD THREAT HAS ENDED GOING INTO THE RUSH
HOUR. ONE HOPEFULLY ONLY SMALL FLY IN THE OINTMENT TO THIS IS THE
CHANCE FOR FREEZING DRIZZLE LINGERING IN MAINLY LAKE AND COOK
COUNTIES...INCLUDING CHICAGO...AS WINDS TURN OFF THE LAKE EARLY
THIS MORNING STEERING IN SOME MARGINAL LAKE-INDUCED INSTABILITY.
THE MKX RADAR IS INDICATING LIGHT ECHOES MOVING WESTWARD THAT
DUAL-POL SUGGESTS IS FREEZING DRIZZLE. RAP PROFILES ARE ONLY
SATURATED ABOUT AS COOL AS -8C ADDING SUPPORT TO THAT. WITH NOT
EXPECTING A SITUATION SUCH AS LAST EVENING GIVEN THE TREATMENT ON
ROADS AND THE DIFFERENT MORE MESOSCALE/LOCALIZED INDUCED
LIFT...FEEL BETTER GOING WITH AN SPS IF NEEDED. EXPECT THE CHANCES
TO END BY 10 AM OR SO AS DRIER AIR CONTINUES TO ADVECT WESTWARD
OVER THE LAKE SEEN BY DEW POINTS NEAR 10F ON THE MICHIGAN SHORE
ALONG WITH AN EAST WIND.
CLOUDS SHOULD BE SLOW TO CLEAR TODAY GIVEN THE CURRENT EXPANSIVENESS
TO THE NORTH AND THE CYCLONIC FLOW CONTINUING THROUGH THIS
MORNING...AS WELL AS AFOREMENTIONED LAKE-ORIENTED FLOW INTO
NORTHEAST ILLINOIS. MESOSCALE MODEL MOISTURE/CONDENSATE FIELDS
INDICATE CLOUDS LINGERING THE LONGEST ACROSS THE ILLINOIS PART OF
THE CWA WITH INDIANA EXPERIENCING NORTHEASTERLY DRY ADVECTION.
HAVE HIGHS ONLY A FEW DEGREES WARMER THAN CURRENT EARLY MORNING
VALUES GIVEN THIS THOUGHT PROCESS. CONFIDENCE IS LOW ON WHETHER
CLEARING OCCURS AREAWIDE LATE THIS AFTERNOON AND EVENING AS
GUIDANCE WOULD SUGGEST...PLUS THERE WILL LIKELY BE CIRRUS
SPREADING IN TOO. THIS INTRODUCES BUST POTENTIAL IN LOW
TEMPERATURES OVER NORTH CENTRAL ILLINOIS WHERE LOW TEENS TO MID
20S COULD OCCUR DEPENDING ON CLOUDS. FEEL MORE CONFIDENT NORTHWEST
INDIANA WILL BE MOSTLY CLEAR AND TOUCH SOME OF THOSE LOWER TO MID
TEENS.
DURING THE DAY WEDNESDAY...A THERMAL RIDGE BUILDS INTO THE AREA AND
EXPECTING AT LEAST SOME SUNSHINE AS SOUTHWESTERLY LOW-LEVEL FLOW
WILL BE ENOUGH TO ADVECT OUT ANY RESIDUAL LOW CLOUDS. THE WARMEST
PART OF THE THERMAL RIDGE REACHES US MORE SO WEDNESDAY NIGHT AND
CLIMATOLOGY FOR FORECAST 925MB TEMPERATURES WOULD KEEP
SURFACE READINGS IN THE 30S FOR MOST OF THE CWA ESPECIALLY WITH
SOME SNOW COVER ALBEIT MINIMAL.
MTF
&&
.LONG TERM...
330 AM CST
WEDNESDAY NIGHT THROUGH MONDAY...
THE NEXT CHANCE FOR PRECIPITATION IS WEDNESDAY NIGHT AND
THURSDAY...AND CONFIDENCE HAS FURTHER INCREASED THAT THIS WILL BE A
LIGHT PRECIPITATION EVENT...AS WELL AS ONE WITH ONLY LIQUID
WEDNESDAY NIGHT IF PRECIPITATION DEVELOPS OVER OUR AREA. A CLOSED
UPPER LOW NEAR LOS ANGELES EARLY THIS MORNING IS STILL FORECAST TO
GET CAUGHT IN THE WESTERLIES AND DAMPEN THE STRONG UPPER RIDGE IN
PLACE OVER THE ROCKIES. A GRADUAL PHASING WITH A NORTHERN STREAM
PROGRESSIVE WAVE IS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY
OVER THE GREAT LAKES REGION. WHILE THE 27.00 GFS IS MORE
AGGRESSIVE WITH THIS PHASING THAN OTHER 27.00 GUIDANCE...IT ONLY
BRINGS A LITTLE MORE OOMPH FOR PRECIP HERE. THE THERMAL RIDGE
MENTIONED IN THE SHORT TERM SECTION FOR WEDNESDAY IS 2C-6C AT
850-925MB AND SURFACE TEMPERATURES ARE NOT LIKELY TO DROP GIVEN
THE SOUTHERN FLOW AND INCREASING CLOUDS...SO HAVE CHANCES OF RAIN
AND DRIZZLE WEDNESDAY NIGHT AS MOISTURE TRANSPORT DEVELOPS. ON
THURSDAY...TRANSITION TO A LIGHT RAIN AND SNOW MIX AND AT THIS
POINT WPC AND OURSELVES REALLY HAVE NO ACCUMULATIONS FORECAST.
HAVE STILL TRIED TO TAKE INTO ACCOUNT SOME POSSIBLE SLOWING IN THE
FORECAST GIVEN THE CURRENT SIGNIFICANT CLOSED SYSTEM OFF THE
NORTHEAST U.S...AND KEPT PRECIP CHANCES INTO THURSDAY AFTERNOON.
THE PROGRESSIVE ACTIVE FLOW PATTERN IS FORECAST TO CONTINUE INTO
THE WEEKEND...WITH STRONG HIGH PRESSURE ON FRIDAY GIVING WAY TO
PRECIPITATION CHANCES THIS WEEKEND. ANOTHER CLOSED LOW OVER THE
FAR SOUTHWESTERN U.S. IS FORECAST TO MOVE GRADUALLY EASTWARD AND
LOOKS TO BE ABLE TO TAP INTO GULF AND EASTERN PACIFIC MOISTURE.
WITH A CUT-OFF FEATURE THIS COULD END UP SLOWING AND CERTAINLY
CHANGING IN EVOLUTION. GUIDANCE DISAGREES HOW ANY NORTHERN STREAM
DISTURBANCE MAY AID TO PULL SOME OF THIS MOISTURE OVER OUR AREA.
AT THIS TIME THIS LOOKS TO BE A POSSIBLY LONG DURATION BUT LIGHT
INTENSITY QPF EVENT AT THIS LATITUDE. GIVEN THE FEATURES AT PLAY
AND CURRENT PATTERN WE ARE IN...ITS JUST WAY TOO EARLY AS
POTENTIAL COULD GO EITHER WAY FROM THAT SOLUTION. CONFIDENCE IS A
LITTLE HIGHER IN THAT IT WOULD PROBABLY BE A MAINLY SNOW EVENT IF
IT WERE TO OCCUR. GUIDANCE IS IN BETTER AGREEMENT THAN 24 HOURS
AGO WITH A CANADIAN/MODIFIED ARCTIC AIR MASS BEING TAPPED IN THE
WAKE OF THIS SYSTEM WITH POSSIBLY SINGLE DIGIT NIGHTTIME
TEMPERATURES DEPENDING ON IF ANY FRESH SNOW COVER CAN OCCUR.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* PERIOD OF IFR CIGS/MVFR VIS IN FOG AND PATCHY LIGHT FREEZING
DRIZZLE EARLY THIS MORNING.
* CIGS IMPROVING TO MVFR BY LATE MORNING...SCATTERING TO VFR LATER
THIS AFTERNOON.
* NORTHEAST WINDS AROUND 10 KT TODAY...BECOMING LIGHT/VARIABLE
AGAIN THIS EVENING/OVERNIGHT.
RATZER
//DISCUSSION...UPDATED 12Z...
WEAK LOW PRESSURE SYSTEM CONTINUES TO PULL AWAY TO THE SOUTHEAST
THIS MORNING...WITH A LINGERING SURFACE TROUGH REMAINING THE FOCUS
FOR AN AREA OF LOW CLOUDS...MVFR FOG AND SOME PATCHY LIGHT
FREEZING DRIZZLE. MID-LEVEL DISTURBANCE OVERHEAD AND WILL MOVE OFF
TO THE SOUTHEAST THIS MORNING...WHICH ALONG WITH DRIER NORTHEAST
WINDS DEVELOPING ABOVE THE SURFACE SHOULD LEAD TO DIMINISHING
POTENTIAL FOR -FZDZ BY MID-MORNING. DRIER AIR FROM THE NORTHEAST
SHOULD ALSO WORK TO RAISE CIGS AND IMPROVE VIS THROUGH THE MORNING
AND EARLY AFTERNOON HOURS AS WELL. WEAK HIGH PRESSURE WILL SPREAD
ACROSS THE AREA FROM THE NORTHWEST THIS EVENING...WITH VFR
CONDITIONS...THOUGH RFD/DPA COULD SEE SOME SHALLOW FOG DEVELOP
OVERNIGHT.
NORTH-NORTHEAST WINDS EARLY THIS MORNING WILL BECOME MORE SOLIDLY
NORTHEAST DURING THE MORNING...AROUND 10 KT. WINDS WILL DIMINISH
TOWARD EVENING AS GRADIENT WEAKENS WITH APPROACH OF THE HIGH...
WITH LIGHT/VARIABLE WINDS THIS EVENING AND OVERNIGHT. WITH THE
HIGH SHIFTING SOUTHEAST OF THE AREA EARLY WEDNESDAY...SOUTH WINDS
WILL DEVELOP.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM-HIGH IN CIG/VIS TRENDS THIS MORNING. MEDIUM IN TIMING
IMPROVEMENT FROM IFR TO MVFR AND MVFR TO VFR.
* HIGH IN WIND TRENDS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...CHANCE OF RAIN/DRIZZLE. MVFR/IFR POSSIBLE.
THURSDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY/IFR POSSIBLE.
FRIDAY AND SATURDAY...PRIMARILY VFR. CHANCE OF SNOW SATURDAY
NIGHT.
SUNDAY...CHANCE OF LIGHT SNOW. IFR POSSIBLE.
MONDAY...MVFR CIGS POSSIBLE.
RATZER
&&
.MARINE...
213 AM CST
MARINE CONCERNS ON LAKE MICHIGAN ARE A PERIOD OF STRONG SOUTH WINDS
WEDNESDAY AFTERNOON AND NIGHT...THEN A SHIFT TO STRONG NORTH TO
NORTHWEST WINDS THURSDAY AFTERNOON INTO EARLY FRIDAY...WITH THE
POTENTIAL FOR A PERIOD OF NORTHWEST GALES ESPECIALLY THURSDAY
AFTERNOON AND THURSDAY EVENING.
IN THE NEAR TERM...RELATIVELY QUIET WEATHER ACROSS THE LAKE EARLY
THIS MORNING AS A WEAKENING SURFACE TROUGH OVER ILLINOIS AND THE
LOWER OHIO VALLEY CONTINUES TO MOVE OFF TO THE SOUTHEAST...ALLOWING
WEAK HIGH PRESSURE TO SETTLE ACROSS THE AREA FROM THE NORTH TODAY.
LOOKING TO THE WEST...AN AREA OF LOW PRESSURE DEVELOPING IN THE LEE
OF THE CANADIAN ROCKIES WILL SLIDE SOUTHEAST INTO THE PLAINS
THROUGH TONIGHT...THEN WILL MOVE SLOWLY EAST TOWARD LAKE MICHIGAN
WEDNESDAY AND WEDNESDAY NIGHT. IN RESPONSE TO PRESSURE FALLS AHEAD
OF THE LOW...THE GRADIENT WILL TIGHTEN ACROSS LAKE MICHIGAN
WEDNESDAY WITH SOUTH WINDS RAMPING UP INTO THE 30 KT RANGE BY LATE
AFTERNOON AND EVENING. WINDS WILL DIMINISH BRIEFLY EARLY THURSDAY
MORNING AS THE LOW PRESSURE CENTER AND COLD FRONTAL TROUGH CROSS THE
LAKE...BEFORE WINDS SHIFT TO THE NORTH-NORTHWEST AND INCREASE
QUICKLY BACK INTO THE 30-35 KT RANGE THURSDAY AFTERNOON. FORECAST
SOUNDINGS INDICATE THE POTENTIAL FOR GALES THURSDAY AFTERNOON AND
EVENING IN THE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND THE
DEPARTING LOW AND COLD FRONT. THESE STRONG WINDS WILL CONTINUE INTO
EARLY FRIDAY...BEFORE DIMINISHING AS A BROAD AREA OF HIGH PRESSURE
SPREADS INTO THE AREA BY FRIDAY EVENING. THE HIGH WILL SLOWLY MOVE
OFF TO THE EAST ON SATURDAY...WITH A WEAK LOW EXPECTED TO PASS
ACROSS THE NORTHERN LAKES SATURDAY NIGHT AND TRAIL A COLD FRONT
ACROSS LAKE MICHIGAN THROUGH SUNDAY.
FOR THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE WATERS SMALL CRAFT
ADVISORY CONDITIONS LOOK TO DEVELOP WEDNESDAY AFTERNOON AND CONTINUE
THROUGH THURSDAY MORNING...WITH A BRIEF BREAK BEFORE HIGH WIND/WAVE
CONDITIONS DEVELOP AGAIN BY EARLY THURSDAY AFTERNOON. HIGH WAVES
WOULD LIKELY LINGER THROUGH MUCH OF FRIDAY...ESPECIALLY ALONG THE
INDIANA SHORE EAST OF GARY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
830 AM EST TUE JAN 27 2015
.SYNOPSIS...
ISSUED AT 828 AM EST TUE JAN 27 2015
SKIES WILL CLEAR TODAY WITH TEMPERATURES WARMING INTO THE MID TO
UPPER 20S. TEMPERATURES WILL RISE TO NEAR FREEZING ON WEDNESDAY
WITH PARTLY CLOUDY SKIES. THE NEXT CHANCE OF PRECIPITATION WILL
ARRIVE WEDNESDAY NIGHT AND THURSDAY WITH A WINTRY MIX EXPECTED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM EST TUE JAN 27 2015
ANOTHER RELATIVELY QUIET SHORT TERM BUT CLOUD CONCERNS AND POSSIBLE
FZDZ THIS MORNING MAKE FOR A FEW ISSUES. FAR WESTERN CWA SATURATED
OVERNIGHT WITH FLURRIES OR VERY LIGHT SNOW FALLING IN DOWNSHEAR SIDE
OF MID LEVEL JET AXIS. ADVISORY ISSUED LAST EVENING FOR FREEZING
DRIZZLE THAT NEVER REALLY MATERIALIZED OVER OUR AREA DUE TO
SATURATED DGZ AND SEEDER FEEDER MECHANISMS ALLOWING FOR SNOW CRYSTAL
GROWTH. HOWEVER...STILL A SLIGHT CONCERN FOR LIGHT FZDZ THROUGH
SUNRISE AS SATELLITE SHOWS WARMING CLOUD TOPS UPSTREAM ACROSS WI
MOVING QUICKLY SOUTH AND LOSS OF HIGHER SEED CLOUDS EXPECTED NEXT
FEW HOURS. HIRES MODEL SOUNDINGS INDEED SHOWING DGZ DRYING OUT EARLY
THIS MORNING IN THE WEST BUT LOW LEVELS ALSO DRYING. THUS CHANCES
FOR ANY PCPN WILL BE DIMINISHING BUT PCPN TYPE OF ANY RESIDUAL PCPN
COULD BE FZDZ. CALLS TO WHITE AND PULASKI COUNTY INDICATE NO
PROBLEMS FROM FZDZ OVERNIGHT AND LITTLE TO NO REPORTS OF FZDZ
UPSTREAM AT THIS HOUR. WITH ADVISORY SET TO EXPIRE AT 6AM ANYWAY
PLAN TO CANCEL EARLY AND HANDLE ANY SPOTTY FREEZING LIQUID
DEVELOPMENT WITH SPECIAL WEATHER STATEMENTS IF NEEDED.
DRY WEDGE IN LOWER LEVELS HAS REMAINED IN PLACE ACROSS REMAINDER OF
CWA WITH LIGHT EASTERLY FLOW AIDING IN DRY AIR ENTRAINMENT. THIS DRY
EASTERLY FLOW ALONG WITH SUBSIDENCE TODAY EXPECTED TO HELP BREAK UP
CLOUDS FROM NORTHEAST TO SOUTHWEST THROUGH THE DAY.
HOWEVER...SATELLITE SHOWS AREA OF STRATUS OVER WI MOVING SLOWLY
SOUTHWARD AND MODELS DO NOT HAVE A GOOD HANDLE ON THIS CLOUD COVER.
LOW LEVEL RH PROGS FROM VARIOUS MODELS ALL SEEM TO SUPPORT DRYING
TODAY FROM THE NORTHEAST BUT RUC13 HAS ALSO SHOWN A TENDENCY FOR
HIGHER RH ACROSS CENTRAL OH TO ADVECT WEST INTO OUR EASTERN AREA
THIS AFTERNOON. ALL THESE CLOUD ISSUES MAKE FOR DIFFICULT FORECAST
TODAY. MOST SURROUNDING OFFICES FAVORING THE CLEARING SCENARIO SO
WILL LEAN TOWARD THE DRYING AND BE OPTIMISTIC WITH SKIES BECOMING
PARTLY CLOUDY AND EVENTUALLY MOSTLY CLEAR TONIGHT. HIGH PRESSURE TO
THEN SLIDE ACROSS THE AREA TONIGHT WITH LIGHT WINDS AND MOSTLY CLEAR
SKIES. THIS SHOULD ALLOW GOOD RADIATIONAL COOLING AND TEMPS TO DROP
BACK TO SINGLE DIGITS EASTERN HALF AND LOWER TEENS WEST WHERE SOME
MID AND HIGH CLOUDS MAY SPILL OVER RIDGE.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM EST TUE JAN 27 2015
NEXT CLIPPER-TYPE SYSTEM STILL SLATED TO IMPACT THE AREA LATE
WEDNESDAY NIGHT INTO THURSDAY. THIS WAVE WILL ACTUALLY BE AIDED TO
SOME DEGREE BY ANOTHER VORT MAX LEFTOVER FROM OLD BAJA CUTOFF LOW
CURRENTLY BEING REABSORBED INTO THE MEAN WESTERLIES. STILL SOME
INCONSISTENCIES IN THE MODELS REGARDING WHERE EXACTLY THESE TWO
WAVES TRACK AND HOW THEY INTERACT BUT OUR AREA SHOULD SEE A PERIOD
OF DECENT PV ADVECTION/CVA THAT WILL GENERATE AT LEAST SOME FORCED
ASCENT AND LIGHT PRECIP. THE PROBLEM IS THAT UPPER JET SUPPORT IS
MARGINAL AT BEST AND LATEST CONSENSUS TRACK FORECAST KEEPS THE BEST
LOW LEVEL ISENTROPIC ASCENT AND FRONTOGENESIS GENERALLY NORTH OF OUR
AREA. FURTHERMORE...STRONG LOW LEVEL WAA WILL INTRODUCE A MELTING
LAYER ALOFT (AND EVENTUALLY AT THE SURFACE) THAT WILL MAKE
ACCUMULATING SNOW VERY DIFFICULT WITH A HODGEPODGE OF ALL DIFFERENT
PRECIP TYPES OVER SPACE AND TIME. IMPOSSIBLE TO CORRECTLY NAIL DOWN
EXACT TIMING AND LOCATION OF VARIOUS PRECIP TYPES THIS FAR OUT BUT
DID TRY TO PUT A "BEST GUESS" IN THE GRIDS FOR NOW...BASED ON
CONSENSUS OF FORECAST LOW TRACK AND THERMAL PROFILES. PREFERENCE
LIES WITH A GFS/ECMWF COMBO. NAM SURFACE TEMPS APPEAR TOO COLD AND
QPF AMOUNTS TOO LIGHT. GEM THERMAL PROFILES ARE DECENT BUT KEEPS
PRECIP LOCKED UP TOO FAR NORTH. SUPPOSE THIS IS POSSIBLE IF FORECAST
TRACK IS IN LARGE ERROR BUT SOLUTIONS HAVE BEEN FAIRLY STABLE THUS
FAR AND SUSPECT MOST AREAS WILL SEE AT LEAST SOME LIGHT PRECIP WITH
A MODEST PV ANOMALY PASSING DIRECTLY OVERHEAD. THIS IS ESPECIALLY
TRUE GIVEN SUPERB MOISTURE AVAILABILITY WITH 700MB MIXING RATIOS
OVER 4 G/KG AND PW VALUES AROUND 0.75 INCHES. AS FAR AS PRECIP
TYPES...EXPECT COLD SURFACE TEMPS TO SUPPORT FREEZING RAIN AT THE
ONSET...TRANSITIONING TO ALL RAIN FROM SOUTH TO NORTH EARLY THURSDAY
MORNING. LATENT HEAT RELEASE DUE TO FREEZING AND CONTINUAL WAA WITH
S/SW SURFACE WINDS SHOULD LEAD TO A NONDIURNAL TEMPERATURE TREND AND
A FAIRLY QUICK CHANGEOVER TO RAIN WITH MINIMAL ICE ACCUMULATION.
STILL COULD BE SOME SLICK ROADS DURING THE EARLY MORNING COMMUTE
THOUGH...ESPECIALLY NORTH OF US-30. ATYPICAL DIURNAL TEMP TREND
CONTINUES ON THURSDAY WITH HIGHS PROBABLY OCCURRING IN THE LATE
MORNING AND THEN FALLING THROUGH THE AFTERNOON AS COLDER AIR WRAPS
BACK AROUND EXITING LOW. THIS WILL LEAD TO A CHANGE BACK TO SNOW
FROM NORTH TO SOUTH WITH SOME TRANSITORY SLEET MIXING IN AS WELL.
EXPECT SNOW AMOUNTS AROUND AN INCH AT MOST WITH THE HIGHEST AMOUNTS
IN OUR FAR NORTHEAST. ANY ACCUMULATION OF FREEZING RAIN AT THE ONSET
WILL BE LESS THAN A TENTH OF AN INCH. SOME LIGHT LAKE EFFECT/
ENHANCED SNOW POSSIBLE THURSDAY NIGHT BUT BY AND LARGE EVENT WILL BE
WINDING DOWN BY THEN.
NEXT CHANCE OF SNOW LOOKS TO BE ON SUNDAY AS ELONGATED/POSITIVELY
TILTED TROUGH SWINGS THROUGH THE CENTRAL CONUS. MODELS HAVE SHOWN A
HIGH DEGREE OF VARIABILITY DURING THIS TIMEFRAME SO FORECAST
CONFIDENCE IS LOW. DID FOCUS THE POP FORECAST A BIT BUT WILL HOLD
OFF FOR A FEW MORE RUNS BEFORE LATCHING ONTO ANY SPECIFICS. STILL
LOOKS LIKE AT LEAST A GLANCING BLOW OF MUCH COLDER AIR BEHIND THIS
SYSTEM ON MONDAY. NUDGED THE FORECAST TOWARD COLDER RAW GUIDANCE
WITH HIGHS IN THE TEENS AND LOWS FLIRTING WITH 0F.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 625 AM EST TUE JAN 27 2015
LOW LEVEL EASTERLY FLOW HAS HELPED PUSH MVFR CIGS BACK EAST OF
KSBN SO TAF SITES NOW VFR. SATELLITE SHOWS MVFR AND IFR STILL
NORTH AND WEST OF AREA BUT TRAJECTORIES SUGGEST THESE WILL STAY
WEST OF TERMINALS. SATELLITE ALSO SHOWING CLEARING BEGINNING TO
WORK SOUTH THROUGH WESTERN MICHIGAN SO STAYED OPTIMISTIC WITH
CLEARING THIS MORNING AND VFR THROUGH THE PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...BENTLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
628 AM EST TUE JAN 27 2015
.SYNOPSIS...
ISSUED AT 410 AM EST TUE JAN 27 2015
SOME VERY LIGHT SNOW OR LIGHT FREEZING DRIZZLE WILL BE POSSIBLE
EARLY THIS MORNING ACROSS FAR WESTERN AND NORTHWESTERN INDIANA AS
WELL AS ILLINOIS. ANY PRECIPITATION IS EXPECTED TO DIMINISH
SHORTLY AFTER SUNRISE. HIGHS TODAY WILL BE IN THE UPPER 20S AND
30S WITH PARTLY TO MOSTLY CLOUDY SKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM EST TUE JAN 27 2015
ANOTHER RELATIVELY QUIET SHORT TERM BUT CLOUD CONCERNS AND POSSIBLE
FZDZ THIS MORNING MAKE FOR A FEW ISSUES. FAR WESTERN CWA SATURATED
OVERNIGHT WITH FLURRIES OR VERY LIGHT SNOW FALLING IN DOWNSHEAR SIDE
OF MID LEVEL JET AXIS. ADVISORY ISSUED LAST EVENING FOR FREEZING
DRIZZLE THAT NEVER REALLY MATERIALIZED OVER OUR AREA DUE TO
SATURATED DGZ AND SEEDER FEEDER MECHANISMS ALLOWING FOR SNOW CRYSTAL
GROWTH. HOWEVER...STILL A SLIGHT CONCERN FOR LIGHT FZDZ THROUGH
SUNRISE AS SATELLITE SHOWS WARMING CLOUD TOPS UPSTREAM ACROSS WI
MOVING QUICKLY SOUTH AND LOSS OF HIGHER SEED CLOUDS EXPECTED NEXT
FEW HOURS. HIRES MODEL SOUNDINGS INDEED SHOWING DGZ DRYING OUT EARLY
THIS MORNING IN THE WEST BUT LOW LEVELS ALSO DRYING. THUS CHANCES
FOR ANY PCPN WILL BE DIMINISHING BUT PCPN TYPE OF ANY RESIDUAL PCPN
COULD BE FZDZ. CALLS TO WHITE AND PULASKI COUNTY INDICATE NO
PROBLEMS FROM FZDZ OVERNIGHT AND LITTLE TO NO REPORTS OF FZDZ
UPSTREAM AT THIS HOUR. WITH ADVISORY SET TO EXPIRE AT 6AM ANYWAY
PLAN TO CANCEL EARLY AND HANDLE ANY SPOTTY FREEZING LIQUID
DEVELOPMENT WITH SPECIAL WEATHER STATEMENTS IF NEEDED.
DRY WEDGE IN LOWER LEVELS HAS REMAINED IN PLACE ACROSS REMAINDER OF
CWA WITH LIGHT EASTERLY FLOW AIDING IN DRY AIR ENTRAINMENT. THIS DRY
EASTERLY FLOW ALONG WITH SUBSIDENCE TODAY EXPECTED TO HELP BREAK UP
CLOUDS FROM NORTHEAST TO SOUTHWEST THROUGH THE DAY.
HOWEVER...SATELLITE SHOWS AREA OF STRATUS OVER WI MOVING SLOWLY
SOUTHWARD AND MODELS DO NOT HAVE A GOOD HANDLE ON THIS CLOUD COVER.
LOW LEVEL RH PROGS FROM VARIOUS MODELS ALL SEEM TO SUPPORT DRYING
TODAY FROM THE NORTHEAST BUT RUC13 HAS ALSO SHOWN A TENDENCY FOR
HIGHER RH ACROSS CENTRAL OH TO ADVECT WEST INTO OUR EASTERN AREA
THIS AFTERNOON. ALL THESE CLOUD ISSUES MAKE FOR DIFFICULT FORECAST
TODAY. MOST SURROUNDING OFFICES FAVORING THE CLEARING SCENARIO SO
WILL LEAN TOWARD THE DRYING AND BE OPTIMISTIC WITH SKIES BECOMING
PARTLY CLOUDY AND EVENTUALLY MOSTLY CLEAR TONIGHT. HIGH PRESSURE TO
THEN SLIDE ACROSS THE AREA TONIGHT WITH LIGHT WINDS AND MOSTLY CLEAR
SKIES. THIS SHOULD ALLOW GOOD RADIATIONAL COOLING AND TEMPS TO DROP
BACK TO SINGLE DIGITS EASTERN HALF AND LOWER TEENS WEST WHERE SOME
MID AND HIGH CLOUDS MAY SPILL OVER RIDGE.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM EST TUE JAN 27 2015
NEXT CLIPPER-TYPE SYSTEM STILL SLATED TO IMPACT THE AREA LATE
WEDNESDAY NIGHT INTO THURSDAY. THIS WAVE WILL ACTUALLY BE AIDED TO
SOME DEGREE BY ANOTHER VORT MAX LEFTOVER FROM OLD BAJA CUTOFF LOW
CURRENTLY BEING REABSORBED INTO THE MEAN WESTERLIES. STILL SOME
INCONSISTENCIES IN THE MODELS REGARDING WHERE EXACTLY THESE TWO
WAVES TRACK AND HOW THEY INTERACT BUT OUR AREA SHOULD SEE A PERIOD
OF DECENT PV ADVECTION/CVA THAT WILL GENERATE AT LEAST SOME FORCED
ASCENT AND LIGHT PRECIP. THE PROBLEM IS THAT UPPER JET SUPPORT IS
MARGINAL AT BEST AND LATEST CONSENSUS TRACK FORECAST KEEPS THE BEST
LOW LEVEL ISENTROPIC ASCENT AND FRONTOGENESIS GENERALLY NORTH OF OUR
AREA. FURTHERMORE...STRONG LOW LEVEL WAA WILL INTRODUCE A MELTING
LAYER ALOFT (AND EVENTUALLY AT THE SURFACE) THAT WILL MAKE
ACCUMULATING SNOW VERY DIFFICULT WITH A HODGEPODGE OF ALL DIFFERENT
PRECIP TYPES OVER SPACE AND TIME. IMPOSSIBLE TO CORRECTLY NAIL DOWN
EXACT TIMING AND LOCATION OF VARIOUS PRECIP TYPES THIS FAR OUT BUT
DID TRY TO PUT A "BEST GUESS" IN THE GRIDS FOR NOW...BASED ON
CONSENSUS OF FORECAST LOW TRACK AND THERMAL PROFILES. PREFERENCE
LIES WITH A GFS/ECMWF COMBO. NAM SURFACE TEMPS APPEAR TOO COLD AND
QPF AMOUNTS TOO LIGHT. GEM THERMAL PROFILES ARE DECENT BUT KEEPS
PRECIP LOCKED UP TOO FAR NORTH. SUPPOSE THIS IS POSSIBLE IF FORECAST
TRACK IS IN LARGE ERROR BUT SOLUTIONS HAVE BEEN FAIRLY STABLE THUS
FAR AND SUSPECT MOST AREAS WILL SEE AT LEAST SOME LIGHT PRECIP WITH
A MODEST PV ANOMALY PASSING DIRECTLY OVERHEAD. THIS IS ESPECIALLY
TRUE GIVEN SUPERB MOISTURE AVAILABILITY WITH 700MB MIXING RATIOS
OVER 4 G/KG AND PW VALUES AROUND 0.75 INCHES. AS FAR AS PRECIP
TYPES...EXPECT COLD SURFACE TEMPS TO SUPPORT FREEZING RAIN AT THE
ONSET...TRANSITIONING TO ALL RAIN FROM SOUTH TO NORTH EARLY THURSDAY
MORNING. LATENT HEAT RELEASE DUE TO FREEZING AND CONTINUAL WAA WITH
S/SW SURFACE WINDS SHOULD LEAD TO A NONDIURNAL TEMPERATURE TREND AND
A FAIRLY QUICK CHANGEOVER TO RAIN WITH MINIMAL ICE ACCUMULATION.
STILL COULD BE SOME SLICK ROADS DURING THE EARLY MORNING COMMUTE
THOUGH...ESPECIALLY NORTH OF US-30. ATYPICAL DIURNAL TEMP TREND
CONTINUES ON THURSDAY WITH HIGHS PROBABLY OCCURRING IN THE LATE
MORNING AND THEN FALLING THROUGH THE AFTERNOON AS COLDER AIR WRAPS
BACK AROUND EXITING LOW. THIS WILL LEAD TO A CHANGE BACK TO SNOW
FROM NORTH TO SOUTH WITH SOME TRANSITORY SLEET MIXING IN AS WELL.
EXPECT SNOW AMOUNTS AROUND AN INCH AT MOST WITH THE HIGHEST AMOUNTS
IN OUR FAR NORTHEAST. ANY ACCUMULATION OF FREEZING RAIN AT THE ONSET
WILL BE LESS THAN A TENTH OF AN INCH. SOME LIGHT LAKE EFFECT/
ENHANCED SNOW POSSIBLE THURSDAY NIGHT BUT BY AND LARGE EVENT WILL BE
WINDING DOWN BY THEN.
NEXT CHANCE OF SNOW LOOKS TO BE ON SUNDAY AS ELONGATED/POSITIVELY
TILTED TROUGH SWINGS THROUGH THE CENTRAL CONUS. MODELS HAVE SHOWN A
HIGH DEGREE OF VARIABILITY DURING THIS TIMEFRAME SO FORECAST
CONFIDENCE IS LOW. DID FOCUS THE POP FORECAST A BIT BUT WILL HOLD
OFF FOR A FEW MORE RUNS BEFORE LATCHING ONTO ANY SPECIFICS. STILL
LOOKS LIKE AT LEAST A GLANCING BLOW OF MUCH COLDER AIR BEHIND THIS
SYSTEM ON MONDAY. NUDGED THE FORECAST TOWARD COLDER RAW GUIDANCE
WITH HIGHS IN THE TEENS AND LOWS FLIRTING WITH 0F.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 625 AM EST TUE JAN 27 2015
LOW LEVEL EASTERLY FLOW HAS HELPED PUSH MVFR CIGS BACK EAST OF
KSBN SO TAF SITES NOW VFR. SATELLITE SHOWS MVFR AND IFR STILL
NORTH AND WEST OF AREA BUT TRAJECTORIES SUGGEST THESE WILL STAY
WEST OF TERMINALS. SATELLITE ALSO SHOWING CLEARING BEGINNING TO
WORK SOUTH THROUGH WESTERN MICHIGAN SO STAYED OPTIMISTIC WITH
CLEARING THIS MORNING AND VFR THROUGH THE PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LASHLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS DES MOINES IA
537 AM CST TUE JAN 27 2015
.SHORT TERM /TODAY/...
ISSUED AT 355 AM CST TUE JAN 27 2015
MAIN CONCERNS TODAY WILL BE TEMPS AND CLOUD COVER THROUGH THE
MORNING HOURS...AND PERHAPS A PORTION OF THE AFTERNOON EAST. TO
VARYING DEGREES...MODELS ALL HINT AT SOME CLOUDS MOVING SOUTHEAST
ALONG THE EASTERN EDGE OF THE H700 RIDGE CAUGHT IN THE NORTHWEST
FLOW EARLY TODAY. HOWEVER...NONE OF THE MODELS IS DOING VERY WELL.
THE HRRR AND NMM WRF MAY HAVE A SLIGHTLY BETTER HANDLE ON THE
SITUATION. EXAMINING THE UPPER LEVEL H700 RIDGE THROUGH THE DAY
TODAY SHOWS THAT IT IS LIKELY TO CONTINUE BUILDING EAST THROUGH THE
AFTERNOON HOURS...ENDING ANY CYCLONIC PORTION OF CIRCULATION WHICH
IS ASSOCIATED WITH THE LEFTOVER SYSTEM FROM YESTERDAY. AT 00Z TUE
THE H850 ANALYSIS SHOWED A PRONOUNCED WAVE TRACKING THROUGH EASTERN
IOWA BACK NORTH TOWARD MINNEAPOLIS...BUT NORTHWEST OF THERE THE FLOW
BECOMES MORE ANTICYCLONIC OVER THE EASTERN DAKOTAS. ANOTHER UPSTREAM
TROUGH IS ALREADY DEVELOPING WITH AN ATTENDANT WARM FRONT OVER THE
WESTERN DAKOTAS. SOME CLOUDS OVER SASKATCHEWAN AND MANITOBA MAY
TRACK SOUTHEAST TOWARD THE REGION THIS AFTERNOON BUT LIKELY ONLY
AFFECT THE FAR EASTERN COUNTIES WITH MID TO HIGH LEVEL CLOUDS. BASED
ON CLOUDS AND LATER TRAJECTORIES...COOLER HIGHS WILL BE HAD OVER THE
NORTHEAST HALF OF THE FORECAST AREA WHILE THE SOUTHWEST HALF WILL
REMAIN MILD FOR JANUARY...BUT NOT AS WARM AS YESTERDAY. WITH A
RATHER WEAK RIDGE AXIS PASSING OVER THE AREA TODAY WINDS WILL REMAIN
LIGHT. HIGHS WILL RANGE FROM THE UPPER 30S NORTHEAST TO THE UPPER
40S SOUTHWEST.
.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 355 AM CST TUE JAN 27 2015
AM EXPECTING MAX TEMPS FOR WED TO BE VERY SIMILAR TO MONDAY`S HIGHS.
A WARM FRONT WILL CUT ACROSS THE MIDDLE OF THE CWA...LEADING TO A
NOTABLE TEMP GRADIENT...FROM NW TO SE. LOW 40S EXPECTED IN NE CWA
AND UPPER 50S IN SW CWA. NAM MORE AGGRESSIVE WITH LOW LEVEL CLOUD
COVER AND THUS IS A COOL OUTLIER. NAM ALSO STILL THINKS THERE IS
SNOW ACROSS THE CWA SO AM DISCARDING NAM SOLUTION.
A VERY FAST MOVING SHORTWAVE TO IMPACT CWA THURSDAY MORNING. THROUGH
WATER VAPOR IMAGERY...THIS SHORTWAVE CAN BE EASILY PICKED UP COMING
ONTO THE CALIFORNIA COAST AT 06Z TUE. MODELS INITIALIZING WELL WITH
PLACEMENT OF THIS LOW AS IT COMES ONSHORE.
ADDITIONALLY...MODELS CONVERGING ON SOLUTION OF PUTTING THE WAVE
DIRECTLY OVER CENTRAL IOWA AT 06Z THU. THERE IS A SIZABLE DRY AIR
POCKET FROM AROUND 850MB TO 500MB WHICH WILL PREVENT CLOUD
THICKNESS FROM EXCEEDING 5 KFT AND...SUBSEQUENTLY...KEEP THIS
SYSTEM FROM PRODUCING ANYTHING BEYOND LIGHT PRECIP. HAVE BUMPED
UP TEMPS FROM PVS SHIFT. KMCW TO KEST GFS SOUNDINGS SUPPORT MAINLY
DZ/-RA...WITH A VERY NARROW WINDOW OF -IP TO -SN POSSIBLE FROM
AROUND 09Z TO 12Z. PROFILE DURING THIS TIME IS BELOW ZERO UNTIL
NEAR SFC...WHICH IS NOT ENOUGH WARM LAYER DEPTH TO FULLY MELT ALL
SNOW FLAKES. BY 12Z THU...THIS LOW WILL BE OVER NORTHERN ILLINOIS
AND STRONG CAA PLUS SUBSIDENCE WILL BE ADVECTED INTO OUR CWA.
THOUGH SUNSHINE EXPECTED...DAYTIME TEMPS TO ONLY WARM AROUND 3 TO
5 DEGREES FROM OVERNIGHT MINS DUE TO CAA.
THURSDAY`S WINDS ALSO WORTH MENTIONING. MODELS SHOWING 25 KT TO 30
KT WINDS RIGHT OFF THE DECK...APPROACHING 35 KT TO 40 KT TO THE TOP
OF THE MIXED LAYER. SFC PRESSURE GRADIENT OF 3MB/100KM TO SUPPORT
STRONG WINDS AT THE SFC. IN ALL...MAY APPROACH WIND ADVISORY
CRITERIA STARTING EARLY THU AM AND HEADLINE MAY BE WARRANTED IF THIS
SOLUTION HOLDS. A STRONG SFC HIGH WILL MOVE THROUGH THE MIDWEST
FRIDAY...KEEPING FRIDAY QUIET AND HELPING TO DECOUPLE WINDS HEADING
INTO SATURDAY.
FOR THIS WEEKEND...THE 00Z RUNS ARE HOLDING AS THEY ARE SHOWING AN
ALBERTA CLIPPER TYPE SYSTEM LOOKS TO PASS THROUGH THE GREAT LAKES
REGION. THERE WILL BE AN ATTENDANT COLD FRONT TO THIS LOW WHICH IS
BEING PROGGED TO PROPAGATE THROUGH THE CWA SUNDAY MORNING. THE
TIMING HAS CHANGED SOME FROM THE 12Z MON MODEL RUNS TO THE 00Z TUE
RUNS...WITH THE EURO AND GFS DROPPING BACK FROPA UNTIL AROUND 06Z
TO 12Z SUN. MODELS SATURATE THE SKIES FROM TOP DOWN IN ADVANCE OF
THIS SYSTEM...STARTING SATURDAY MORNING. PUSHING TIMING BACK SEEMS
REASONABLE...AS LOW LEVELS NOT SATURATED UNTIL AFTER 00Z SUN. THUS
HAVE PUSHED BACK POPS SLIGHTLY. SOUNDING PROFILE COMPLETELY
SATURATED AND WELL BELOW FREEZING SUNDAY MORNING. HAVE BEGUN TO
NUDGE SUNDAY MORNING POPS UPWARD...WITH FURTHER INCREASES
CERTAINLY POSSIBLE IF THE MODEL SOLNS CONTINUE TO HOLD.
THE PAST FEW MODEL RUNS HAVE CERTAINLY BEEN TRENDING DOWNWARD WITH
TEMPERATURES BEHIND THIS FRONT. ENSEMBLES HAVE 850 MB TEMPS DOWN TO
THE -12C TO -15C RANGE ACROSS THE CWA. SINGLE DIGIT TEMPERATURES
APPEAR VERY POSSIBLE MONDAY AND TUESDAY MORNING.
&&
.AVIATION...27/12Z
ISSUED AT 537 AM CST TUE JAN 27 2015
MAIN CONCERNS THROUGH THE PERIOD ARE LOW CLOUDS. CLOUDS TRAPPED
WITHIN A WEAK UPPER LEVEL RIDGE CONTINUE TO DRIFT SLOWLY SOUTHWEST
INTO THE NORTHEAST AND NORTHERN PORTIONS OF THE FORECAST AREA AT
1130Z. MEANWHILE THE UPPER LEVEL H700 RIDGE IS EXPECTED TO SLOWLY
DRIFT EAST...FORCING THE DECK OF IFR/MVFR CONDITIONS TO SLIDE EAST
AS WELL. THE RAP AND 06Z GFS SUGGEST THE DECK WILL HOLD ON LONGER
...ESPECIALLY NORTHEAST AT KMCW AND KALO. HAVE LENGTHENED CLOUD
RESIDENCE TIME THROUGH 18Z WITH GRADUAL SCT CONDITIONS RETURNING
AFT 18Z THERE. AT THIS TIME...WILL CONTINUE VFR CONDITIONS AT KDSM
AND KOTM WITH BRIEF PERIOD OF MVFR CIGS AT KFOD BETWEEN 15 AND
17Z. REMAINDER OF PERIOD STRONGER SOUTHEAST FLOW RETURNS WITH 12KT
SUSTAINED AND GUSTS AFT 07Z WEST AND NORTH SITES. /REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...REV
LONG TERM...KOTENBERG
AVIATION...REV
AREA FORECAST DISCUSSION
NWS JACKSON KY
1102 AM EST TUE JAN 27 2015
.UPDATE...
ISSUED AT 1101 AM EST TUE JAN 27 2015
CURRENT OBSERVATIONS ARE SHOWING LOW LEVEL CLOUD COVER AND A FEW
FLURRIES MOVING THROUGH EASTERN KENTUCKY BUT MAINLY OVER THE SOUTHERN
PORTION. MUCH OF THE HEAVIER RETURNS ON RADAR HAVE DISSIPATED AND THE
SNOW SHOWER ACTIVITY HAS DWINDLED SIGNIFICANTLY. STILL CAN RULE OUT A
SLIGHT VISIBILITY REDUCTION INTO THIS AFTERNOON WITH SOME FLURRY
ACTIVITY. HAVE UPDATED THE GRIDS AND REMOVED SNOW SHOWER WORDING BUT
WILL CONTINUE TO INCLUDE SOME ISOLATED TO SCATTERED FLURRIES
THROUGH THE AFTERNOON. HAVE ISSUED A NEW ZFP FOR THESE CHANGES BUT
OVERALL THE FORECAST IS ON TRACK.
UPDATE ISSUED AT 725 AM EST TUE JAN 27 2015
A NEW SNOW BAND DEVELOPED OVER THE BLUEGRASS AREA AND HAS NOW SLIPPED
SOUTHEAST INTO OUR CWA RIDING JUST A TAD NORTHEAST OF THE PREVIOUS
ONE. ONLY BELATEDLY DID THE HRRR CATCH ON TO THIS LATEST BAND...
THOUGH. ACCORDINGLY...HAVE UPDATED THE GRIDS TO REFLECT THE SNOW
MOVEMENT AND ADJUSTED THE LIGHT SNOW AMOUNTS. ALSO FINE TUNED
TEMPERATURES AND DEWPOINTS PER THE LATEST OBS AND TRENDS. THESE HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM EST TUE JAN 27 2015
07Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE OFF TO THE
NORTHEAST WHILE LOCALLY THE PRESSURE GRADIENT IS RATHER RELAXED AND
THIS IS LIMITING THE UPSLOPE COMPONENT OF THIS NIGHT/S SNOW THREAT.
THE MAIN BANDS OF SNOW ARE BEING PRIMARILY DRIVEN BY A SFC TROUGH
AXIS SPLITTING THE STATE AND A STREAM OF MID LEVEL ENERGY RUNNING
NORTH NORTHWEST TO THE SOUTH SOUTHEAST OVER PARTS OF CENTRAL AND
EASTERN KENTUCKY. ON RADAR...THIS BAND LINES UP WELL WITH THIS
ENERGY STREAM AND IS ALSO ABLE TO TAP INTO EXTRA MOISTURE FROM LAKE
MICHIGAN. THE SNOW ASSOCIATED WITH THIS HAS BEEN RELATIVELY LIGHT
WITH MOST SITES REPORTING SNOW SEEING 4SM OR BETTER VIS...THOUGH IT
IS LIKELY THAT UNDER THE HIGHEST RADAR RETURNS VIS IS LESS THAN 2
MILES. FOR THESE LOCATIONS...A COUPLE OF TENTHS OF AN INCH OR SO OF
ACCUMULATION WILL BE POSSIBLE WHILE MOST OTHER PLACES WILL SEE JUST A
THICK DUSTING OR LESS. AN SPS IS IN EFFECT FOR THIS AND IT WILL BE
CONTINUED THROUGH DAWN AND THE MORNING RUSH HOUR FOR GOOD MEASURE.
TEMPERATURES...MEANWHILE ARE IN THE MID TO UPPER 20S ACROSS THE AREA
WITH DEWPOINTS A DEGREE OR SO LOWER AND WINDS LIGHT TO CALM.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST AS A CLOSED LOW DEEPENS OFF THE NEW ENGLAND COAST AND
A STREAM OF ENERGY FLOWS NNW TO SSE OVER KENTUCKY AND INTO THE
BROADER EAST COAST TROUGH TODAY. THIS FLOW WILL BE NUDGED EAST BY A
MODERATELY STRONG RIDGE IN THE SOUTHERN STREAM CROSSING THE SOUTHERN
PLAINS LATER TONIGHT. THIS RIDGE WILL BE PUSHED SOUTH BY A DEVELOPING
TROUGH COMING OUT OF THE CENTRAL ROCKIES AND MOVING INTO THE CENTRAL
PLAINS LATER WEDNESDAY. GIVEN THE GOOD MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE FIRST PART OF THE
FORECAST AND A BLEND THEREAFTER.
SENSIBLE WEATHER WILL FEATURE A BATCH OF EARLY MORNING SNOW SHOWERS
TARGETING MAINLY THE CUMBERLAND VALLEY OF EASTERN KENTUCKY. A FEW
FLURRIES WILL THEN LINGER INTO EARLY AFTERNOON FOR FAR SOUTHEAST
PARTS OF THE CWA BEFORE ALSO COMING TO AN END BY EARLY EVENING AS THE
CLOUDS ATTEMPT TO CLEAR. THIS...ALONG WITH SOME CONTINUED CAA FROM
THE EAST COAST STORM...WILL MAKE FOR A CHILLY NIGHT WITH LOWS IN THE
TEENS FOR WEDNESDAY MORNING. DESPITE HIGH PRESSURE PASSING THROUGH...
A BATCH OF LOW CLOUDS COULD DEVELOP OVERNIGHT AND HUG OUR EASTERN
ZONES INTO DAWN WEDNESDAY...WHICH MAY SPARE THESE AREAS THE COLDEST
TEMPS. THIS LOW LEVEL MOISTURE WILL ALSO NEED TO BE WATCHED FOR A
POTENTIAL OF SPOTTY FREEZING DRIZZLE IF THE STRATUS GETS THICK
ENOUGH. FOR NOW...THOUGH...IT LOOKS LIKE THIS WILL NOT BE THE
CASE...BUT THE POTENTIAL IS THERE. OTHERWISE...THE APPROACH OF
ANOTHER NORTHERN PASSING SFC LOW WILL HELP TO WARM THE AREA UP ON
WEDNESDAY WITH TEMPS REBOUNDING INTO THE MID 30S NORTHEAST TO THE
LOWER 40S SOUTHWEST. HOWEVER...HIGH CLOUDS WILL START TO MOVE IN BY
AFTERNOON FROM THE NORTHWEST LIMITING SUNSHINE ONCE ANY LOW CLOUDS
BREAK UP.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THIS AFTERNOON BEFORE PLUGGING IN THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR...TERRAIN BASED...
ADJUSTMENTS TO HOURLY AND MINIMUM TEMPERATURES TONIGHT. AS FOR
POPS...ENDED UP CLOSE TO A COMBINATION OF THE WETTER MAV AND DRIER
MET TODAY WHILE AGREED WITH THE LOW POPS FROM ALL GUIDANCE TONIGHT
AND WEDNESDAY ACROSS EAST KENTUCKY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 AM EST TUE JAN 27 2015
THE PERIOD BEGINS WITH HIGH PRESSURE CENTERED TO THE NORTH AND EAST
WITH SOME WEAK UPPER LEVEL RIDGING ACROSS THE REGION. EYES TURN
QUICKLY TO APPROACHING SURFACE LOW ACROSS THE MIDWEST THAT IS
FORECAST TO PROGRESS EAST INTO THE GREAT LAKES. A COLD FRONT
EXTENDING SOUTH FROM THE LOW WILL BE THE DRIVER FOR CHANCES OF PRECIP
AS WE MOVE INTO THURSDAY MORNING INTO THURSDAY NIGHT. THEREFORE
WEDNESDAY NIGHT WILL BE MET WITH INCREASING CLOUDS AND CHANCES OF
PRECIP INCREASING AS WE MOVE TOWARD DAYLIGHT ON THURSDAY. THE PRECIP
WILL BRING A CHANCES OF SNOW OR RAIN/SNOW MIX THURSDAY MORNING BEFORE
CHANGING TO ALL RAIN LATE MORNING INTO THURSDAY AS WARMER AIR MAKES
ITS WAY INTO THE REGION. THIS IS ALSO EVIDENT IN THE SOUNDS AS DRYER
AIR IS SEEN IN THE UPPER LEVEL LEADING TO LESS ICE BY THURSDAY
AFTERNOON. OTHERWISE THIS LOW PRESSURE SYSTEM AND ASSOCIATED
SHORTWAVE WILL MOVE EAST THURSDAY NIGHT WITH LOW DEEPENING ACROSS THE
NORTHEAST US. HERE WE SWITCH TO WEST TO NORTHWEST FLOW AND THEREFORE
HAVE KEPT SOME POPS ACROSS EAST AND SOUTHEAST THURSDAY NIGHT INTO
EARLY FRIDAY. THIS WILL LIKELY MIX WITH OR CHANGE TO SNOW AS WE MOVE
THROUGH THE NIGHT. GIVEN LIMITED MOISTURE AT THIS POINT WOULD THINK
LITTLE TO ANY ACCUMULATIONS WOULD BE EXPECTED WITH BEST CHANCES
ACROSS THE HIGHER TERRAIN.
MOVING INTO FRIDAY EXPECT DECREASING CLOUDS AND HIGH PRESSURE TO DROP
SOUTH OUT OF THE UPPER PLAINS. THIS WILL USHER IN GENERALLY BELOW
NORMAL TEMPS FOR FRIDAY. THE QUESTION REMAINS FRIDAY NIGHT AS TO HOW
MUCH THE TEMPS BOTTOM OUT. RIGHT NOW WOULD SEEM LIKE BEST CHANCES FOR
DECOUPLING WOULD BE ACROSS THE NORTH AND FAR EASTERN PORTIONS OF THE
CWA. DID INTRODUCE SOME TEENS TO BETTER MATCH NEIGHBORING OFFICES.
AFTER THIS THE HIGH PRESSURE MOVES EAST WITH RETURN FLOW SATURDAY
WITH TEMPERATURES GENERALLY ABLE TO REBOUND INTO THE UPPER 30S TO
LOWER 40S.
THEN FOCUS SHIFTS TO NEXT SYSTEM DEVELOPING ACROSS THE SOUTHWEST US
AND PLAINS STATES. THIS LOW PRESSURE WILL EVENTUALLY GET PICK UP BY
NORTHERN STREAM SHORTWAVE AND PROGRESS EAST INTO THE MISSISSIPPI
RIVER VALLEY LATE SATURDAY NIGHT. WE DO INTRODUCE SLIGHT TO CHANCE
POPS SATURDAY NIGHT WITH SOME OF THIS MIXING WITH SNOW AND RAIN
BEFORE CHANGING TO ALL RAIN SUNDAY AS LOW PRESSURE DEEPENS ALONG AND
NEAR THE OHIO RIVER VALLEY THROUGH THE DAY SUNDAY. THIS RAIN WILL
ONCE AGAIN TRANSITION TO MIX AND SNOW SUNDAY EVENING AND SUNDAY
NIGHT FROM NORTH TO SOUTH AS COLDER AIR FILTERS INTO THE REGION
BEHIND THIS LOW. GIVEN THE MORE NORTHERN TRACK OF THIS SURFACE LOW
AND BEST QPF AHEAD OF COLDER AIR WOULD THINK THAT ACCUMULATIONS WOULD
BE LIGHT IN TERMS OF ANY SNOW WE ARE ABLE TO GET. KEEP IN MIND THIS
IS STILL IN THE FARTHER REACHES OF THE LONG TERM FORECAST AND WILL
HAVE TO BE FINE TUNED AS WE GET CLOSER TO THE EVENT. AFTER THIS
SYSTEM MOVES EAST WITH SOME NW FLOW SNOW SHOWERS CONTINUING ACROSS
THE EAST AND SOUTHEAST. OTHERWISE COLDER AIR CONTINUES TO FILTER INTO
THE REGION WITH TEMPERATURES STRUGGLING TO MAKE IT ABOVE FREEZING
MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 705 AM EST TUE JAN 27 2015
A STREAM OF SHORTWAVE ENERGY ALOFT WILL KEEP THE CHANCES OF SNOW IN
THE FORECAST THROUGH MID MORNING FOR MUCH OF EASTERN KENTUCKY. THE
EARLIER BANDS OF LIGHT SNOW SET UP MAINLY OVER THE SOUTHWEST PORTION
OF THE FORECAST AREA...BUT THE NEXT BATCH...AND LIKELY LAST ONE...
LOOKS TO PASS THROUGH THE AREA MORE TO THE NORTHEAST OF THE EARLIER
ONES WITH A BETTER CHANCE OF AFFECTING THE JKL/SYM/SJS TAF SITES.
HAVE UPDATED THESE WITH A TEMPO FOR SOME MVFR AND IFR CIGS AND MVFR
VIS WITH ANY SNOW SHOWERS THROUGH MID MORNING. THE REST OF THE AREA
WILL SEE THEIR CURRENT IFR CIGS IMPROVE TO MVFR SHORTLY AND THEN VFR
LIKELY BY 17Z. LOOKING AT THE TIME HEIGHT SERIES FOR TONIGHT DECIDED
TO ADD SOME IFR STRATUS IN THE EASTERN TAF SITES IN THE PREDAWN
HOURS. WINDS WILL GENERALLY BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHALLENBERGER
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
725 AM EST TUE JAN 27 2015
.UPDATE...
ISSUED AT 725 AM EST TUE JAN 27 2015
A NEW SNOW BAND DEVELOPED OVER THE BLUEGRASS AREA AND HAS NOW SLIPPED
SOUTHEAST INTO OUR CWA RIDING JUST A TAD NORTHEAST OF THE PREVIOUS
ONE. ONLY BELATEDLY DID THE HRRR CATCH ON TO THIS LATEST BAND...
THOUGH. ACCORDINGLY...HAVE UPDATED THE GRIDS TO REFLECT THE SNOW
MOVEMENT AND ADJUSTED THE LIGHT SNOW AMOUNTS. ALSO FINE TUNED
TEMPERATURES AND DEWPOINTS PER THE LATEST OBS AND TRENDS. THESE HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM EST TUE JAN 27 2015
07Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE OFF TO THE
NORTHEAST WHILE LOCALLY THE PRESSURE GRADIENT IS RATHER RELAXED AND
THIS IS LIMITING THE UPSLOPE COMPONENT OF THIS NIGHT/S SNOW THREAT.
THE MAIN BANDS OF SNOW ARE BEING PRIMARILY DRIVEN BY A SFC TROUGH
AXIS SPLITTING THE STATE AND A STREAM OF MID LEVEL ENERGY RUNNING
NORTH NORTHWEST TO THE SOUTH SOUTHEAST OVER PARTS OF CENTRAL AND
EASTERN KENTUCKY. ON RADAR...THIS BAND LINES UP WELL WITH THIS
ENERGY STREAM AND IS ALSO ABLE TO TAP INTO EXTRA MOISTURE FROM LAKE
MICHIGAN. THE SNOW ASSOCIATED WITH THIS HAS BEEN RELATIVELY LIGHT
WITH MOST SITES REPORTING SNOW SEEING 4SM OR BETTER VIS...THOUGH IT
IS LIKELY THAT UNDER THE HIGHEST RADAR RETURNS VIS IS LESS THAN 2
MILES. FOR THESE LOCATIONS...A COUPLE OF TENTHS OF AN INCH OR SO OF
ACCUMULATION WILL BE POSSIBLE WHILE MOST OTHER PLACES WILL SEE JUST A
THICK DUSTING OR LESS. AN SPS IS IN EFFECT FOR THIS AND IT WILL BE
CONTINUED THROUGH DAWN AND THE MORNING RUSH HOUR FOR GOOD MEASURE.
TEMPERATURES...MEANWHILE ARE IN THE MID TO UPPER 20S ACROSS THE AREA
WITH DEWPOINTS A DEGREE OR SO LOWER AND WINDS LIGHT TO CALM.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST AS A CLOSED LOW DEEPENS OFF THE NEW ENGLAND COAST AND
A STREAM OF ENERGY FLOWS NNW TO SSE OVER KENTUCKY AND INTO THE
BROADER EAST COAST TROUGH TODAY. THIS FLOW WILL BE NUDGED EAST BY A
MODERATELY STRONG RIDGE IN THE SOUTHERN STREAM CROSSING THE SOUTHERN
PLAINS LATER TONIGHT. THIS RIDGE WILL BE PUSHED SOUTH BY A DEVELOPING
TROUGH COMING OUT OF THE CENTRAL ROCKIES AND MOVING INTO THE CENTRAL
PLAINS LATER WEDNESDAY. GIVEN THE GOOD MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE FIRST PART OF THE
FORECAST AND A BLEND THEREAFTER.
SENSIBLE WEATHER WILL FEATURE A BATCH OF EARLY MORNING SNOW SHOWERS
TARGETING MAINLY THE CUMBERLAND VALLEY OF EASTERN KENTUCKY. A FEW
FLURRIES WILL THEN LINGER INTO EARLY AFTERNOON FOR FAR SOUTHEAST
PARTS OF THE CWA BEFORE ALSO COMING TO AN END BY EARLY EVENING AS THE
CLOUDS ATTEMPT TO CLEAR. THIS...ALONG WITH SOME CONTINUED CAA FROM
THE EAST COAST STORM...WILL MAKE FOR A CHILLY NIGHT WITH LOWS IN THE
TEENS FOR WEDNESDAY MORNING. DESPITE HIGH PRESSURE PASSING THROUGH...
A BATCH OF LOW CLOUDS COULD DEVELOP OVERNIGHT AND HUG OUR EASTERN
ZONES INTO DAWN WEDNESDAY...WHICH MAY SPARE THESE AREAS THE COLDEST
TEMPS. THIS LOW LEVEL MOISTURE WILL ALSO NEED TO BE WATCHED FOR A
POTENTIAL OF SPOTTY FREEZING DRIZZLE IF THE STRATUS GETS THICK
ENOUGH. FOR NOW...THOUGH...IT LOOKS LIKE THIS WILL NOT BE THE
CASE...BUT THE POTENTIAL IS THERE. OTHERWISE...THE APPROACH OF
ANOTHER NORTHERN PASSING SFC LOW WILL HELP TO WARM THE AREA UP ON
WEDNESDAY WITH TEMPS REBOUNDING INTO THE MID 30S NORTHEAST TO THE
LOWER 40S SOUTHWEST. HOWEVER...HIGH CLOUDS WILL START TO MOVE IN BY
AFTERNOON FROM THE NORTHWEST LIMITING SUNSHINE ONCE ANY LOW CLOUDS
BREAK UP.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THIS AFTERNOON BEFORE PLUGGING IN THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR...TERRAIN BASED...
ADJUSTMENTS TO HOURLY AND MINIMUM TEMPERATURES TONIGHT. AS FOR
POPS...ENDED UP CLOSE TO A COMBINATION OF THE WETTER MAV AND DRIER
MET TODAY WHILE AGREED WITH THE LOW POPS FROM ALL GUIDANCE TONIGHT
AND WEDNESDAY ACROSS EAST KENTUCKY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 AM EST TUE JAN 27 2015
THE PERIOD BEGINS WITH HIGH PRESSURE CENTERED TO THE NORTH AND EAST
WITH SOME WEAK UPPER LEVEL RIDGING ACROSS THE REGION. EYES TURN
QUICKLY TO APPROACHING SURFACE LOW ACROSS THE MIDWEST THAT IS
FORECAST TO PROGRESS EAST INTO THE GREAT LAKES. A COLD FRONT
EXTENDING SOUTH FROM THE LOW WILL BE THE DRIVER FOR CHANCES OF PRECIP
AS WE MOVE INTO THURSDAY MORNING INTO THURSDAY NIGHT. THEREFORE
WEDNESDAY NIGHT WILL BE MET WITH INCREASING CLOUDS AND CHANCES OF
PRECIP INCREASING AS WE MOVE TOWARD DAYLIGHT ON THURSDAY. THE PRECIP
WILL BRING A CHANCES OF SNOW OR RAIN/SNOW MIX THURSDAY MORNING BEFORE
CHANGING TO ALL RAIN LATE MORNING INTO THURSDAY AS WARMER AIR MAKES
ITS WAY INTO THE REGION. THIS IS ALSO EVIDENT IN THE SOUNDS AS DRYER
AIR IS SEEN IN THE UPPER LEVEL LEADING TO LESS ICE BY THURSDAY
AFTERNOON. OTHERWISE THIS LOW PRESSURE SYSTEM AND ASSOCIATED
SHORTWAVE WILL MOVE EAST THURSDAY NIGHT WITH LOW DEEPENING ACROSS THE
NORTHEAST US. HERE WE SWITCH TO WEST TO NORTHWEST FLOW AND THEREFORE
HAVE KEPT SOME POPS ACROSS EAST AND SOUTHEAST THURSDAY NIGHT INTO
EARLY FRIDAY. THIS WILL LIKELY MIX WITH OR CHANGE TO SNOW AS WE MOVE
THROUGH THE NIGHT. GIVEN LIMITED MOISTURE AT THIS POINT WOULD THINK
LITTLE TO ANY ACCUMULATIONS WOULD BE EXPECTED WITH BEST CHANCES
ACROSS THE HIGHER TERRAIN.
MOVING INTO FRIDAY EXPECT DECREASING CLOUDS AND HIGH PRESSURE TO DROP
SOUTH OUT OF THE UPPER PLAINS. THIS WILL USHER IN GENERALLY BELOW
NORMAL TEMPS FOR FRIDAY. THE QUESTION REMAINS FRIDAY NIGHT AS TO HOW
MUCH THE TEMPS BOTTOM OUT. RIGHT NOW WOULD SEEM LIKE BEST CHANCES FOR
DECOUPLING WOULD BE ACROSS THE NORTH AND FAR EASTERN PORTIONS OF THE
CWA. DID INTRODUCE SOME TEENS TO BETTER MATCH NEIGHBORING OFFICES.
AFTER THIS THE HIGH PRESSURE MOVES EAST WITH RETURN FLOW SATURDAY
WITH TEMPERATURES GENERALLY ABLE TO REBOUND INTO THE UPPER 30S TO
LOWER 40S.
THEN FOCUS SHIFTS TO NEXT SYSTEM DEVELOPING ACROSS THE SOUTHWEST US
AND PLAINS STATES. THIS LOW PRESSURE WILL EVENTUALLY GET PICK UP BY
NORTHERN STREAM SHORTWAVE AND PROGRESS EAST INTO THE MISSISSIPPI
RIVER VALLEY LATE SATURDAY NIGHT. WE DO INTRODUCE SLIGHT TO CHANCE
POPS SATURDAY NIGHT WITH SOME OF THIS MIXING WITH SNOW AND RAIN
BEFORE CHANGING TO ALL RAIN SUNDAY AS LOW PRESSURE DEEPENS ALONG AND
NEAR THE OHIO RIVER VALLEY THROUGH THE DAY SUNDAY. THIS RAIN WILL
ONCE AGAIN TRANSITION TO MIX AND SNOW SUNDAY EVENING AND SUNDAY
NIGHT FROM NORTH TO SOUTH AS COLDER AIR FILTERS INTO THE REGION
BEHIND THIS LOW. GIVEN THE MORE NORTHERN TRACK OF THIS SURFACE LOW
AND BEST QPF AHEAD OF COLDER AIR WOULD THINK THAT ACCUMULATIONS WOULD
BE LIGHT IN TERMS OF ANY SNOW WE ARE ABLE TO GET. KEEP IN MIND THIS
IS STILL IN THE FARTHER REACHES OF THE LONG TERM FORECAST AND WILL
HAVE TO BE FINE TUNED AS WE GET CLOSER TO THE EVENT. AFTER THIS
SYSTEM MOVES EAST WITH SOME NW FLOW SNOW SHOWERS CONTINUING ACROSS
THE EAST AND SOUTHEAST. OTHERWISE COLDER AIR CONTINUES TO FILTER INTO
THE REGION WITH TEMPERATURES STRUGGLING TO MAKE IT ABOVE FREEZING
MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 705 AM EST TUE JAN 27 2015
A STREAM OF SHORTWAVE ENERGY ALOFT WILL KEEP THE CHANCES OF SNOW IN
THE FORECAST THROUGH MID MORNING FOR MUCH OF EASTERN KENTUCKY. THE
EARLIER BANDS OF LIGHT SNOW SET UP MAINLY OVER THE SOUTHWEST PORTION
OF THE FORECAST AREA...BUT THE NEXT BATCH...AND LIKELY LAST ONE...
LOOKS TO PASS THROUGH THE AREA MORE TO THE NORTHEAST OF THE EARLIER
ONES WITH A BETTER CHANCE OF AFFECTING THE JKL/SYM/SJS TAF SITES.
HAVE UPDATED THESE WITH A TEMPO FOR SOME MVFR AND IFR CIGS AND MVFR
VIS WITH ANY SNOW SHOWERS THROUGH MID MORNING. THE REST OF THE AREA
WILL SEE THEIR CURRENT IFR CIGS IMPROVE TO MVFR SHORTLY AND THEN VFR
LIKELY BY 17Z. LOOKING AT THE TIME HEIGHT SERIES FOR TONIGHT DECIDED
TO ADD SOME IFR STRATUS IN THE EASTERN TAF SITES IN THE PREDAWN
HOURS. WINDS WILL GENERALLY BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
935 AM EST TUE JAN 27 2015
.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY AS IT TRACKS
NORTH NORTHEAST OFF THE NEW ENGLAND COAST THROUGH TONIGHT.
MEANWHILE...HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC
THROUGH MIDWEEK. A COLD FRONT WILL CROSS THE AREA THURSDAY
NIGHT...FOLLOWED BY HIGH PRESSURE THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WINTER WX ADVSRYS HAVE BEEN SCALED BACK THIS MORNG AS THE SNOW HAS
ENDED IN SOME AREAS. THIS TREND WILL CONTINUE THRU THE LATE MORNG
HRS. ALSO ADDED AN SPS FOR AREAS S OF THE ADVSRY AREA WHERE UP TO
ONE INCH OF ACCUMULATION IS PSBL...BUT MAINLY ON GRASSY SFCS.
PREVIOUS DISCUSSION...
QUICK UPDATE TO CLEAR MARYLAND EASTERN SHORE COUNTIES FROM WITNER
WX ADVISORY BASED ON RADAR TRENDS. GIVEN LATEST REPORTS AND
TRAFFIC CAMS IN METRO RIC/ORF AREAS, WILL CONTINUE THEM ELSWEHERE.
EARLY MORNING RADAR MOSAIC SHOWING NARROW BAND OF PCPN DROPPING
SOUTH FROM CENTRAL PA SOUTH INTO EASTERN/CENTRAL VA. VSBY AVGG
2-4SM IN SN, AND WE`VE RECEIVED QUITE A FEW REPORTS ~1 AND A FEW
IN THE 1 1/2 TO 2" ALONG THE NORTHERN NECK INTO THE PENINSULA.
TRAFFIC CAMS SHOWING AT LEAST A COATING INTO THE TIDEWATER AREA
(CONFIRMED BY LOCAL COOPERATIVE OBSERVER). WE WILL BE MAINTAINING
WINTER HEADLINES FOR A LITTLE LONGER, WITH THIS BAND OF SNSH WELL
HANDLED BY THE HRRR EARLY THIS MORNING. NOT EXPECTING ANY LOCALES
IN NORFOLK OR RICHMOND METRO AREAS WILL RECEIVE ANY MORE THAN AN
INCH...BUT WITH THE HEADLINE ALREADY IN PLACE AND THE POTENTIAL
FOR SNOW TO CAUSE SOME IMPACTS DURING THE MORNING COMMUTE...DON`T
FEEL DROPPING THE HEADLINES IS PRUDENT ATTM. WL REVISIT HEADLINES
AT 7AM UPDATE. DO EXPECT DAY CREW WILL BE ABLE TO CLEAR HEADLINES
SHORTLY AFTER 14Z IF NOT SOONER.
HAVE BUMPED POPS UP IN TO CATEGORICAL RANGE FOR COASTAL NE NC, AND
GRADUALLY TAPERED THEM OFF ALONG THE EASTERN SHORE BY MID-LATE
MORNING. DROPPED POPS INTO NO HIGHER THAN 20% BUT HAVE KEPT
FLURRIES IN THE FORECAST FOR FAR WESTERN ZONES, AS ACCUMS NOT
ANTICIPATED.
INTENSIFYING SFC LOW WILL CONTINUE TO LIFT NE INTO NEW ENGLAND
THROUGH TONIGHT. ALL POPS DROP OFF BY EARLY AFTN, WITH STRONG CAA
BRINGING BREEZY/WINDY CONDITIONS (25-30MPH GUSTS ALONG THE
COAST/ERN SHORE), AND HOLDING HIGHS IN THE MID TO UPPER 30S (~40
IN THE PIEDMONT) UNDER A CLOUDY TO MOSTLY CLOUDY SKY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED COASTAL LOW PULLS TOWARDS ATLANTIC
CANADA AS COLD SFC HIGH PRESSURE BUILDS IN FROM THE W. CLEARING
SKY AND GRADUALLY DIMINISHING NW WINDS WILL ALLOW EARLY MORNING
LOW TEMPS TO FALL INTO THE THE 20S FOR MOST, W/ WIND CHILLS IN THE
TEENS IN MOST LOCATIONS.
HIGH PRESSURE BUILDS OVER THE LOCAL AREA ON WEDNESDAY.
TEMPERATURES REMAIN COOL WITH SHALLOW MIXING AND A NNE WIND. HIGHS
ONLY RANGING FROM THE MID 30S OVER THE LWR ERN SHORE TO THE UPR
30S TO LWR 40S ELSEWHERE. DRY AGAIN FOR WED NIGHT WITH LOWS IN THE
20S TO NEAR 30 ALONG THE COAST.
RAIN CHCS INCREASE ACROSS THE AREA LATER THU/THU NGT AS NORTHERN
STREAM SHORTWAVE TROUGH TRACKS FROM THE UPPER MIDWEST ACROSS TO
THE GREAT LAKES, WITH THE ASSOCIATED SFC LOW PUSHING ACROSS THE
NORTHERN MID-ATLANTIC INTO NEW ENGLAND BY LATE THU NGT. DAY BEGINS
PARTLY CLOUDY WITH GRADUALLY INCREASING CLOUDS. BEST FORCING
REMAINS OFF TO THE NORTH, SO HAVE CAPPED POP AT NO HIGHER THAN 30%
FOR NOW. RAIN CHANCES DIMINISH THU NGT AS SFC COLD FRONT PUSHES
ACROSS THE AREA. FOR HIGHS, SW FLOW AHEAD OF THE FRONT WILL ALLOW
FOR A MODEST WARMUP WITH MAXIMA IN THE U30S ERN SHORE/NRN
NECK...LOWER TO MID 40S INLAND AND U40S FAR SOUTHERN ZONES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. HIGH PRESSURE BUILDS IN FROM THE
WEST FRIDAY AND SATURDAY. ANOTHER COLD FRONT APPROACHES FROM THE
NW AND THEN MOVES ACROSS THE REGION LATE SUNDAY. EURO HAS A QUICK
MOVING FRONTAL WAVE MOVE ACROSS THE CAROLINAS LATE SUNDAY AND OUT
TO SEA MONDAY. THERE WILL BE A CHC FOR RAIN OR SNOW WITH THIS
SYSTEM BUT CONFIDENCE FOR SIGNIFICANT WINTER WEATHER IS LOW AT
THIS POINT.
HIGH TEMPERATURES ARE FORECAST IN THE UPR 30S AND 40S THURSDAY
LOWERING TO MOSTLY 30S TO AROUND 40 SATURDAY THROUGH MONDAY. LOWS
ARE EXPECTED TO RANGE THROUGH THE 30S FRIDAY MORNING AND MOSTLY 20S
SATURDAY THROUGH MONDAY MORNINGS.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
SNOW SHOWERS AFFECTING THE TAF SITES AS OF 12Z...WITH EITHER LOW
MVFR OR IFR CONDITIONS THROUGHOUT. SOME VARIABILITY IS ANTICIPATED
IN CIGS/VSBYS THROUGH 15Z AND HAVE GONE WITH TEMPO IFR CONDITIONS
FOR MOST TAF SITES THROUGH 14-15Z. GUSTY N/NW WINDS TO AROUND 25
KT AT ORF/KECG...AROUND 20 KT ELSEWHERE.
CONDITIONS WILL GRADUALLY IMPROVE AFTER 15Z...WITH CIGS LIFTING
TO 1500-2500 FT THEREAFTER. WINDS SHIFT MORE TO THE NW AND REMAIN
GUSTY TO AROUND 20 KT.
OUTLOOK...VFR/DRY WEATHER IS EXPECTED TUE NIGHT THROUGH THU AFTN. A
WEAK SYSTEM MAY DROP CIGS AND VSBYS IN LIGHT RAIN THU NIGHT/EARLY
FRI.
&&
.MARINE...
UPDATE...DOWNGRADED THE GALE WARNING TO SCA FLAGS FOR NRN COASTAL
WATERS FROM FENWICK ISLAND TO PARRAMORE ISLAND. WIND GUSTS HAVE
STRUGGLED TO REACH 34KT OR GREATER AT SFC BUOYS. SCA FOR NRN WATERS
WILL NOW BE IN EFFECT THROUGH MIDNIGHT WEDNESDAY NIGHT...AFTER WHICH
WINDS AND PRIMARILY SEAS WILL DROP BELOW SCA THRESHOLDS.
PREVIOUS DISCUSSION...STRONG COASTAL LOW IS LOCATED ABOUT 225 MILES
EAST OF ATLANTIC CITY NJ AS OF 4 AM. THE SFC PRESSURE GRADIENT
REMAINS VERY TIGHT...ESPECIALLY ALONG THE ATLANTIC COAST. THE ADDED
CAA AND DIURNAL EFFECTS ARE CAUSING N-NW WINDS TO EXPERIENCE A BRIEF
SURGE IN SPEEDS. SEAS HAVE QUICKLY RISEN TO 8-12FT IN SRN COASTAL
WATERS AS WELL. THE SURGE IN WINDS/SEAS IS EXPECTED TO BE BRIEF...
LASTING THROUGH SUNRISE...AFTER WHICH WINDS WILL DIMINISH SLIGHTLY
AND SEAS WILL SLOWLY SUBSIDE THROUGH THIS AFTN TO 5-7FT SRN
WATERS/6-10FT NRN WATERS...AS THE LOW TRACKS NE AND AWAY FROM THE
MID ATLANTIC COAST. FOR TONIGHT...THE STRONG LOW TRACKS TWD THE
CANADIAN MARITIMES AS HIGH PRESSURE BUILDS OVER THE OHIO VALLEY...
KEEPING A TIGHT PRESSURE GRADIENT OVER THE WATERS. PRESSURE RISES
AROUND 3MB THIS EVENING (OCCURRING BTWN 21Z TODAY AND 06Z TONIGHT)...
INDICATE THAT ANOTHER NWLY SURGE WITH GUSTS AROUND 30KT IS POSSIBLE
THIS EVENING FOR THE BAY/OCEAN AS CAA AND WRAPAROUND SHORTWAVE
ENERGY TRAVERSE THE WATERS.
HIGH PRESSURE SLOWLY BUILDS INTO THE MID ATLANTIC REGION ON WED.
CONTINUED CAA WILL KEEP NW WINDS ELEVATED WITHIN SCA THRESHOLDS
OVER ALL WATERS THROUGH THE DAY. HOWEVER...SEAS WILL SHOW A MARKED
DECREASE TO 4-5FT BY WED AFTN. ONLY CHANGE MADE TO SCA FLAGS WAS
TO EXTEND CHES BAY AND SRN COASTAL WATERS THROUGH 10 PM WED
EVENING BEFORE WINDS/SEAS FALL BELOW SCA THRESHOLDS. SEAS CONTINUE
TO SUBSIDE THRU WED EVENING AS HIGH PRESSURE SLIDES OVER THE
WATERS. A CLIPPER SYSTEM APPROACHING THE REGION ON THU WILL SHUNT
THE HIGH OVER THE SE COAST. THE COLD FRONT ASSOCIATED WITH THE
CLIPPER IS THEN EXPECTED TO CROSS THE WATERS THU NIGHT...FOLLOWED
BY POTENTIALLY SOLID SCA CONDITIONS FRI/FRI NIGHT.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY FOR OCEAN CITY HAS BEEN CANCELLED...FELL
SHORT OF MINOR FLOODING THRESHOLDS AS WINDS SHIFTED FASTER THAN
EXPECTED FROM ONSHORE E/NE MON AFTN TO OFFSHORE N/NW. DEPARTURES
HAVE BEEN BETWEEN 1.5 AND 2 FT ABOVE ASTRONOMICAL TIDE. MDL
GUIDANCE SHOWS THE UPCOMING TIDE THIS AFTN REACHING ABOVE 4 FT
MLLW...BUT THIS APPEARS WELL OVERDONE GIVEN THE N/NW WIND
DIRECTION AND CURRENT OBS AND TRENDS. NAM- BASED CBOFS GUIDANCE IS
RUNNING ABOUT 2 FT HIGHER THAN REALITY...BUT IN TERMS OF TREND
SHOWS THE TIDE THIS AFTN TO BE SLIGHTLY LOWER THAN THE HIGH TIDE
EARLIER THIS MORNING THAT ONLY PEAKED AT 3.7 FT MLLW. HAVE ISSUED
A COASTAL FLOOD STATEMENT RATHER THAN AN ADVISORY AT THIS POINT
GIVEN THE UNFAVORABLE OFFSHORE WIND FLOW.
ACRS THE LOWER BAY DEPARTURES ARE ALSO RUNNING AS HIGH AS 1.5 TO 2
FEET...BUT THIS STILL LEADS TO TIDES FALLING AT LEAST 0.5 FT SHY
OF MINOR FLOODING THIS AFTN. DEPARTURES WILL FALL TONIGHT INTO WED
WITH NO FLOODING CONCERNS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ081-089-
093-096.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VAZ070-071.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ633-
635>638.
SMALL CRAFT ADVISORY UNTIL 10 PM EST WEDNESDAY FOR ANZ630>632-
634-654-656-658.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST WEDNESDAY NIGHT FOR
ANZ650-652.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAS/MAM
SHORT TERM...MAS/MAM
LONG TERM...LSA
AVIATION...LKB
MARINE...BMD
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
701 AM EST TUE JAN 27 2015
.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY AS IT TRACKS
NORTH NORTHEAST OFF THE NEW ENGLAND COAST THROUGH TONIGHT.
MEANWHILE...HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC
THROUGH MIDWEEK. A COLD FRONT WILL CROSS THE AREA THURSDAY
NIGHT...FOLLOWED BY HIGH PRESSURE THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
QUICK UPDATE TO CLEAR MARYLAND EASTERN SHORE COUNTIES FROM WITNER
WX ADVISORY BASED ON RADAR TRENDS. GIVEN LATEST REPORTS AND
TRAFFIC CAMS IN METRO RIC/ORF AREAS, WILL CONTINUE THEM ELSWEHERE.
PREVIOUS DISCUSSION...
EARLY MORNING RADAR MOSAIC SHOWING NARROW BAND OF PCPN DROPPING
SOUTH FROM CENTRAL PA SOUTH INTO EASTERN/CENTRAL VA. VSBY AVGG
2-4SM IN SN, AND WE`VE RECEIVED QUITE A FEW REPORTS ~1 AND A FEW
IN THE 1 1/2 TO 2" ALONG THE NORTHERN NECK INTO THE PENINSULA.
TRAFFIC CAMS SHOWING AT LEAST A COATING INTO THE TIDEWATER AREA
(CONFIRMED BY LOCAL COOPERATIVE OBSERVER). WE WILL BE MAINTAINING
WINTER HEADLINES FOR A LITTLE LONGER, WITH THIS BAND OF SNSH WELL
HANDLED BY THE HRRR EARLY THIS MORNING. NOT EXPECTING ANY LOCALES
IN NORFOLK OR RICHMOND METRO AREAS WILL RECEIVE ANY MORE THAN AN
INCH...BUT WITH THE HEADLINE ALREADY IN PLACE AND THE POTENTIAL
FOR SNOW TO CAUSE SOME IMPACTS DURING THE MORNING COMMUTE...DON`T
FEEL DROPPING THE HEADLINES IS PRUDENT ATTM. WL REVISIT HEADLINES
AT 7AM UPDATE. DO EXPECT DAY CREW WILL BE ABLE TO CLEAR HEADLINES
SHORTLY AFTER 14Z IF NOT SOONER.
HAVE BUMPED POPS UP IN TO CATEGORICAL RANGE FOR COASTAL NE NC, AND
GRADUALLY TAPERED THEM OFF ALONG THE EASTERN SHORE BY MID-LATE
MORNING. DROPPED POPS INTO NO HIGHER THAN 20% BUT HAVE KEPT
FLURRIES IN THE FORECAST FOR FAR WESTERN ZONES, AS ACCUMS NOT
ANTICIPATED.
INTENSIFYING SFC LOW WILL CONTINUE TO LIFT NE INTO NEW ENGLAND
THROUGH TONIGHT. ALL POPS DROP OFF BY EARLY AFTN, WITH STRONG CAA
BRINGING BREEZY/WINDY CONDITIONS (25-30MPH GUSTS ALONG THE
COAST/ERN SHORE), AND HOLDING HIGHS IN THE MID TO UPPER 30S (~40
IN THE PIEDMONT) UNDER A CLOUDY TO MOSTLY CLOUDY SKY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED COASTAL LOW PULLS TOWARDS ATLANTIC
CANADA AS COLD SFC HIGH PRESSURE BUILDS IN FROM THE W. CLEARING
SKY AND GRADUALLY DIMINISHING NW WINDS WILL ALLOW EARLY MORNING
LOW TEMPS TO FALL INTO THE THE 20S FOR MOST, W/ WIND CHILLS IN THE
TEENS IN MOST LOCATIONS.
HIGH PRESSURE BUILDS OVER THE LOCAL AREA ON WEDNESDAY.
TEMPERATURES REMAIN COOL WITH SHALLOW MIXING AND A NNE WIND. HIGHS
ONLY RANGING FROM THE MID 30S OVER THE LWR ERN SHORE TO THE UPR
30S TO LWR 40S ELSEWHERE. DRY AGAIN FOR WED NIGHT WITH LOWS IN THE
20S TO NEAR 30 ALONG THE COAST.
RAIN CHCS INCREASE ACROSS THE AREA LATER THU/THU NGT AS NORTHERN
STREAM SHORTWAVE TROUGH TRACKS FROM THE UPPER MIDWEST ACROSS TO
THE GREAT LAKES, WITH THE ASSOCIATED SFC LOW PUSHING ACROSS THE
NORTHERN MID-ATLANTIC INTO NEW ENGLAND BY LATE THU NGT. DAY BEGINS
PARTLY CLOUDY WITH GRADUALLY INCREASING CLOUDS. BEST FORCING
REMAINS OFF TO THE NORTH, SO HAVE CAPPED POP AT NO HIGHER THAN 30%
FOR NOW. RAIN CHANCES DIMINISH THU NGT AS SFC COLD FRONT PUSHES
ACROSS THE AREA. FOR HIGHS, SW FLOW AHEAD OF THE FRONT WILL ALLOW
FOR A MODEST WARMUP WITH MAXIMA IN THE U30S ERN SHORE/NRN
NECK...LOWER TO MID 40S INLAND AND U40S FAR SOUTHERN ZONES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. HIGH PRESSURE BUILDS IN FROM THE
WEST FRIDAY AND SATURDAY. ANOTHER COLD FRONT APPROACHES FROM THE
NW AND THEN MOVES ACROSS THE REGION LATE SUNDAY. EURO HAS A QUICK
MOVING FRONTAL WAVE MOVE ACROSS THE CAROLINAS LATE SUNDAY AND OUT
TO SEA MONDAY. THERE WILL BE A CHC FOR RAIN OR SNOW WITH THIS
SYSTEM BUT CONFIDENCE FOR SIGNIFICANT WINTER WEATHER IS LOW AT
THIS POINT.
HIGH TEMPERATURES ARE FORECAST IN THE UPR 30S AND 40S THURSDAY
LOWERING TO MOSTLY 30S TO AROUND 40 SATURDAY THROUGH MONDAY. LOWS
ARE EXPECTED TO RANGE THROUGH THE 30S FRIDAY MORNING AND MOSTLY 20S
SATURDAY THROUGH MONDAY MORNINGS.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
SNOW SHOWERS AFFECTING THE TAF SITES AS OF 12Z...WITH EITHER LOW
MVFR OR IFR CONDITIONS THROUGHOUT. SOME VARIABILITY IS ANTICIPATED
IN CIGS/VSBYS THROUGH 15Z AND HAVE GONE WITH TEMPO IFR CONDITIONS
FOR MOST TAF SITES THROUGH 14-15Z. GUSTY N/NW WINDS TO AROUND 25
KT AT ORF/KECG...AROUND 20 KT ELSEWHERE.
CONDITIONS WILL GRADUALLY IMPROVE AFTER 15Z...WITH CIGS LIFTING
TO 1500-2500 FT THEREAFTER. WINDS SHIFT MORE TO THE NW AND REMAIN
GUSTY TO AROUND 20 KT.
OUTLOOK...VFR/DRY WEATHER IS EXPECTED TUE NIGHT THROUGH THU AFTN. A
WEAK SYSTEM MAY DROP CIGS AND VSBYS IN LIGHT RAIN THU NIGHT/EARLY
FRI.
&&
.MARINE...
UPDATE...DOWNGRADED THE GALE WARNING TO SCA FLAGS FOR NRN COASTAL
WATERS FROM FENWICK ISLAND TO PARRAMORE ISLAND. WIND GUSTS HAVE
STRUGGLED TO REACH 34KT OR GREATER AT SFC BUOYS. SCA FOR NRN WATERS
WILL NOW BE IN EFFECT THROUGH MIDNIGHT WEDNESDAY NIGHT...AFTER WHICH
WINDS AND PRIMARILY SEAS WILL DROP BELOW SCA THRESHOLDS.
PREVIOUS DISCUSSION...STRONG COASTAL LOW IS LOCATED ABOUT 225 MILES
EAST OF ATLANTIC CITY NJ AS OF 4 AM. THE SFC PRESSURE GRADIENT
REMAINS VERY TIGHT...ESPECIALLY ALONG THE ATLANTIC COAST. THE ADDED
CAA AND DIURNAL EFFECTS ARE CAUSING N-NW WINDS TO EXPERIENCE A BRIEF
SURGE IN SPEEDS. SEAS HAVE QUICKLY RISEN TO 8-12FT IN SRN COASTAL
WATERS AS WELL. THE SURGE IN WINDS/SEAS IS EXPECTED TO BE BRIEF...
LASTING THROUGH SUNRISE...AFTER WHICH WINDS WILL DIMINISH SLIGHTLY
AND SEAS WILL SLOWLY SUBSIDE THROUGH THIS AFTN TO 5-7FT SRN
WATERS/6-10FT NRN WATERS...AS THE LOW TRACKS NE AND AWAY FROM THE
MID ATLANTIC COAST. FOR TONIGHT...THE STRONG LOW TRACKS TWD THE
CANADIAN MARITIMES AS HIGH PRESSURE BUILDS OVER THE OHIO VALLEY...
KEEPING A TIGHT PRESSURE GRADIENT OVER THE WATERS. PRESSURE RISES
AROUND 3MB THIS EVENING (OCCURRING BTWN 21Z TODAY AND 06Z TONIGHT)...
INDICATE THAT ANOTHER NWLY SURGE WITH GUSTS AROUND 30KT IS POSSIBLE
THIS EVENING FOR THE BAY/OCEAN AS CAA AND WRAPAROUND SHORTWAVE
ENERGY TRAVERSE THE WATERS.
HIGH PRESSURE SLOWLY BUILDS INTO THE MID ATLANTIC REGION ON WED.
CONTINUED CAA WILL KEEP NW WINDS ELEVATED WITHIN SCA THRESHOLDS
OVER ALL WATERS THROUGH THE DAY. HOWEVER...SEAS WILL SHOW A MARKED
DECREASE TO 4-5FT BY WED AFTN. ONLY CHANGE MADE TO SCA FLAGS WAS
TO EXTEND CHES BAY AND SRN COASTAL WATERS THROUGH 10 PM WED
EVENING BEFORE WINDS/SEAS FALL BELOW SCA THRESHOLDS. SEAS CONTINUE
TO SUBSIDE THRU WED EVENING AS HIGH PRESSURE SLIDES OVER THE
WATERS. A CLIPPER SYSTEM APPROACHING THE REGION ON THU WILL SHUNT
THE HIGH OVER THE SE COAST. THE COLD FRONT ASSOCIATED WITH THE
CLIPPER IS THEN EXPECTED TO CROSS THE WATERS THU NIGHT...FOLLOWED
BY POTENTIALLY SOLID SCA CONDITIONS FRI/FRI NIGHT.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY FOR OCEAN CITY HAS BEEN CANCELLED...FELL
SHORT OF MINOR FLOODING THRESHOLDS AS WINDS SHIFTED FASTER THAN
EXPECTED FROM ONSHORE E/NE MON AFTN TO OFFSHORE N/NW. DEPARTURES
HAVE BEEN BETWEEN 1.5 AND 2 FT ABOVE ASTRONOMICAL TIDE. MDL
GUIDANCE SHOWS THE UPCOMING TIDE THIS AFTN REACHING ABOVE 4 FT
MLLW...BUT THIS APPEARS WELL OVERDONE GIVEN THE N/NW WIND
DIRECTION AND CURRENT OBS AND TRENDS. NAM- BASED CBOFS GUIDANCE IS
RUNNING ABOUT 2 FT HIGHER THAN REALITY...BUT IN TERMS OF TREND
SHOWS THE TIDE THIS AFTN TO BE SLIGHTLY LOWER THAN THE HIGH TIDE
EARLIER THIS MORNING THAT ONLY PEAKED AT 3.7 FT MLLW. HAVE ISSUED
A COASTAL FLOOD STATEMENT RATHER THAN AN ADVISORY AT THIS POINT
GIVEN THE UNFAVORABLE OFFSHORE WIND FLOW.
ACRS THE LOWER BAY DEPARTURES ARE ALSO RUNNING AS HIGH AS 1.5 TO 2
FEET...BUT THIS STILL LEADS TO TIDES FALLING AT LEAST 0.5 FT SHY
OF MINOR FLOODING THIS AFTN. DEPARTURES WILL FALL TONIGHT INTO WED
WITH NO FLOODING CONCERNS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ081-
089>091-093>098.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
VAZ073>078-084>086-099-100.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VAZ063-064-070>072-082-083.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST WEDNESDAY FOR ANZ630>632-
634-654-656-658.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST WEDNESDAY NIGHT FOR
ANZ650-652.
SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ633-
635>638.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MAS/MAM
LONG TERM...LSA
AVIATION...LKB
MARINE...BMD
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
626 AM EST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EST TUE JAN 27 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN HI AMPLITUDE RDG OVER THE ROCKIES AND DEEP TROF
OVER THE E SUPPORTING INTENSE WINTER STORM THAT IS IMPACTING NEW
ENGLAND. SHRTWV DIGGING SEWD WITHIN THIS NW FLOW/DEEPER CLDS THAT
CAUSED PERIOD OF SN LAST EVNG ARE NOW SE OF THE AREA...SO LINGERING
LIGHT SN OVER THE CENTRAL CWA IS DIMINISHING WITH THE APRCH OF
SHRTWV RDG AXIS/DNVA/DEEP LYR QVECTOR CNVGC AND DRIER MID LVL AIR
SHOWN ON THE 00Z INL/YPL RAOBS. THESE RAOBS SHOW SOME LLVL MSTR BLO
INVRN...SO PLENTY OF LO CLDS LINGER UPSTREAM OVER NRN MN/NW ONTARIO.
HOWEVER...WITH 00Z H85 TEMP ONLY -5C AT INL...THE INCOMING AIRMASS
IS NOT SUFFICIENTLY COLD TO SUPPORT LES. COLDER AND DRIER LLVL AIR
IS STILL PRESENT TOWARD THE E AND ARCTIC HI PRES IN QUEBEC...WITH
MOCLR SKIES REPORTED EARLY THIS MRNG AT NEWBERRY AND THE SAULT.
MAIN FCST CONCERNS FOR TODAY/TNGT WL BE CLD TRENDS/IMPACT ON TEMPS.
TODAY...UPR MI WL BE DOMINATED BY DNVA/DEEP LYR QVECTOR DVGC
ASSOCIATED WITH APRCHG SHRTWV RDG. SO AFTER ANY LINGERING LIGHT SN
ENDS EARLY THIS MRNG...THE DAY SHOULD BE DRY AS SFC RDG AXIS
EXTENDING WSW FM THE HI CENTER IN QUEBEC SHIFTS OVER THE CWA.
DESPITE THE MID LVL DRYING...LINGERING LLVL MSTR TRAPPED BLO
LOWERING/STRENGTHENING SUBSIDENCE INVRN WL LIKELY MAINTAIN GENERALLY
MOCLDY SKIES...IN LINE WITH UPSTREAM OBS. ONE EXCEPTION SHOULD BE
THE ERN CWA...WHERE LIGHT E WIND WL MAINTAIN THE LLVL DRY AIR AND
ALLOW FOR MOSUNNY SKIES. ANOTHER AREA THAT MAY SEE SOME CLRG IS NEAR
LK SUP OVER THE NW CWA WHERE THE LLVL SW FLOW ON THE NRN FLANK OF
THE SFC RDG AXIS WL DOWNSLOPE AND RESULT IN LOWERING THE INVRN BASE
FURTHER. GOING FCST HI TEMPS MAINLY IN THE 20S...COLDEST OVER THE
E AND WARMEST OVER THE W...LOOK TO BE IN GOOD SHAPE.
TNGT...A SHRTWV IS FCST TO TRACK THRU FAR NRN ONTARIO. ALTHOUGH
LINGERING SHRTWV RDG AXIS WL FORCE THIS DISTURBANCE TO PASS TOO FAR
TO THE N TO BRING PCPN TO ALL BUT FAR NRN LK SUP LATE...AN INCRSG
LLVL ACYC SW FLOW BTWN THE SFC RDG AXIS SLIDING OVER LOWER MI AND
FALLING MSLP IN ONTARIO ASSOCIATED WITH THE PASSING SHRTWV WL ADVECT
SOME DRIER AIR INTO THE CWA. THIS DRYING PLUS MORE LLVL SUBSIDENCE
ASSOCIATED WITH THE STRENGTHENING ACYC FLOW WL LIKELY BREAK UP THE
LO CLDS OVER MUCH OF THE CWA...ESPECIALLY OVER NW NEAR LK SUP WHERE
SW WINDS DOWNSLOPE. OVER THE E...THE SW FLOW OFF LK MI MIGHT DRAW
MORE LO CLDS INTO THAT AREA. DESPITE ANY CLRG OF THE LOWER CLDS...
STRONGER WINDS AND INCRSG MID/HI CLDS ON THE SRN FLANK OF THE
DISTURBANCE PASSING TO THE N WL LIMIT THE DIURNAL TEMP FALL. EXPECT
THE LOWEST MIN TEMPS OVER THE E...WHERE TEMPS WL FALL OFF QUICKLY IN
THE EVNG BEFORE THE WINDS HAVE A CHC TO PICK UP A BIT OR ANY
CLDS ROLL IN LATER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 502 AM EST TUE JAN 27 2015
MUCH OF THIS PERIOD WILL BE IMPACTED BY THE STEADY 500MB LOW OVER E
AND E CANADA. FROM TIME TO TIME IT WILL BE EXTENDING A TROUGH ACROSS
MUCH OF THE E HALF OF THE U.S.
WARMEST DAY THIS PERIOD WILL BE WEDNESDAY...WITH HIGHS GENERALLY 30-
35F ON LIGHT S FLOW. A LOW OVER N HUDSON BAY AND AN ADDITIONAL LOW
ACROSS THE N/CENTRAL PLAINS WILL PUSH A TROUGH OVER LAKE SUPERIOR
WEDNESDAY NIGHT. THIS WILL BRING THE BEST CHANCE OF WIDESPREAD SNOW
THROUGH THE LONG TERM PERIOD. HAVE ADJUSTED THE HWO MESSAGE TO
INCLUDE MAINLY THE TIP OF THE KEWEENAW AND E OF A LINE FROM MQT TO
ESC FOR THE POTENTIAL FOR MODERATE SNOW AMOUNTS. EXACT AMOUNTS VARY
SIGNIFICANTLY DEPENDING ON WHAT MODEL IS USED. FOR EXAMPLE AT KSAW
FOR WEDNESDAY NIGHT BUFKIT IS INDICATING THE POTENTIAL FOR 1-2IN
/00Z AND 06Z MODEL RUNS/. THE GFS IS SHOWING CLOSER TO 4-6IN. TAKING
A LOOK AT THE PRECIP FIELDS...THE 27/00Z ECMWF ALIGNS BETTER WITH
THE NAM WHILE THE CANADIAN IS CLOSER TO THE GFS. WILL CONTINUE A
FCST OF 2-5IN FOR MUCH OF THE CWA FROM WED THROUGH THURSDAY...WITH
ONLY 1-2IN ALONG THE WI BORDER. ONLY LIMITED SNOW IS EXPECTED OVER
THE UPSLOPE N CENTRAL AND E LOCATIONS BAST WEDNESDAY NIGHT/THURSDAY
MORNING.
THE TROUGH WILL WEAKEN THURSDAY/THURSDAY NIGHT AS THE LOW ACROSS THE
PLAINS SHIFTS TO S LOWER MI...AND THE NEW ENGLAND STATES.
HOWEVER...INCREASED N-NNW WINDS THURSDAY AFTERNOON LOOK
REASONABLE...WITH A 30-40KT LLJ SET UP...EXPECT ABOVE 925MB. THIS
WILL BE AS UPPER MI BECOMES STUCK BETWEEN THE EXITING LOW PUSHING
TOWARDS THE LOWER GREAT LAKES AND STRONG HIGH PRESSURE NEARING FROM
THE W. LOOK FOR PATCHY BLOWING SNOW TO DEVELOP THURSDAY ALONG LAKE
SUPERIOR...REDUCING VIS.
FRIDAY INTO EARLY SATURDAY... EXPECT THE HIGH MENTIONED ABOVE OVER
SASKATCHEWAN ON THURSDAY TO SINK ACROSS MN AND W LAKE SUPERIOR
FRIDAY MORNING...AND INTO THE OHIO VALLEY AND MID ATLANTIC STATES
SATURDAY. COLD AIR WILL BE OVERHEAD...WITH HIGHS IN THE LOW TO MID
TEENS FRIDAY. WHILE LOW LEVEL MOISTURE AROUND 800MB AND BELOW WILL
REMAIN TRAPPED UNDER THE LOWERING INVERSION THURSDAY-FRIDAY...AND
THE DGZ WILL BE WITHIN THIS MOISTURE LAYER...NO HEADLINE LES IS
ANTICIPATED. THIS WILL BE EVEN THROUGH SLR VALUES CLIMB BACK TO 20-
25:1. LESS THAN FAVORABLE W-SW WINDS FRIDAY EVENING SHOULD PUSH MUCH
IF NOT ALL OF THE LINGERING LIGHT SNOW SHOWERS BACK INTO LAKE
SUPERIOR. THE DRY WEATHER WILL ONLY BE TEMPORARY.
REST OF SATURDAY... A BRIEF TROUGH OF LOW PRESSURE WILL PUSH ACROSS
LAKE SUPERIOR ON SATURDAY...BEFORE STRONGER HIGH PRESSURE NEARS FROM
CENTRAL CANADA. TIMING THIS TROUGH IS IS STILL A BIT ROUGH...AS THE
GFS/ECMWF/CANADIAN DIFFER BY 6-12HRS. THE 27/00Z CANDIAN AND 26/12Z
ECMWF ARE PRETTY CONSISTANT...WHILE THE 27/00Z GFS IS ON THE SLOW
SIDE. EITHER WAY IT WILL USHER IN ANOTHER ROUND OF COLD AIR. HIGHS
SUNDAY SHOULD TOP OUT 10-17F.
SUNDAY THROUGH MONDAY... STRONGER AND COLD 30.9 INCH/1040-1050MB
HIGH PRESSURE OVER MUCH OF CENTRAL CANADA FRIDAY AND SATURDAY WILL
SLOWLY WEAKEN TO 30.6IN/1033-1037MB AS IT SETTLES ACROSS THE N
PLAINS/ UPPER MS VALLEY/UPPER GREAT LAKES TO START THE NEXT WORK
WEEK. HIGHS MONDAY MAY ONLY BE IN THE SINGLE DIGITS ABOVE ZERO.
THE HIGH WILL CONTINUE TO SINK SE ACROSS THE MID MS VALLEY/OHIO
VALLEY MONDAY NIGHT...AND MID ATLANTIC STATES TUESDAY-WEDNESDAY. THE
GFS IS PERSISTENT IN KEEPING THE HIGH IN PLACE...WHILE THE 26/12Z
ECMWF IS MORE PROGRESSIVE. MORE ON THIS WHEN WE START FCSTING FOR
MID NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 625 AM EST TUE JAN 27 2015
DRY AIR SLIPPING SLOWLY TO THE W IN THE LGT ESE FLOW ON THE WRN FLANK
OF HI PRES IN SE CANADA WL BRING PREDOMINANT VFR CONDITIONS TO CMX AND
SAW INTO THIS AFTN...WHEN A WSHFT TO THE SW ACCOMPANYING THE RDG MOVING
TO THE S WL DRAW MVFR CIGS PRESENT NEAR THE WI BORDER BACK OVHD. AS THE
SW WIND EVENTUALLY TAPS DRIER AIR TNGT AND THE INVRN BASE SINKS
FURTHER...THE LO CLDS/MVFR CIGS SHOULD GIVE WAY TO VFR CONDITIONS. FOR
IWD...MVFR CIGS SHOULD DOMINATE THRU THE DAY UNTIL LATE...WHEN LOWERING
INVRN BASE AND STRENGTHENING SW DOWNSLOPE WIND THAT WL ALSO TAP SOME
DRIER AIR WL BRING VFR CONDITIONS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST TUE JAN 27 2015
EXPECT S TO SW WINDS UNDER 20 KTS TO DOMINATE THRU WED AS A HI PRES
RIDGE OVER UPPER MI TODAY SINKS SLOWLY INTO THE LOWER GREAT LAKES.
ON THE NORTHERN FLANK OF A HI PRES RIDGE ORIENTED ACROSS THE CENTRAL
GREAT LAKES. LO PRES WILL THEN TRACK FROM THE MID MISSISSIPPI VALLEY
WED NIGHT TO THE LOWER LAKES THU NIGHT. BEHIND THE LOW...N TO NW
WINDS WILL INCREASE TO 20-30KT AND THEN TO GALE FORCE LATE THU AND
THU NIGHT. SINCE THESE STRONG WINDS WILL DRAW MUCH COLDER ARCTIC AIR
INTO THE UPPER LAKES...HEAVY FREEZING SPRAY WILL DEVELOP OVER MUCH
OF THE LAKE AND CONTINUE INTO FRI...WHEN WINDS/WAVES WILL DIMINISH
WITH THE CLOSER APPROACH OF CANADIAN HI PRES. ANOTHER DISTURBANCE
AND COLD FRONT MAY SWING ACROSS THE UPPER LAKES ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
924 AM EST TUE JAN 27 2015
.SYNOPSIS...
STRONG COASTAL LOW PRESSURE WILL SPREAD WIDESPREAD LIGHT TO
MODERATE SNOWS ACROSS THE EASTERN HALF OF THE FORECAST AREA TODAY
INTO EARLY THIS EVENING. HIGH PRESSURE RETURNS FOR LATER TONIGHT
THROUGH EARLY THURSDAY WITH SEASONABLY COLD AND MAINLY DRY
WEATHER. MORE LIGHT SNOWS ARE EXPECTED BY THURSDAY NIGHT INTO
FRIDAY AS LOW PRESSURE TRACKS EAST FROM THE GREAT LAKES STATES.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 905 AM EST TUESDAY...FCST CHALLENGE CONTS TO BE NORTHERN
EXTENT OF HEAVIER SNOW SHIELD ASSOCIATED WITH STRONG COASTAL LOW
PRESSURE. OVERALL EXPECTING MINIMAL IMPACTS ACROSS OUR CWA...WITH
HEAVIEST SNOW ACCUMULATIONS OF 4 TO 8 INCHES OVER THE CT RIVER
VALLEY...WITH 3 TO 5 INCHES CENTRAL VT AND 1 TO 3 INCHES IN THE
CHAMPLAIN VALLEY AND A DUSTING TO AN INCH OR SO ACROSS NORTHERN
NY. ALL WARNINGS AND ADVISORIES WILL REMAIN UP FOR NOW...BUT WILL
RECONSIDER AFTER REVIEWING ALL 12Z DATA BEFORE DROPPING ANY HEADLINES.
CRNT SFC ANALYSIS SHOWS 977MB LOW PRES NEAR THE
40/70 BENCHMARK WITH BUOY 44008 INDICATING RISING
PRES...SUGGESTING LOW PRES WL TRACK JUST EAST OF THIS
LOCATION...WHICH IS ABOUT A 25 MILE SHIFT EASTWARD. THIS WL RESULT
IN LESS IMPACT OF HEAVIER SNOWFALL ACRS OUR CWA...WITH GREATEST
IMPACTS ACRS CENTRAL/EASTERN VT THRU THIS AFTN. HAVE NOTED VSF VIS
AT 1/2SM IN MODERATE SNOW AND MPV/RUT DOWN TO 1SM IN LIGHT SNOW.
EXPECT THIS ACTIVITY TO EXPAND NW INTO THE CHAMPLAIN VALLEY BY
NOON TODAY. LATEST 12Z RAP AND 12Z NAM DOES SHOW MID/UPPER LVL
CIRCULATION CAPTURING SFC FEATURE AND RETROGRADING IT BACK
WESTWARD...TWD THE CAPE. THIS WL HAVE TO BE WATCHED...AS CRNT
RADAR SHOWS VERY INTENSE MESO BAND OF HEAVY SNOW ACRS
CENTRAL/EASTERN NEW ENGLAND...MOVING TWD OUR EASTERN CWA. THIS
BAND IS EXPECTED TO WEAKEN AS IT SLOWLY MOVES WESTWARD...WHILE BEST
MOISTURE AND UPPER LVL SUPPORT IS CLOSER TO THE COAST...ASSOCIATED
WITH SFC LOW PRES. ALSO...WITH 977MB LOW PRES OFF THE SOUTHERN NEW
ENGLAND COAST...EXPECT GUSTY NORTH WINDS TO DEVELOP HERE IN THE
CHAMPLAIN VALLEY AND SAINT LAWRENCE VALLEY...WHERE ENHANCED
CHANNELING WILL OCCUR. HAVE MENTION GUST TO 30 MPH OR SO. REST OF
FCST IN GOOD SHAPE.
PRIOR DISCUSSION FROM 321 AM EST TUESDAY...
INTENSE STORM CONTINUES TO DEVELOP OFF THE SOUTHEASTERN NEW
ENGLAND COAST NEAR NANTUCKET EARLY THIS MORNING WITH IMPRESSIVE
3-HOURLY PRESSURE FALLS NEAR 8 MB JUST NORTH OF THE 40N/-70W
BENCHMARK PER MOST RECENT MSAS ANALYSIS. A CLASSIC MILLER-B
EVOLUTION WITH INTENSE FRONTOGENETICAL BANDING FEATURES PIVOTING
SLOWLY NORTH AND WEST ACROSS ERN MA/CT/LI. THE DEVIL IS IN THE
DETAILS HOWEVER...ESPECIALLY IN REGARD TO TOTAL QPF/SNOWFALL
ACROSS OUR AREA. LATEST CAM OUTPUT INCLUDING THE RAP AND HRRR ALL
COMING ON BOARD WITH FAIRLY REALISTIC SOLUTIONS SHOWING WESTERN
EDGE OF STEADIER SNOWS WILL SLOWLY PIVOT NORTH AND WEST INTO VT
THROUGH THE COURSE OF THE MORNING/EARLY AFTERNOON WITH A RATHER
SHARP CUTOFF IN PCPN THE FURTHER NORTH AND WEST ONE PROGRESSES.
MOST PROBLEMATIC IS THE VERY COLD AND DRY ARCTIC AIRMASS IN PLACE
ACROSS OUR AREA. INDEED...LOW TO MID LEVEL DEWPOINTS REMAIN QUITE
LOW THIS MORNING AND THIS WILL TAKE SEVERAL HOURS OF MOISTENING
BEFORE STEADIER SNOWS REACH THE CENTRAL/NRN PORTIONS OF THE STATE.
REMAINING DRY IN NRN NY UNTIL LATE MORNING/EARLY AFTERNOON AND
MAINLY EASTERN PORTIONS OF CLINTON/ESSEX COUNTIES.
OLD RULE OF THUMB THAT USUALLY WORKS WELL HERE IS NOT TO GO TOO
EXTREME ON SNOWFALL TOTALS IF SOUTH COASTAL NEW ENGLAND IS BEARING
THE BRUNT OF THE STORM. RARELY TO WE SEE HEAVY SNOW SWATHS IN
EXCESS OF 200 MI AND THIS STORM WILL BE NO EXCEPTION. PAST
HISTORY ALSO SUGGESTS CLIPPER BOMBS GENERALLY UNDERPERFORM UP HERE
IN LIEU OF THE MORE CLASSIC GULF COAST/SOUTHEASTERN SEABOARD
SYSTEMS AS LONGITUDINAL DEVELOPMENT TYPICALLY OCCURS A BIT TOO FAR
EAST FOR US. IN ANY REGARD FELT THIS MORNINGS NAM HAD THE BEST
HANDLE ON CURRENT SITUATION AND USED ITS SOLUTION IN TANDEM WITH
BLENDED CAM QPF OUTPUT TO ARRIVE AT POP/SNOWFALL GRADIENTS ACROSS
OUR AREA. GFS IDEA BIASED ABOUT 50 MI TOO FAR SOUTH AND EAST AND
EURO QPF TOO SPREAD OUT WITH ITS COARSER RESOLUTION DESPITE A
FAIRLY ACCURATE DEPICTION OF LOW TO MID LEVEL FEATURES.
WHAT THIS ALL SPELLS IS A STEADY 5-10/6-12 INCH SNOWFALL FOR OUR
SOUTHERNMOST COUNTIES...WITH A FAIRLY QUICK DROP OFF IN SNOW
TOTALS NORTH AND WEST. A SW-NE ORIENTED BAND OF 3-7 INCHES STILL
PROGGED FROM ABOUT MIDDLEBURY NORTHEASTWARD THROUGH MONTPELIER AND
ST JOHNSBURY...AND A GENERAL 1-3 INCH SNOWFALL FROM ESSEX COUNTY
NY NORTHEAST INTO THE BURLINGTON/PLATTSBURGH VICINITY AND ST
ALBANS/FRANKLIN COUNTY. LITTLE IF ANY ACCUMULATION FROM A SARANAC
LAKE TO MALONE LINE WEST. THIS IS MORE OR LESS STAYING THE COURSE
AND WE`RE NOW INTO THE WAIT AND SEE TIMEFRAME TO SEE HOW THIS ALL
PANS OUT. ALL ADVISORIES/WARNINGS REMAIN IN PLACE WITH NO CHANGES
NEEDED AT THIS TIME.
BY TONIGHT OCCLUDED CYCLONE CONTINUES ITS TREK SLOWLY NORTHEAST
TOWARD YARMOUTH, NS WITH WESTERN EDGE OF PCPN GRADUALLY FADING AWAY
ACROSS OUR AREA AS DEEPER LIFT AND DYNAMICAL SUPPORT FOR PCPN WANE.
SOME LIGHT TAIL-END ACCUMULATIONS POSSIBLE NORTH AND
EAST...OTHERWISE TRENDING DRY OVERNIGHT. DID ADJUST LOW TEMPERATURES
A TAD MILDER THAN PREVIOUS FORECASTS GIVEN CONTINUED OVERCAST SKIES
AND NEAR NEUTRAL THERMAL ADVECTIVE PROCESSES...MAINLY POSITIVE
SINGLE DIGITS...LOCALLY A BIT COLDER FAR WEST WHERE SOME PARTIAL
CLEARING MAY OCCUR LATE.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
AS OF 321 AM EST TUESDAY...HIGH PRESSURE THEN BUILDS EAST INTO
THE REGION BY WEDNESDAY WITH SKIES TRENDING CLEAR TO PARTLY CLOUDY
THROUGH THE COURSE OF THE AFTERNOON. DRY WEATHER CONDITIONS
EXPECTED WITH BLENDED MOS NUMBERS SUPPORTING HIGH TEMPERATURES
GENERALLY IN THE TEENS...PERHAPS LOWER 20S FAR SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
AS OF 314 AM EST TUESDAY...DRY WEATHER TO START THE PERIOD AS
RIDGE OF HIGH PRESSURE AND ALOFT RESIDES OVER THE REGION WEDNESDAY
NIGHT. EARLY THURSDAY, THE RIDGE SLIDES EASTWARD WITH SOUTHERLY
FLOW DEVELOPING OVER THE REGION, INCREASING MOISTURE AND
MODERATING TEMPERATURES AHEAD OF A CLIPPER SYSTEM APPROACHING FROM
THE GREAT LAKES REGION. WHILE GFS AND ECMWF AGREE THAT
PRECIPITATION SHIELD WILL ENTER OUR WESTERN ZONES THURSDAY
AFTERNOON, THERE AREA DIFFERENCE REGARDING THE TRACK OF THE SFC
LOW AND THE PROGRESSION OF THE ASSOCIATED MID LEVEL TROUGH. THIS
LOW LOOKS TO BRING SNOW TO THE REGION THROUGH AT LEAST FRIDAY
EVENING. MID LEVEL TROUGH BECOMES NEGATIVELY TILTED ACCORDING TO
BOTH MODELS, THEREFORE AM FAVORING A SLOWER DEPARTURE OF
PRECIPITATION FROM NORTHEASTERN VERMONT AS DEPICTED BY THE ECMWF.
EXPECTING SOME LINGERING POPS INTO EARLY SATURDAY MORNING, BUT
NORTH/NORTHWEST FLOW BEHIND THIS SYSTEM WILL BRING IN DRIER AIR.
SO EXPECT SATURDAY TO BE MOSTLY DRY AT THIS POINT. AT THIS POINT,
EXPECT POTENTIAL SNOWFALL TOTALS TO RANGE FROM 2 TO 5 INCHES.
ANOTHER SYSTEM DEVELOPING IN THE MISSISSIPPI VALLEY WILL MOVE
NORTHEASTWARD LATE SUNDAY INTO MONDAY...BRINGING ANOTHER CHANCE
FOR SNOW FOR THE BEGINNING OF NEXT WEEK.
TEMPERATURES WEDNESDAY NIGHT WILL BE GENERALLY IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO. TEMPERATURES MODERATING IN THE
SOUTHERLY FLOW THURSDAY THROUGH FRIDAY WITH MAXES IN THE 20S AND
MINS IN THE TEENS TO L20S. BEHIND THE CLIPPER LOW, COLD AIR WILL
RETURN WITH MINS OF -15F TO ZERO FOR THE REST OF THE PERIOD. MAXES
WILL REACH SINGLE DIGITS TO MID TEENS SATURDAY THROUGH MONDAY.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
THROUGH 12Z WEDNESDAY...VFR CONDITIONS WILL DETERIORATE TO MVFR
AS SNOW SPREADS NORTHWESTWARD THIS MORNING. EXPECT MVFR
CONDITIONS AND SNOW TO MOVE INTO KRUT BETWEEN 12-15Z...KMPV 13-
15Z...KBTV/KPBG 15Z-17Z...AND KSLK 16Z-18Z. KMSS WILL BE FAR
ENOUGH NORTH AND WEST TO REMAIN VFR. SOME EMBEDDED MODERATE SNOW
IS POSSIBLE WITH IFR/LIFR CONDITIONS AFFECTING KRUT/KMPV 14Z-
22Z...KBTV/KPBG 17Z-21Z AND KSLK 18Z-23Z.
SNOW WILL LIGHTEN AND DIMINISH THIS EVENING WITH MOSTLY DRY
CONDITIONS SETTLING IN AFTER MIDNIGHT/05Z. EXPECT CONDITIONS TO
IMPROVE TO MVFR/VFR AS SNOWFALL COMES TO AN END.
NORTH TO NORTHEAST WINDS OF 6-12KTS WILL INCREASE AND BECOME
GUSTY AROUND 25KTS BY MID MORNING. THIS WILL RESULT IN THE
POTENTIAL FOR AREAS OF BLOWING/DRIFTING SNOW, ESPECIALLY AT RUT
AND MPV WHERE DURATION OF MODERATE SNOW WILL BE LONGEST. EXPECT
GUSTS TO SUBSIDE HEADING INTO TUESDAY EVENING.
OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY...
12Z WEDNESDAY THROUGH 12Z THURSDAY...MAINLY VFR CONDITIONS
EXPECTED AS RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
12Z THURSDAY THROUGH 00Z SATURDAY...TRENDING IFR/MVFR IN LIGHT
SNOW AS LOW PRESSURE MOVES EAST FROM THE OHIO VALLEY/GREAT LAKES
STATES.
00Z SATURDAY THROUGH 00Z SUNDAY...VFR CONDITIONS EXPECTING AS A
RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
&&
.EQUIPMENT...
AS OF 122 PM EST MONDAY...THE KTYX 88D DOPPLER RADAR LOCATED NEAR
WATERTOWN NEW YORK WILL BE DOWN AT LEAST THROUGH TUESDAY. THIS IS
DUE TO A PEDESTAL DYNAMIC FAULT. ELECTRONICS TECHNICIANS HAVE
ORDERED NEW PARTS TO FIX THIS PROBLEM. HOWEVER...THE NEW PARTS
HAVE NOT ARRIVED AS OF THIS TIME AND THE KTYX RADAR WILL LIKELY
NOT BE RESTORED TO SERVICE UNTIL SOMETIME THIS WEEK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER STORM WARNING UNTIL 1 AM EST WEDNESDAY FOR VTZ010>012-
019.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR VTZ004-
007>009-018.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/TABER
SHORT TERM...JMG
LONG TERM...KGM
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
656 AM EST TUE JAN 27 2015
.SYNOPSIS...
STRONG COASTAL LOW PRESSURE WILL SPREAD WIDESPREAD LIGHT TO
MODERATE SNOWS ACROSS THE EASTERN HALF OF THE FORECAST AREA TODAY
INTO EARLY THIS EVENING. HIGH PRESSURE RETURNS FOR LATER TONIGHT
THROUGH EARLY THURSDAY WITH SEASONABLY COLD AND MAINLY DRY
WEATHER. MORE LIGHT SNOWS ARE EXPECTED BY THURSDAY NIGHT INTO
FRIDAY AS LOW PRESSURE TRACKS EAST FROM THE GREAT LAKES STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 635 AM EST TUESDAY...FORECAST GENERALLY REMAINS ON TRACK
AND ONLY CHANGES AT 630 AM WERE TO MATCH CURRENT T/TD TRENDS
ACROSS THE AREA. I AM GROWING A BIT CONCERNED ON OUR SNOWFALL
TOTALS ON THE NORTHWESTERN EDGE OF THE PCPN SHIELD WITH LATEST
MODEL TRENDS CONTINUING TO SUGGEST DRY LOWER LEVELS WILL TEND TO
OVERCOME MID LEVEL DYNAMICS FOSTERING A GENERAL EROSION OF THE
WESTERN EDGE OF THE PCPN SHIELD ACROSS OUR AREA.
ADDITIONALLY...LOW LEVEL MOISTURE TRANSPORT TO THE NORTHWEST IS
APPEARING TO BE BLOCKED BY THE INTENSE MESOSCALE BAND ACROSS EC/SE
NEW ENGLAND. THIS IS NOT AN UNCOMMON OCCURRENCE...BUT DIFFICULT TO
PREDICT UNTIL IT DEVELOPS. WE`LL HAVE TO SEE HOW THINGS EVOLVE
OVER THE NEXT 3-5 HOURS BUT NO CHANGES AT THIS POINT. PRIOR
DISCUSSION FOLLOWS. HAVE A GREAT DAY.
PRIOR DISCUSSION FROM 321 AM EST TUESDAY...
INTENSE STORM CONTINUES TO DEVELOP OFF THE SOUTHEASTERN NEW
ENGLAND COAST NEAR NANTUCKET EARLY THIS MORNING WITH IMPRESSIVE
3-HOURLY PRESSURE FALLS NEAR 8 MB JUST NORTH OF THE 40N/-70W
BENCHMARK PER MOST RECENT MSAS ANALYSIS. A CLASSIC MILLER-B
EVOLUTION WITH INTENSE FRONTOGENETICAL BANDING FEATURES PIVOTING
SLOWLY NORTH AND WEST ACROSS ERN MA/CT/LI. THE DEVIL IS IN THE
DETAILS HOWEVER...ESPECIALLY IN REGARD TO TOTAL QPF/SNOWFALL
ACROSS OUR AREA. LATEST CAM OUTPUT INCLUDING THE RAP AND HRRR ALL
COMING ON BOARD WITH FAIRLY REALISTIC SOLUTIONS SHOWING WESTERN
EDGE OF STEADIER SNOWS WILL SLOWLY PIVOT NORTH AND WEST INTO VT
THROUGH THE COURSE OF THE MORNING/EARLY AFTERNOON WITH A RATHER
SHARP CUTOFF IN PCPN THE FURTHER NORTH AND WEST ONE PROGRESSES.
MOST PROBLEMATIC IS THE VERY COLD AND DRY ARCTIC AIRMASS IN PLACE
ACROSS OUR AREA. INDEED...LOW TO MID LEVEL DEWPOINTS REMAIN QUITE
LOW THIS MORNING AND THIS WILL TAKE SEVERAL HOURS OF MOISTENING
BEFORE STEADIER SNOWS REACH THE CENTRAL/NRN PORTIONS OF THE STATE.
REMAINING DRY IN NRN NY UNTIL LATE MORNING/EARLY AFTERNOON AND
MAINLY EASTERN PORTIONS OF CLINTON/ESSEX COUNTIES.
OLD RULE OF THUMB THAT USUALLY WORKS WELL HERE IS NOT TO GO TOO
EXTREME ON SNOWFALL TOTALS IF SOUTH COASTAL NEW ENGLAND IS BEARING
THE BRUNT OF THE STORM. RARELY TO WE SEE HEAVY SNOW SWATHS IN
EXCESS OF 200 MI AND THIS STORM WILL BE NO EXCEPTION. PAST
HISTORY ALSO SUGGESTS CLIPPER BOMBS GENERALLY UNDERPERFORM UP HERE
IN LIEU OF THE MORE CLASSIC GULF COAST/SOUTHEASTERN SEABOARD
SYSTEMS AS LONGITUDINAL DEVELOPMENT TYPICALLY OCCURS A BIT TOO FAR
EAST FOR US. IN ANY REGARD FELT THIS MORNINGS NAM HAD THE BEST
HANDLE ON CURRENT SITUATION AND USED ITS SOLUTION IN TANDEM WITH
BLENDED CAM QPF OUTPUT TO ARRIVE AT POP/SNOWFALL GRADIENTS ACROSS
OUR AREA. GFS IDEA BIASED ABOUT 50 MI TOO FAR SOUTH AND EAST AND
EURO QPF TOO SPREAD OUT WITH ITS COARSER RESOLUTION DESPITE A
FAIRLY ACCURATE DEPICTION OF LOW TO MID LEVEL FEATURES.
WHAT THIS ALL SPELLS IS A STEADY 5-10/6-12 INCH SNOWFALL FOR OUR
SOUTHERNMOST COUNTIES...WITH A FAIRLY QUICK DROP OFF IN SNOW
TOTALS NORTH AND WEST. A SW-NE ORIENTED BAND OF 3-7 INCHES STILL
PROGGED FROM ABOUT MIDDLEBURY NORTHEASTWARD THROUGH MONTPELIER AND
ST JOHNSBURY...AND A GENERAL 1-3 INCH SNOWFALL FROM ESSEX COUNTY
NY NORTHEAST INTO THE BURLINGTON/PLATTSBURGH VICINITY AND ST
ALBANS/FRANKLIN COUNTY. LITTLE IF ANY ACCUMULATION FROM A SARANAC
LAKE TO MALONE LINE WEST. THIS IS MORE OR LESS STAYING THE COURSE
AND WE`RE NOW INTO THE WAIT AND SEE TIMEFRAME TO SEE HOW THIS ALL
PANS OUT. ALL ADVISORIES/WARNINGS REMAIN IN PLACE WITH NO CHANGES
NEEDED AT THIS TIME.
BY TONIGHT OCCLUDED CYCLONE CONTINUES ITS TREK SLOWLY NORTHEAST
TOWARD YARMOUTH, NS WITH WESTERN EDGE OF PCPN GRADUALLY FADING AWAY
ACROSS OUR AREA AS DEEPER LIFT AND DYNAMICAL SUPPORT FOR PCPN WANE.
SOME LIGHT TAIL-END ACCUMULATIONS POSSIBLE NORTH AND
EAST...OTHERWISE TRENDING DRY OVERNIGHT. DID ADJUST LOW TEMPERATURES
A TAD MILDER THAN PREVIOUS FORECASTS GIVEN CONTINUED OVERCAST SKIES
AND NEAR NEUTRAL THERMAL ADVECTIVE PROCESSES...MAINLY POSITIVE
SINGLE DIGITS...LOCALLY A BIT COLDER FAR WEST WHERE SOME PARTIAL
CLEARING MAY OCCUR LATE.
&&
.SHORT TERM /WEDNESDAY/...
AS OF 321 AM EST TUESDAY...HIGH PRESSURE THEN BUILDS EAST INTO
THE REGION BY WEDNESDAY WITH SKIES TRENDING CLEAR TO PARTLY CLOUDY
THROUGH THE COURSE OF THE AFTERNOON. DRY WEATHER CONDITIONS
EXPECTED WITH BLENDED MOS NUMBERS SUPPORTING HIGH TEMPERATURES
GENERALLY IN THE TEENS...PERHAPS LOWER 20S FAR SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
AS OF 314 AM EST TUESDAY...DRY WEATHER TO START THE PERIOD AS
RIDGE OF HIGH PRESSURE AND ALOFT RESIDES OVER THE REGION WEDNESDAY
NIGHT. EARLY THURSDAY, THE RIDGE SLIDES EASTWARD WITH SOUTHERLY
FLOW DEVELOPING OVER THE REGION, INCREASING MOISTURE AND
MODERATING TEMPERATURES AHEAD OF A CLIPPER SYSTEM APPROACHING FROM
THE GREAT LAKES REGION. WHILE GFS AND ECMWF AGREE THAT
PRECIPITATION SHIELD WILL ENTER OUR WESTERN ZONES THURSDAY
AFTERNOON, THERE AREA DIFFERENCE REGARDING THE TRACK OF THE SFC
LOW AND THE PROGRESSION OF THE ASSOCIATED MID LEVEL TROUGH. THIS
LOW LOOKS TO BRING SNOW TO THE REGION THROUGH AT LEAST FRIDAY
EVENING. MID LEVEL TROUGH BECOMES NEGATIVELY TILTED ACCORDING TO
BOTH MODELS, THEREFORE AM FAVORING A SLOWER DEPARTURE OF
PRECIPITATION FROM NORTHEASTERN VERMONT AS DEPICTED BY THE ECMWF.
EXPECTING SOME LINGERING POPS INTO EARLY SATURDAY MORNING, BUT
NORTH/NORTHWEST FLOW BEHIND THIS SYSTEM WILL BRING IN DRIER AIR.
SO EXPECT SATURDAY TO BE MOSTLY DRY AT THIS POINT. AT THIS POINT,
EXPECT POTENTIAL SNOWFALL TOTALS TO RANGE FROM 2 TO 5 INCHES.
ANOTHER SYSTEM DEVELOPING IN THE MISSISSIPPI VALLEY WILL MOVE
NORTHEASTWARD LATE SUNDAY INTO MONDAY...BRINGING ANOTHER CHANCE
FOR SNOW FOR THE BEGINNING OF NEXT WEEK.
TEMPERATURES WEDNESDAY NIGHT WILL BE GENERALLY IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO. TEMPERATURES MODERATING IN THE
SOUTHERLY FLOW THURSDAY THROUGH FRIDAY WITH MAXES IN THE 20S AND
MINS IN THE TEENS TO L20S. BEHIND THE CLIPPER LOW, COLD AIR WILL
RETURN WITH MINS OF -15F TO ZERO FOR THE REST OF THE PERIOD. MAXES
WILL REACH SINGLE DIGITS TO MID TEENS SATURDAY THROUGH MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
THROUGH 12Z WEDNESDAY...VFR CONDITIONS WILL DETERIORATE TO MVFR
AS SNOW SPREADS NORTHWESTWARD THIS MORNING. EXPECT MVFR
CONDITIONS AND SNOW TO MOVE INTO KRUT BETWEEN 12-15Z...KMPV 13-
15Z...KBTV/KPBG 15Z-17Z...AND KSLK 16Z-18Z. KMSS WILL BE FAR
ENOUGH NORTH AND WEST TO REMAIN VFR. SOME EMBEDDED MODERATE SNOW
IS POSSIBLE WITH IFR/LIFR CONDITIONS AFFECTING KRUT/KMPV 14Z-
22Z...KBTV/KPBG 17Z-21Z AND KSLK 18Z-23Z.
SNOW WILL LIGHTEN AND DIMINISH THIS EVENING WITH MOSTLY DRY
CONDITIONS SETTLING IN AFTER MIDNIGHT/05Z. EXPECT CONDITIONS TO
IMPROVE TO MVFR/VFR AS SNOWFALL COMES TO AN END.
NORTH TO NORTHEAST WINDS OF 6-12KTS WILL INCREASE AND BECOME
GUSTY AROUND 25KTS BY MID MORNING. THIS WILL RESULT IN THE
POTENTIAL FOR AREAS OF BLOWING/DRIFTING SNOW, ESPECIALLY AT RUT
AND MPV WHERE DURATION OF MODERATE SNOW WILL BE LONGEST. EXPECT
GUSTS TO SUBSIDE HEADING INTO TUESDAY EVENING.
OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY...
12Z WEDNESDAY THROUGH 12Z THURSDAY...MAINLY VFR CONDITIONS
EXPECTED AS RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
12Z THURSDAY THROUGH 00Z SATURDAY...TRENDING IFR/MVFR IN LIGHT
SNOW AS LOW PRESSURE MOVES EAST FROM THE OHIO VALLEY/GREAT LAKES
STATES.
00Z SATURDAY THROUGH 00Z SUNDAY...VFR CONDITIONS EXPECTING AS A
RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
&&
.EQUIPMENT...
AS OF 122 PM EST MONDAY...THE KTYX 88D DOPPLER RADAR LOCATED NEAR
WATERTOWN NEW YORK WILL BE DOWN AT LEAST THROUGH TUESDAY. THIS IS
DUE TO A PEDESTAL DYNAMIC FAULT. ELECTRONICS TECHNICIANS HAVE
ORDERED NEW PARTS TO FIX THIS PROBLEM. HOWEVER...THE NEW PARTS
HAVE NOT ARRIVED AS OF THIS TIME AND THE KTYX RADAR WILL LIKELY
NOT BE RESTORED TO SERVICE UNTIL SOMETIME THIS WEEK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER STORM WARNING UNTIL 1 AM EST WEDNESDAY FOR VTZ010>012-
019.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR VTZ004-
007>009-018.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...KGM
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
635 AM EST TUE JAN 27 2015
.SYNOPSIS...
STRONG COASTAL LOW PRESSURE WILL SPREAD WIDESPREAD LIGHT TO
MODERATE SNOWS ACROSS THE EASTERN HALF OF THE FORECAST AREA TODAY
INTO EARLY THIS EVENING. HIGH PRESSURE RETURNS FOR LATER TONIGHT
THROUGH EARLY THURSDAY WITH SEASONABLY COLD AND MAINLY DRY
WEATHER. MORE LIGHT SNOWS ARE EXPECTED BY THURSDAY NIGHT INTO
FRIDAY AS LOW PRESSURE TRACKS EAST FROM THE GREAT LAKES STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 635 AM EST TUESDAY...FORECAST GENERALLY REMAINS ON TRACK
AND ONLY CHANGES AT 630 AM WERE TO MATCH CURRENT T/TD TRENDS
ACROSS THE AREA. I AM GROWING A BIT CONCERNED ON OUR SNOWFALL
TOTALS ON THE NORTHWESTERN EDGE OF THE PCPN SHIELD WITH LATEST
MODEL TRENDS CONTINUING TO SUGGEST DRY LOWER LEVELS WILL TEND TO
OVERCOME MID LEVEL DYNAMICS FOSTERING A GENERAL EROSION OF THE
WESTERN EDGE OF THE PCPN SHIELD ACROSS OUR AREA.
ADDITIONALLY...LOW LEVEL MOISTURE TRANSPORT TO THE NORTHWEST IS
APPEARING TO BE BLOCKED BY THE INTENSE MESOSCALE BAND ACROSS EC/SE
NEW ENGLAND. THIS IS NOT AN UNCOMMON OCCURRENCE...BUT DIFFICULT TO
PREDICT UNTIL IT DEVELOPS. WE`LL HAVE TO SEE HOW THINGS EVOLVE
OVER THE NEXT 3-5 HOURS BUT NO CHANGES AT THIS POINT. PRIOR
DISCUSSION FOLLOWS. HAVE A GREAT DAY.
PRIOR DISCUSSION FROM 321 AM EST TUESDAY...
INTENSE STORM CONTINUES TO DEVELOP OFF THE SOUTHEASTERN NEW
ENGLAND COAST NEAR NANTUCKET EARLY THIS MORNING WITH IMPRESSIVE
3-HOURLY PRESSURE FALLS NEAR 8 MB JUST NORTH OF THE 40N/-70W
BENCHMARK PER MOST RECENT MSAS ANALYSIS. A CLASSIC MILLER-B
EVOLUTION WITH INTENSE FRONTOGENETICAL BANDING FEATURES PIVOTING
SLOWLY NORTH AND WEST ACROSS ERN MA/CT/LI. THE DEVIL IS IN THE
DETAILS HOWEVER...ESPECIALLY IN REGARD TO TOTAL QPF/SNOWFALL
ACROSS OUR AREA. LATEST CAM OUTPUT INCLUDING THE RAP AND HRRR ALL
COMING ON BOARD WITH FAIRLY REALISTIC SOLUTIONS SHOWING WESTERN
EDGE OF STEADIER SNOWS WILL SLOWLY PIVOT NORTH AND WEST INTO VT
THROUGH THE COURSE OF THE MORNING/EARLY AFTERNOON WITH A RATHER
SHARP CUTOFF IN PCPN THE FURTHER NORTH AND WEST ONE PROGRESSES.
MOST PROBLEMATIC IS THE VERY COLD AND DRY ARCTIC AIRMASS IN PLACE
ACROSS OUR AREA. INDEED...LOW TO MID LEVEL DEWPOINTS REMAIN QUITE
LOW THIS MORNING AND THIS WILL TAKE SEVERAL HOURS OF MOISTENING
BEFORE STEADIER SNOWS REACH THE CENTRAL/NRN PORTIONS OF THE STATE.
REMAING DRY IN NRN NY UNTIL LATE MORNING/EARLY AFTERNOON AND
MAINLY EASTERN PORTIONS OF CLINTON/ESSEX COUNTIES.
OLD RULE OF THUMB THAT USUALLY WORKS WELL HERE IS NOT TO GO TOO
EXTREME ON SNOWFALL TOTALS IF SOUTH COASTAL NEW ENGLAND IS BEARING
THE BRUNT OF THE STORM. RARELY TO WE SEE HEAVY SNOW SWATHS IN
EXCESS OF 200 MI AND THIS STORM WILL BE NO EXCEPTION. PAST
HISTORY ALSO SUGGESTS CLIPPER BOMBS GENERALLY UNDERPERFORM UP HERE
IN LIEU OF THE MORE CLASSIC GULF COAST/SOUTHEASTERN SEABOARD
SYSTEMS AS LONGITUDINAL DEVELOPMENT TYPICALLY OCCURS A BIT TOO FAR
EAST FOR US. IN ANY REGARD FELT THIS MORNINGS NAM HAD THE BEST
HANDLE ON CURRENT SITUATION AND USED ITS SOLUTION IN TANDEM WITH
BLENDED CAM QPF OUTPUT TO ARRIVE AT POP/SNOWFALL GRADIENTS ACROSS
OUR AREA. GFS IDEA BIASED ABOUT 50 MI TOO FAR SOUTH AND EAST AND
EURO QPF TOO SPREAD OUT WITH ITS COARSER RESOLUTION DESPITE A
FAIRLY ACCURATE DEPICTION OF LOW TO MID LEVEL FEATURES.
WHAT THIS ALL SPELLS IS A STEADY 5-10/6-12 INCH SNOWFALL FOR OUR
SOUTHERNMOST COUNTIES...WITH A FAIRLY QUICK DROP OFF IN SNOW
TOTALS NORTH AND WEST. A SW-NE ORIENTED BAND OF 3-7 INCHES STILL
PROGGED FROM ABOUT MIDDLEBURY NORTHEASTWARD THROUGH MONTPELIER AND
ST JOHNSBURY...AND A GENERAL 1-3 INCH SNOWFALL FROM ESSEX COUNTY
NY NORTHEAST INTO THE BURLINGTON/PLATTSBURGH VICINITY AND ST
ALBANS/FRANKLIN COUNTY. LITTLE IF ANY ACCUMULATION FROM A SARANAC
LAKE TO MALONE LINE WEST. THIS IS MORE OR LESS STAYING THE COURSE
AND WE`RE NOW INTO THE WAIT AND SEE TIMEFRAME TO SEE HOW THIS ALL
PANS OUT. ALL ADVISORIES/WARNINGS REMAIN IN PLACE WITH NO CHANGES
NEEDED AT THIS TIME.
BY TONIGHT OCCLUDED CYCLONE CONTINUES ITS TREK SLOWLY NORTHEAST
TOWARD YARMOUTH, NS WITH WESTERN EDGE OF PCPN GRADUALLY FADING AWAY
ACROSS OUR AREA AS DEEPER LIFT AND DYNAMICAL SUPPORT FOR PCPN WANE.
SOME LIGHT TAIL-END ACCUMULATIONS POSSIBLE NORTH AND
EAST...OTHERWISE TRENDING DRY OVERNIGHT. DID ADJUST LOW TEMPERATURES
A TAD MILDER THAN PREVIOUS FORECASTS GIVEN CONTINUED OVERCAST SKIES
AND NEAR NEUTRAL THERMAL ADVECTIVE PROCESSES...MAINLY POSITIVE
SINGLE DIGITS...LOCALLY A BIT COLDER FAR WEST WHERE SOME PARTIAL
CLEARING MAY OCCUR LATE.
&&
.SHORT TERM /WEDNESDAY/...
AS OF 321 AM EST TUESDAY...HIGH PRESSURE THEN BUILDS EAST INTO
THE REGION BY WEDNESDAY WITH SKIES TRENDING CLEAR TO PARTLY CLOUDY
THROUGH THE COURSE OF THE AFTERNOON. DRY WEATHER CONDITIONS
EXPECTED WITH BLENDED MOS NUMBERS SUPPORTING HIGH TEMPERATURES
GENERALLY IN THE TEENS...PERHAPS LOWER 20S FAR SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
AS OF 314 AM EST TUESDAY...DRY WEATHER TO START THE PERIOD AS
RIDGE OF HIGH PRESSURE AND ALOFT RESIDES OVER THE REGION WEDNESDAY
NIGHT. EARLY THURSDAY, THE RIDGE SLIDES EASTWARD WITH SOUTHERLY
FLOW DEVELOPING OVER THE REGION, INCREASING MOISTURE AND
MODERATING TEMPERATURES AHEAD OF A CLIPPER SYSTEM APPROACHING FROM
THE GREAT LAKES REGION. WHILE GFS AND ECMWF AGREE THAT
PRECIPITATION SHIELD WILL ENTER OUR WESTERN ZONES THURSDAY
AFTERNOON, THERE AREA DIFFERENCE REGARDING THE TRACK OF THE SFC
LOW AND THE PROGRESSION OF THE ASSOCIATED MID LEVEL TROUGH. THIS
LOW LOOKS TO BRING SNOW TO THE REGION THROUGH AT LEAST FRIDAY
EVENING. MID LEVEL TROUGH BECOMES NEGATIVELY TILTED ACCORDING TO
BOTH MODELS, THEREFORE AM FAVORING A SLOWER DEPARTURE OF
PRECIPITATION FROM NORTHEASTERN VERMONT AS DEPICTED BY THE ECMWF.
EXPECTING SOME LINGERING POPS INTO EARLY SATURDAY MORNING, BUT
NORTH/NORTHWEST FLOW BEHIND THIS SYSTEM WILL BRING IN DRIER AIR.
SO EXPECT SATURDAY TO BE MOSTLY DRY AT THIS POINT. AT THIS POINT,
EXPECT POTENTIAL SNOWFALL TOTALS TO RANGE FROM 2 TO 5 INCHES.
ANOTHER SYSTEM DEVELOPING IN THE MISSISSIPPI VALLEY WILL MOVE
NORTHEASTWARD LATE SUNDAY INTO MONDAY...BRINGING ANOTHER CHANCE
FOR SNOW FOR THE BEGINNING OF NEXT WEEK.
TEMPERATURES WEDNESDAY NIGHT WILL BE GENERALLY IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO. TEMPERATURES MODERATING IN THE
SOUTHERLY FLOW THURSDAY THROUGH FRIDAY WITH MAXES IN THE 20S AND
MINS IN THE TEENS TO L20S. BEHIND THE CLIPPER LOW, COLD AIR WILL
RETURN WITH MINS OF -15F TO ZERO FOR THE REST OF THE PERIOD. MAXES
WILL REACH SINGLE DIGITS TO MID TEENS SATURDAY THROUGH MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
THROUGH 06Z WEDNESDAY...VFR CONDITIONS PERSIST FOR THE NEXT
COUPLE HOURS, WITH MVFR CIGS/VSBYS SPREADING NORTHWESTWARD
ASSOCIATED WITH APPROACHING SNOW. LOW-LEVEL DRY AIR FROM NORTHERLY
ARCTIC AIR HAS SLOWED PROGRESSION OF SNOW AND DETERIORATING
CONDITIONS. EXPECT MVFR CONDITIONS TO MOVE INTO KRUT BETWEEN 09Z-
11Z...KMPV 11Z- 14Z...KBTV/KPBG 15Z-17Z...AND KSLK 16Z-18Z. KMSS
WILL BE FAR ENOUGH NORTH AND WEST TO REMAIN VFR.
HEAVIER SNOW WITH IFR-LIFR CONDITIONS WILL MOVE INTO THE
REGION...FOLLOWING THE SAME TRENDS AS ONSET OF SNOW APPROXIMATELY
2-4 HOURS AFTER THE ONSET OF SNOW. EXPECT THIS BAND OF MODERATE
SNOWFALL TO WEAKEN IN THE MID AFTERNOON, AROUND 20-22Z. AS
SNOWFALL LIGHTENS, CONDITIONS WILL IMPROVE TO MVFR/VFR.
WINDS WILL BE NORTH TO NORTHEAST AROUND 6-12 KTS THIS MORNING,
INCREASING AND BECOMING GUSTY (UP TO 25 KTS) INTO MID TO LATE
MORNING. POTENTIAL FOR AREAS OF BLOWING/DRIFTING SNOW, ESPECIALLY
AT RUT AND MPV WHERE DURATION OF MODERATE SNOW WILL BE LONGEST.
EXPECT GUSTS TO SUBSIDE HEADING INTO TUESDAY EVENING.
OUTLOOK 06Z WEDNESDAY THROUGH SATURDAY...
06Z THROUGH 12Z WEDNESDAY...MAINLY MVFR IN SNOW FROM DEEPENING
STORM OFF THE NEW ENGLAND COAST...ESPECIALLY VERMONT TERMINALS AND
KPBG. KMSS LIKELY TO REMAIN PCPN FREE MUCH OF THE PERIOD WITH
CONTINUED VFR CONDS. GUSTY NORTH WINDS TO 25 KTS
POSSIBLE...ESPECIALLY AT KPBG/KBTV WHERE NORTHERLY CHANNELING
EFFECTS MAY OCCUR.
12Z WEDNESDAY THROUGH 12Z THURSDAY...MAINLY VFR CONDITIONS
EXPECTED AS RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
12Z THURSDAY THROUGH 00Z SATURDAY...TRENDING IFR/MVFR IN LIGHT
SNOW AS LOW PRESSURE MOVES EAST FROM THE OHIO VALLEY/GREAT LAKES
STATES.
00Z SATURDAY THROUGH 00Z SUNDAY...VFR CONDITIONS EXPECTING AS A
RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
&&
.EQUIPMENT...
AS OF 122 PM EST MONDAY...THE KTYX 88D DOPPLER RADAR LOCATED NEAR
WATERTOWN NEW YORK WILL BE DOWN AT LEAST THROUGH TUESDAY. THIS IS
DUE TO A PEDESTAL DYNAMIC FAULT. ELECTRONICS TECHNICIANS HAVE
ORDERED NEW PARTS TO FIX THIS PROBLEM. HOWEVER...THE NEW PARTS
HAVE NOT ARRIVED AS OF THIS TIME AND THE KTYX RADAR WILL LIKELY
NOT BE RESTORED TO SERVICE UNTIL SOMETIME THIS WEEK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER STORM WARNING UNTIL 1 AM EST WEDNESDAY FOR VTZ010>012-
019.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR VTZ004-
007>009-018.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...KGM
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS RALEIGH NC
645 AM EST TUE JAN 27 2015
.SYNOPSIS...STRONG LOW PRESSURE OFF NEW ENGLAND THIS MORNING WILL
LIFT NORTHEAST AWAY FROM OUR AREA TODAY. HIGH PRESSURE WILL BUILD IN
FROM THE NORTHWEST THIS AFTERNOON THROUGH EARLY THURSDAY. ANOTHER
CLIPPER LOW PRESSURE SYSTEM WILL SWING BY JUST TO OUR NORTH LATE
THURSDAY THROUGH THURSDAY NIGHT... THEN HIGH PRESSURE WILL AGAIN
BUILD INTO OUR AREA FROM THE NORTHWEST ON FRIDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
AS OF 240 AM TUESDAY...
TODAY AND TONIGHT: FRONTAL SYSTEM IS CURRENTLY MOVING THROUGH THE
AREA AS LOW PRESSURE CONTINUES TO DEEPEN ACROSS THE DELMARVA. THE
CWA IS CURRENTLY SPLIT BETWEEN DRIER AIR TO THE WEST OF ROUTE 1 AND
MORE MOISTURE TO THE EAST. A BAND OF PRECIPITATION HAS SET UP ALONG
WHAT APPEARS TO BE THE FRONTAL BOUNDARY AND HAS BROUGHT SOME
SCATTERED REPORTS OF A RAIN/SNOW MIX FROM PERSON COUNTY DOWN THROUGH
WAKE COUNTY WITH MOSTLY RAIN OR DRIZZLE SOUTH OF THERE. THIS BAND
WILL MOVE GRADUALLY EASTWARD THROUGH THE EARLY MORNING HOURS TOWARDS
TEH I-95 CORRIDOR AND THE EASTERN TIER OF COUNTIES. SCATTERED
REPORTS OF LIGHT SNOW OR RAIN WILL CONTINUE THROUGH THE MORNING
BEFORE MOST LOCALES DRY OUT. THE THREAT FOR SNOW SHOULD END AFTER
12Z AS RAP FORECAST SOUNDINGS INDICATE SIGNIFICANT DRYING IN THE
SNOW GROWTH ZONE. NO ACCUMULATION IS EXPECTED OR ANY IMPACTS FROM
THE SNOW ASIDE FROM A POTENTIAL DUSTING ON ELEVATED SURFACES AT BEST
AS SOIL TEMPERATURES ARE STILL NEAR 40 DEGREES.
THIS SETUP HAS ALSO CAUSED A SPLIT IN CLOUD COVER WITH AREAS UNDER
AND EAST OF THE PRECIPITATION BAND EXPERIENCING MAINLY MVFR CEILINGS
WITH VFR CONDITIONS BACK TO THE WEST. A FEW WIND GUSTS STILL OUT
THERE UP TO 20 KTS OR SO OUT OF THE NORTHWEST. GUSTS MAY DIE OFF
TOWARDS SUNRISE BUT WILL PICK UP AGAIN LATER THIS AFTERNOON.
TEMPERATURES THIS AFTERNOON IN THE LOW TO MID 40S NE TO SW AS CLOUDS
LINGER LONGER AND COLD AIR ADVECTION IS MORE PRONOUNCED IN THE
NORTHEAST. EXPECT DRYING TO CONTINUE INTO TONIGHT WITH CLEARING
SKIES BUT WINDS REMAINING 5-10 KTS SO NOT EXACTLY GREAT FOR
RADIATIONAL COOLING BUT TEMPS WILL STILL MANAGE TO DROP INTO THE
MIDDLE 20S WITH THE CHANGE IN AIRMASS.
WEDNESDAY AND WEDNESDAY NIGHT: A DRY DAY EXPECTED FOR WEDNESDAY AS
CENTRAL NC IS SANDWICHED BETWEEN THE EXITING BLIZZARD TO THE
NORTHEAST AND INCOMING HIGH PRESSURE TO THE NORTHWEST. SURFACE
PRESSURE GRADIENT WILL RELAX A LITTLE BUT STILL A GOOD COLD AIR
ADVECTION REGIME BOTH AT THE SURFACE AND ALOFT ON THE BACK SIDE OF
THE UPPER LEVEL TROUGH. THIS WILL KEEP TEMPS DOWN IN THE LOW TO MID
40S...ABOUT 10 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. WINDS 5-
10 KTS OUT OF THE NORTH VEERING TO NORTHEASTERLY LATER IN THE DAY.
CLOUDS WILL GRADUALLY INCREASE IN THE NORTHWEST ON WEDNESDAY NIGHT
AS THE NEXT LOW PRESSURE SYSTEM MOVES INTO THE OHIO VALLEY. THIS
WILL HELP TO KEEP LOW TEMPERATURES UP IN THE TRIAD. GENERALLY MID
20S BUT POSSIBLY SOME LOWER 20S IN OUR EASTERN NORMALLY COLD ZONES.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 200 AM TUESDAY...
THU/THU NIGHT: THE GREAT LAKES SHORTWAVE TROUGH WILL TRACK ESE THEN
EASTWARD ACROSS THE NORTHEAST/MIDATLANTIC STATES... TRACKING THROUGH
THE BASE OF THE POLAR LOW OVER HUDSON BAY... WHILE ITS CORRESPONDING
SURFACE LOW CROSSES THE OH VALLEY AND MIDATLANTIC COAST. AFTER A
CHILLY MORNING WITH THE SURFACE RIDGE OVERHEAD... INCREASING
SOUTHERLY LOW LEVEL FLOW AS THE HIGH SHIFTS SSE WILL ALLOW FOR A
MODEST RECOVERY IN THICKNESSES... BUT STILL BELOW NORMAL... AND THE
TEMP RISE WILL BE HINDERED BY THICKENING AND LOWERING CLOUDS WITH
APPROACHING WEAK MID LEVEL DPVA AND LOW LEVEL FRONTAL ZONE. BUT
MODELS STILL SHOW PW VALUES JUST BARELY REACHING ABOVE NORMAL... AND
GFS/NAM BUFR FORECAST SOUNDINGS SHOW A DRY SUBCLOUD LAYER BELOW 850
MB THROUGH THU. MODEL QPF IS ALSO SCANT WITH THE GFS/NAM/SREF MEAN
STAYING DRY OVER CENTRAL NC THROUGH THU NIGHT. AFTER 00Z THE COLUMN
STARTS TO DRY OUT ALOFT BEHIND THE 700 MB TROUGH... AND JUST AHEAD
OF THE SURFACE FRONT WHICH IS EXPECTED TO SWEEP EAST THROUGH CENTRAL
NC AFTER MIDNIGHT. WILL TRIM BACK EXISTING SLIGHT CHANCE POPS A
BIT... FOCUSING THEM LATE THU AFTERNOON UNTIL SHORTLY AFTER
MIDNIGHT... HOWEVER AM RELUCTANT TO REMOVE THEM ENTIRELY AS THE
ECMWF CONTINUES TO GENERATE LIGHT PRECIP LATE THU AFTERNOON AND THU
EVENING. EXPECT HIGHS THU IN THE MID 40S TO AROUND 50. LOWS THU
NIGHT 32-38.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 200 AM TUESDAY...
FRI-SAT: THE MID LEVEL TROUGH AXIS WILL BE SWINGING TO OUR EAST FRI
MORNING WITH THE SURFACE COLD FRONT PUSHING OFF THE NC COAST. NW LOW
LEVEL FLOW WILL BRING IN COOLER AIR AS HIGH PRESSURE INITIALLY
CENTERED OVER NRN MINN DRIFTS SOUTHEAST... BUILDING INTO AND OVER
THE MIDATLANTIC THROUGH VA/ERN NC THROUGH SAT. SHOULD SEE MOSTLY
CLEAR SKIES FRI/FRI NIGHT... FOLLOWED BY INCREASING HIGH THIN CLOUDS
SAT AS WE START TO SEE INITIAL ENERGY EJECTING FROM THE DESERT SW
LOW TRACK EASTWARD WITHIN CONFLUENT NW MID LEVEL FLOW. WITH FALLING
THICKNESSES FRI... EXPECT BELOW-NORMAL HIGHS IN THE MID 40S TO LOWER
50S. LOWS FRI NIGHT IN THE MID 20S... THEN WITH SUCH A CHILLY START
AND THE CANADIAN-SOURCE AIR MASS BUILDING IN YIELDING THICKNESSES AT
LEAST 30 M BELOW NORMAL... HIGHS SAT SHOULD ONLY BE IN THE 40-45
RANGE.
SAT NGT-MON: A LOT OF UNCERTAINTY IN THE DETAILS PERSISTS THIS
MORNING... HOWEVER IT`S LOOKING MORE LIKELY THAT WE`RE ENTERING INTO
A PERIOD OF MORE ACTIVE WEATHER DOMINATED BY SOUTHERN STREAM ENERGY
BUT WITH POTENTIAL INJECTIONS OF COOLER AIR FROM THE NORTHERN
STREAM. A NRN STREAM WAVE DROPPING SOUTHEAST FROM MT THROUGH THE
CENTRAL PLAINS WILL MERGE WITH SOUTHERN STREAM ENERGY EMANATING FROM
THE LOW OVER NRN MEX SAT NIGHT/SUN... BRINGING MID LEVEL DPVA INTO
NC SUN/SUN NIGHT. THE SHIFTING OF THE SURFACE HIGH ESE OFF THE COAST
WILL ALLOW A MOIST RETURN FLOW OFF THE GULF INTO THE GULF/MIDSOUTH
AND SOUTHEAST STATES... AS SURFACE LOW PRESSURE DEVELOPS ALONG THE
BAROCLINIC ZONE NEAR THE NW GULF COAST AND TRACKS NORTHEAST TOWARD
NC. THE GFS/ECMWF BRING PRECIP INTO WRN NC BY MIDDAY SUN... THEN
SPREAD IT EASTWARD THROUGH CENTRAL NC SUN NIGHT INTO EARLY MON
MORNING. BOTH THE GFS/ECMWF SHOW A MILLER TYPE-B CYCLOGENESIS
PATTERN BUT WITH VARIED LOW PLACEMENT... WITH THE ECMWF DEPICTING A
FURTHER-SOUTH TRIPLE POINT LOW TRACK VERSUS THE GFS. THE LATEST RUNS
SHOWS SUFFICIENTLY WARM LOW- AND MID-LEVEL THICKNESSES TO SUPPORT AN
ALL-RAIN EVENT... BUT GIVEN THIS PATTERN... WILL NEED TO WATCH MODEL
TRENDS CAREFULLY IN THE COMING DAYS. WITH OTHERWISE GOOD MODEL
AGREEMENT ON TIMING AND THE MID-LEVEL PATTERN... WILL BUMP UP
POPS... FOCUSING THE HIGHER CHANCES SUN AFTERNOON THROUGH SUN
NIGHT... TAPERING DOWN WEST-TO-EAST MON MORNING AS THE DAMPENING MID
LEVEL SHORTWAVE TROUGH SHIFTS EAST OVER THE MIDATLANTIC/ NORTHEAST
WITH SURFACE FRONTAL PASSAGE THROUGH NC. EXPECT IMPROVING WEATHER
LATE MON WITH ANOTHER CANADIAN HIGH CENTERED OVER THE MIDWEST
BUILDING INTO OUR AREA. EXPECT BELOW NORMAL TEMPS THROUGH SUN
NIGHT... WITH MORE UNCERTAINTY FOR HIGHS ON MON AS MUCH WILL DEPEND
ON WHETHER OR NOT WE GET INTO THE WARM SECTOR BEFORE FRONTAL
PASSAGE. WILL KEEP TEMPS BELOW NORMAL FOR NOW BUT IF MODEL WARMING
TRENDS HOLD... MAY NEED TO BUMP UP MON HIGHS QUITE A BIT IN LATER
FORECASTS. -GIH
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 645 AM TUESDAY...
24 HOUR TAF PERIOD: LIGHT SNOW OVERSPREADING NORTHEASTERN AREAS OF
THE CWA THIS MORNING. SNOW IS CURRENTLY MOVING OUT OF THE KRWI AREA
AND IS NOW CONFINED NORTH AND EAST. ELSEWHERE PRECIPITATION HAS
LARGELY ENDED OUTSIDE OF A FEW SNOW FLURRIES. WINDS ARE LIGHT AND
VARIABLE AT THIS HOUR BUT WILL BE PICKING BACK UP TO 5-10 KTS OUT OF
THE NORTHWEST THIS MORNING AND THEN GUSTING TO 20 KTS THIS
AFTERNOON. SOME MVFR CEILINGS STILL IN PLACE IN AREAS WHERE LIGHT
SNOW IS STILL FALLING. ELSEWHERE VFR CEILINGS ARE PREVAILING AND
SKIES WILL CONTINUE TO CLEAR AS THE DAY PROGRESSES WITH THE
EXCEPTION OF THE NORTHEASTERN AREAS WHERE CLOUDS WILL LINGER.
LONG TERM: THE NEXT THREAT TO AVIATION CONDITIONS WILL BE THURSDAY
NIGHT INTO FRIDAY MORNING AS A FRONTAL SYSTEM CROSSES THE AREA AND
THEN ANOTHER SYSTEM SUNDAY INTO MONDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...ELLIS
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
508 AM CST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 257 AM CST TUE JAN 27 2015
ONLY AREA OF STRATUS VERY EARLY THIS MORNING IS SITUATED THROUGH
PORTIONS OF SOUTHWESTERN MINNESOTA INTO THE IOWA GREAT LAKES
AREA...WITH SOME PATCHY FOG LOCATED WITHIN THIS NARROW BAND. BOTH
THE RAP AND SREF ARE HANDLING THESE LOW CLOUDS/REDUCED VISIBILITY
WELL...AND HAVE IT DISSIPATING BY 15Z. OTHERWISE...THE REMAINDER OF
THE CWA REMAINS FOG FREE THIS MORNING SO REMOVED MOST OF THE FOG
FROM THE FORECAST. HIGH PRESSURE SITUATED ACROSS THE REGION THIS
MORNING WILL PUSH OFF TO THE EAST THROUGH THE DAY...AND AS IT DOES
SO THE LOW LEVEL FLOW WILL BECOME SOUTHEASTERLY. THIS AND A
STRENGTHENING INVERSION WILL INHIBIT MIXING TODAY...ESPECIALLY IN
THE EAST...AND IN RESPONSE HIGH TEMPERATURES WILL GENERALLY BE
COOLER THAN YESTERDAY. STILL VERY MILD FOR THIS TIME OF YEAR
HOWEVER...TOPPING OUT IN THE LOWER 40S THROUGH SOUTHWESTERN
MINNESOTA INTO THE EASTERN PORTIONS OF OUR IOWA ZONES...TO 50S
THROUGH THE JAMES RIVER VALLEY THROUGH THE LOWER MISSOURI RIVER
CORRIDOR.
A SURFACE TROUGH BEGINS TO APPROACH FROM THE WEST TONIGHT...AND IT
WILL BE A MILDER NIGHT WITH INCREASING WARM AIR ADVECTION OUT AHEAD
OF THE SYSTEM. WITH THAT...LOOKING AT LOWS GENERALLY LOWER TO MID
30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 257 AM CST TUE JAN 27 2015
WEDNESDAY STILL TO BE THE FINAL VERY MILD DAY AS LOW PRESSURE PASSES
AND COOLER AIR BEGINS TO DRAIN SOUTHWARD. MODELS SIMILAR TO
YESTERDAY SO NO REAL CHANGES. STILL MAINTAIN A SMALL CHANCE FOR
LIGHT SNOW IN THE NORTH AS A WAVE PASSES BY BUT A BIT MOISTURE
STARVED SO NOT ANTICIPATING MUCH OF ANYTHING.
BECOMING A BIT WINDY LATE WEDNESDAY AFTERNOON AND NIGHT AS COLD AIR
ADVECTION AND A STRONG PRESSURE GRADIENT WORK TO MIX DOWN SOME
STRONG WINDS ALOFT. LIKELY SEE SOME WIND GUSTS OF 35 MPH OR SO
WEDNESDAY NIGHT. WITH SOME CLOUD COVER AND WIND TEMPERATURES SHOULD
STAY FAIRLY MILD FOR THIS TIME OF YEAR WITH THURSDAY MORNING LOWS
FROM THE MID 20S TO LOWER 30S.
THURSDAY STILL A BIT BREEZY AND DEFINITELY COLDER. THE LOWER LEVEL
THERMAL FIELD HAS COME IN A BIT COLDER THIS TIME AROUND WHICH IS
ALSO FAIRLY WELL AGREED UPON SO WENT AHEAD AND LOWERED HIGHS A
COUPLE OF DEGREES. HIGHS MAINLY UPPER 20S TO MID 30S.
IN THE OUTER PERIODS (FRIDAY THROUGH MONDAY)...THE COLDER PATTERN
SETTLES IN AND REMAINS IN PLACE. MODELS ALL IN PRETTY GOOD AGREEMENT
THIS TIME AROUND SO WILL KEEP TEMPERATURES ON THE COLDER SIDE OF
GUIDANCE. FRIDAY IS THE LAST OF THE MILD DAYS AS SOUTHERLY FLOW
KEEPS 925MB TEMPERATURES CLOSER TO ZERO. SATURDAY LIKELY POSING THE
POTENTIAL FOR THE BIGGEST ERROR IN FORECASTING AS THE ARCTIC
BOUNDARY IS PROGGED TO MOVE THROUGH. A LITTLE FASTER AND HIGHS WILL
BE IN THE 20S...A LITTLE SLOWER AND HIGH WOULD BE IN THE 40S SO
UPPER 20S IN THE NORTH AND MID 30S IN THE SOUTH SEEMS LIKE A GOOD
HEDGE TOWARDS THIS FAIRLY SHARP THERMAL GRADIENT. WILL ALSO HAVE A
CHANCE FOR LIGHT SNOW ON SATURDAY AND SATURDAY NIGHT AS THIS COLD
AIR SURGES SOUTH. SUNDAY AND MONDAY WELL INTO THE COLD AIR SO JUST
LOOKING AT HIGHS IN THE TEENS TO LOWER 20S AND LOWS IN THE SINGLE
DIGITS TO LOWER TEENS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 505 AM CST TUE JAN 27 2015
WILL HAVE AREAS OF LIFR TO MVFR CIGS/VISBYS EAST OF INTERSTATE 29
THROUGH 15Z. OTHERWISE...VFR CONDITIONS THROUGH THE TAF PERIOD.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JM
LONG TERM...08
AVIATION...JM
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
521 AM CST TUE JAN 27 2015
.UPDATE...ADDED AVIATION SECTION FOR 12Z TAF`S.
&&
.AVIATION...BNA/CKV/CSV...CLOUDS DECK IS GOING TO BE SLOW TO
ERODE, WITH VFR CIGS LASTING INTO THE EVENING AT BNA AND CSV. CIGS
WILL ALTERNATE BETWEEN IFR & MVFR AT CSV AS BANDS OF LIGHT SNOW
MOVE ACROSS EASTERN MIDDLE TENNESSEE DURING THE MORNING. CLOUDS
WILL IMPROVE TO VFR LATER IN THE DAY AS THE DEEPEST MOISTURE PULLS
OUT.
&&
.PREV DISCUSSION... /ISSUED 315 AM CST TUE JAN 27 2015/
DISCUSSION...
CURRENTLY...SOME LIGHT SNOW INDICATED OVER CENTRAL AREAS OF KY.
LATEST MODEL RUNS SUPPORT THE SOUTHWARD MOVING IMPULSE.
HOWEVER...BEST REGION OF PVA THROUGH THE MORNING HOURS WILL BE
MAINLY EAST OF THE MID STATE...NORTHERN AREAS OF THE PLATEAU MAY
BE ON THE WESTERN FRINGE. THUS...WITH HRRR IN AGREEMENT WITH
TRENDING TOWARD LESS IN THE WAY OF SNOWFALL...WILL OPT TO TREND
DOWNWARD THE SNOW THREAT. HALF INCH ACCUMULATIONS WILL BE POSSIBLE
FOR THE NORTHERN PLATEAU ONLY FOR THIS MORNING...GENERALLY A TRACE TO A
QUARTER INCH ELSEWHERE ACROSS THE PLAT. AREAS JUST WEST OF THE
PLATEAU COULD SEE A FEW FLURRIES. OTHERWISE...CLOUDS WILL HANG ON
THROUGH TODAY...BUT CLEARING LINE NOT TOO FAR OFF TO THE
SOUTHWEST.
PARTIAL CLEARING WILL BEGIN TONIGHT AS HIGH PRESSURE SETTLES IN JUST
TO OUR NORTH. COLD TEMPS FOR TONIGHT WITH LOWS RANGING FROM NEAR 20
PLATEAU...AND MOSTLY LOWER TO MID 20S ELSEWHERE.
SUNSHINE WILL BE THE RULE FOR WEDNESDAY. A WEAK RIDGE AXIS WILL
STRETCH ACROSS THE MID STATE SO WE SHOULD SEE TEMPS WARM UP CLOSE TO
50 DEGREES FOR MOST AREAS.
A CLIPPER SYSTEM WILL THEN BE ON APPROACH AND THE ASSOCIATED
FRONTAL BOUNDARY WILL MOVE THROUGH ON THURSDAY. THIS WILL
TRANSLATE TO A CHANCE OF SHOWERS LATE WED NT INTO THURSDAY. THE
SFC LOW WILL PASS A GOOD DISTANCE TO THE NORTH OF TN. TEMPS WILL
THEREFORE REACH INTO THE LOWER TO MID 50S DURING THE DAY.
IN THE EXT FCST...COLDER AND MORE SEASONAL AIR WILL WORK IN BEHIND
THE CLIPPER SYSTEM. THEN...THE GULF STORM...THAT WE HAVE BEEN
LOOKING AT FOR SEVERAL DAYS NOW...WILL BEGIN TO GET ITS ACT
TOGETHER. FOR SEVERAL RUNS NOW...THE EURO MODEL WAS COLDER AND WAS
SUPPORTING A POTENTIAL SNOW EVENT WHILE THE GFS WAS A WARMER RAIN
SCENARIO. WELL...THE EURO HAS BACKED OFF AND IS NOW SHOWING MORE OF
A N-S TROUGH INVERSION AS OPPOSED TO THE COLDER W-E AXIS. THIS NOW
MATCHES UP WITH THE WARMER GFS SOLUTION. THUS...WILL TREND TOWARD
MORE OF A RAIN EVENT FOR SAT NT INTO SUNDAY. AT ANY RATE...LOOKS
LIKE ABOUT 1/2 TO PERHAPS 3/4 INCH RAINFALL AMOUNTS.
COLD AIR TO WORK INTO THE AREA BY SUNDAY AS THE MOISTURE IS PULLING
OUT. WILL INCLUDE A SLIGHT CHANCE OF SNOW.
MON AND TUES OF NEXT WEEK LOOK COLD...BUT NOTHING TOO BAD AS UPPER
FLOW IS MORE WESTERLY. SPLIT FLOW IS INDICATED BUT THE SOUTHERN JET
WILL BE WELL SOUTH OF THE AREA. JUST DRY WITH TEMPS 5 DEGREES OR SO
BELOW NORMAL.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
ROSE
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
411 PM CST TUE JAN 27 2015
.SHORT TERM...
304 PM CST
THROUGH THURSDAY...
PRIMARY CONCERN IN THE NEAR TERM REVOLVES AROUND THE STRATUS DECK
CURRENTLY OVER THE SOUTHWESTERN 2/3RDS OF THE CWA. WOULD ANTICIPATE
A CONTINUED VERY SLOW CLEARING FROM THE EAST FOR A COUPLE MORE HOURS
BEFORE LOW LEVEL FLOW DIMINISHES THIS EVENING BEFORE BACKING TO
SOUTHERLY OVERNIGHT...WHICH MAY WELL SEND STRATUS SLOSHING BACK
NORTH INTO AREAS THAT HAD PREVIOUSLY CLEARED OUT. TRIED TO REFLECT A
TREND LIKE THIS IN THE HOURLY SKY GRIDS AND RESULTANT TEMPERATURE
GRIDS...BUT GIVEN THE POOR MODEL HANDLING OF THIS CLOUDINESS IT
PRETTY MUCH GUARANTEED THAT OUR CURRENT SKY GRIDS WILL BE WRONG
SOMEWHERE AND NEED UPDATING WITH ACCOMPANYING CHANGES NEEDED IN
TEMPS TONIGHT. WHERE SKIES BECOME/STAY CLEAR TONIGHT COULD SEE
FREEZING GROUND FOG DEVELOP GIVEN THE LIGHT WINDS...BUT WILL LET
EVENING SHIFT WATCH TRENDS AND ADD FREEZING FOG AS NEEDED.
FOR WEDNESDAY HAVE OPTED TO BE OPTIMISTIC IN PUSHING STRATUS NORTH
AND BREAKING IT UP IN THE MORNING BUT THIS VERY WELL MAY END UP
BEING TOO OPTIMISTIC. ASSUMING THERE IS SOME SUNSHINE TOMORROW PRIOR
TO THE ARRIVAL OF EXTENSIVE MID AND HIGH LEVEL CLOUDINESS THEN HIGHS
COULD PUSH WELL INTO THE 30S...PARTICULARLY IN THE LESS SNOW COVERED
AND MORE URBANIZED AREAS. DEVELOPING LOW PRESSURE TO OUR WEST
SHOULD RESULT IN TIGHTENING PRESSURE GRADIENT AND STRENGTHENING
SOUTHERLY WINDS WEDNESDAY.
IZZI
&&
.LONG TERM...
304 PM CST
THURSDAY NIGHT THROUGH TUESDAY...
BRISK SOUTH WINDS...WARM AIR ADVECTION...AND CLOUD COVER IN ADVANCE
OF THE SYSTEM WEDNESDAY NIGHT SHOULD RESULT IN NEARLY STEADY TEMPS
IN THE EVENING AND PROBABLY RISING A BIT OVERNIGHT. COULD SEE A BIT
OF LIGHT RAIN OR DRIZZLE IN THE WARM SECTOR WEDNESDAY NIGHT FOLLOWED
BY SOME POTENTIAL FOR A BIT OF WRAP AROUND RAIN OR SNOW SHOWERS
THURSDAY ON THE BACK SIDE OF THE SYSTEM. STILL LOOKS LIKE PRETTY
LIMITED MOISTURE WITH THE SYSTEM AND HIGHEST QPF FOCUSED TO OUR
NORTH WITH LIGHT AMOUNTS IN OUR CWA AND ONLY MINIMAL THREAT OF ANY
ACCUMULATED FROZEN/FREEZING PRECIP GIVEN THE FORECAST TRACK AND
TEMPS.
SHOT OF SEASONABLY COLD AIR WILL KNOCK TEMPS TO JUST A HAIR BELOW
AVERAGE FRIDAY. VIGOROUS ALBERTA CLIPPER IS FORECAST TO RESULT IN
AN AMPLIFYING LONG WAVE TROUGH OVER THE CENTRAL CONUS THIS WEEKEND.
STILL SOME LARGE SPREAD BETWEEN MODELS WITH RESPECT TO THE DETAILS
THIS WEEKEND...BUT THERE HAS BEEN SOME AGREEMENT THE PAST COUPLE
DAYS ON THE GENERAL IDEA OF A LARGE SWATH OF ACCUMULATING SNOW
POTENTIALLY AFFECTING THE REGION SAT NIGHT INTO SUNDAY. ARCTIC AIR
IS FORECAST TO SURGE SOUTH INTO THE AREA IN THE WAKE OF THIS SYSTEM
EARLY NEXT WEEK...BUT THE DURATION AND MAGNITUDE OF THIS ARCTIC
INTRUSION ARE DEPENDENT ON WHICH MODEL YOU LOOK AT MEANING FAIRLY
LOW FORECAST CONFIDENCE AT THIS POINT.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* GUSTY SSELY WINDS TOMORROW.
* CHANCE FOR MVFR CIGS OR VIS LATE TONIGHT.
KREIN
//DISCUSSION...UPDATED 18Z...
BROAD MVFR STRATUS DECK BLANKETS THE REGION TODAY BUT HAS BEEN
STEADILY ERODING FROM THE NORTHEAST...WITH CLEARING SKIES MAKING
PROGRESS DOWN LAKE MICHIGAN THIS MORNING AND INTO THE CHICAGO AREA
EARLY THIS AFTERNOON. CLOUD BEARING FLOW OUT OF THE NORTHEAST THIS
MORNING WILL BACK TO THE NORTH THIS AFTERNOON AND EVENING SO EXPECT
THE PROGRESS OF THE CLEARING TO SLOW SOME...AND MAY EVEN REVERSE
TONIGHT AS A SURFACE RIDGE BUILDS ACROSS INDIANA WITH FLOW BECOMING
MORE SOUTHERLY. SURFACE WINDS WILL GENERALLY DECREASE FROM MID
AFTERNOON ON AS THE SURFACE HIGH NEARS...AND GO LIGHT AND
VARIABLE FOR A PERIOD THIS EVENING AND OVERNIGHT...BEFORE TURNING
SOUTH/SOUTH-SOUTHEAST TOMORROW. GUSTY WINDS PUSHING 20 KT ARE
EXPECTED TOMORROW AFTERNOON.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* LOW-MEDIUM CONFIDENCE IN CIG/VIS TRENDS OVERNIGHT.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...CHANCE OF RAIN/DRIZZLE. MVFR/IFR POSSIBLE.
THURSDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY/IFR POSSIBLE.
FRIDAY AND SATURDAY...PRIMARILY VFR. CHANCE OF SNOW SATURDAY
NIGHT.
SUNDAY...CHANCE OF LIGHT SNOW. IFR POSSIBLE.
MONDAY...MVFR CIGS POSSIBLE.
RATZER
&&
.MARINE...
318 PM CST
LIGHTER NORTHERLY WINDS IN PLACE THIS AFTERNOON AS HIGH PRESSURE
SPANS THE REGION...WILL FURTHER DIMINISH THIS EVENING AS THIS HIGH
MOVES OVERHEAD. THIS HIGH WILL THEN CONTINUE SOUTHEAST TOWARDS THE
OHIO VALLEY TONIGHT AS A TROUGH OF LOW PRESSURE MOVES EAST ACROSS
THE CENTRAL PLAINS. THIS WILL HELP THE WINDS TO TURN BACK MORE
SOUTHERLY AND THEN BEGIN TO SLOWLY INCREASE LATER TONIGHT INTO
WEDNESDAY. THIS INCREASING TREND WILL CONTINUE THROUGHOUT THE DAY
WEDNESDAY...WITH SOUTHERLY WINDS REALLY INCREASING DURING THE
AFTERNOON TIME FRAME. THIS WILL LIKELY CREATE WINDS HAZARDOUS FOR
SMALL CRAFT...AND SO HAVE ISSUED A SMALL CRAFT ADVISORY FOR
WEDNESDAY AFTERNOON THROUGH LATE WEDNESDAY NIGHT WHEN WINDS WILL
DIMINISH WITH THE APPROACHING LOW PRESSURE. THIS WILL LIKELY BE
BRIEF AS WINDS WILL QUICKLY INCREASE ONCE AGAIN ON THE BACKSIDE OF
THIS SYSTEM THURSDAY. ALSO...SOUTHERLY WINDS ACROSS THE SOUTHERN
HALF OF THE LAKE COULD HOVER AROUND 30 KT A FOR A BRIEF WINDOW
WEDNESDAY NIGHT. WILL NEED TO MONITOR TRENDS DURING THIS
PERIOD...BUT WILL MAKE MENTION OF OCCASIONAL GALE FORCE GUSTS
DURING THIS TIME. EXPECT STRONG WINDS TO BE IN PLACE ON
THURSDAY...REALLY INCREASING INTO THE AFTERNOON AND EVENING HOURS.
GALES ARE APPEARING LIKELY FOR THE ENTIRE LAKE DURING THIS
TIME...EVEN FOR THE NEARSHORE WATERS...BUT WITH SPEEDS DIMINISHING
ONCE AGAIN LATE THURSDAY NIGHT INTO FRIDAY.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...NOON WEDNESDAY TO 4 AM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
ISSUED BY NATIONAL WEATHER SERVICE CHICAGO IL
341 PM CST Tue Jan 27 2015
.SHORT TERM...(Through Wednesday afternoon)
ISSUED AT 255 PM CST TUE JAN 27 2015
MAIN CHALLENGE IN THE SHORT/NEAR TERM REVOLVES AROUND CLOUD COVER
TONIGHT...WINDS AND TEMPS ON WEDNESDAY. A SURFACE RIDGE IS IN PLACE
OVERHEAD...AND SATELLITE PICTURES SHOW LOWER CLOUDS ERODING FROM THE
NORTHEAST THIS AFTERNOON AS DRIER AIR FILTERS IN. BEST CHANCES FOR
EROSION WILL BE FOR EASTERN AREAS WHERE THIS DRIER AIR IS MAKING
BETTER HEADWAY. RAW MODEL GUIDANCE CONTINUES TO ADVERTISE CLEARING
MUCH SOONER THIS EVENING AREA-WIDE...WHILE RAP TIME HEIGHTS SUGGEST
IT WILL TAKE UNTIL LATER TONIGHT FOR THIS TO OCCUR...ESPECIALLY
NORTH OF I-72. MODEL SOUNDINGS SUGGEST THAT THIS LOWER LEVEL
MOISTURE WILL REMAIN TRAPPED BELOW A SUBSIDENCE INVERSION...AND THAT
IT WILL AT LEAST HOLD FIRM THROUGH THE EVENING HOURS. CLOUD BEARING
WINDS WILL BE TURNING MORE NORTHERLY AS WELL...WHICH WOULD SUPPORT
CLOUDS HANGING ON ALONG AND WEST OF HIGHWAY 51. SURFACE HIGH
PRESSURE TONIGHT WILL SHIFT OFF THE EAST TONIGHT AS THE UPPER RIDGE
IN THE PLAINS MOVE EAST AND CONTINUES TO DEAMPLIFY. EXPECT WINDS TO
SHIFT TO THE SE OVERNIGHT...WITH LOWS IN THE EAST IN THE UPPER TEENS
TO NEAR 20...WITH 20S HOLDING WEST WHERE CLOUD COVER IS EXPECTED TO
BE MORE PREVALENT.
THURSDAY...ATTENTION SHIFTS TO UPPER LEVEL LOW PRESSURE MOVING
THROUGH THE GREAT BASIN THIS AFTERNOON. THE UPPER TROUGH MOVES INTO
THE PLAINS RIDGE WHILE ADDITIONAL PACIFIC ENERGY MOVES INTO THE
NORTHERN PLAINS. LOW LEVEL WARM ADVECTION ENSUES IN THE
SOUTHWESTERLY FLOW AHEAD OF THESE SYSTEM .IT APPEARS THAT NOT ALL OF
OF THIS LOW LEVEL WARMING WILL NOT TRANSLATE TO THE SURFACE WITH A
FAIRLY STRONG INVERSION HOLDING...BUT DO EXPECT SOME WARMING FROM
TODAY`S READINGS...ESPECIALLY FOR SOUTHERN AND WESTERN AREAS WHERE
MID 40S LOOK LIKE A DECENT BET. AREAS NORTH AND EAST WILL REMAIN ON
THE COOLER SIDE STRUGGLING TO REACH 40. AHEAD OF THESE TWO
DISTURBANCES SURFACE LOW PRESSURE OF 1005 MB COMBINES WITH THE
DEPARTING HIGH TO CREATE A MODEST PRESSURE GRADIENT ACROSS THE AREA.
A VERY STRONG LOW LEVEL JET SETS UP LATE IN THE AFTERNOON...BUT
GIVEN THE LOW LEVEL INVERSION...EXPECT A BREEZY DAY WITH GUSTS IN
THE 25 KT RANGE.
KMD
&&
.LONG TERM...(Wednesday Night through Tuesday)
ISSUED AT 340 PM CST TUE JAN 27 2015
WEDNESDAY NIGHT THROUGH SATURDAY...
A WINDY AND MILD NIGHT IS IN STORE ON WEDNESDAY NIGHT AS LOW
PRESSURE QUICKLY MOVES JUST NORTH OF THE CWA. STRONG PRESSURE
FALLS DUE TO TIGHTENING GRADIENT BETWEEN ADVANCING LOW AND
DEPARTING HIGH PRESSURE TO THE EAST WILL RESULT IN SUSTAINED
SOUTHERLY WINDS IN THE MID TO HIGH TEENS WITH GUSTS OF 20-25 KT.
TEMPERATURES SHOULD DROP SOME IN THE EVENING BUT THEN ARE LIKELY
TO SLOWLY RISE TOWARD DAYBREAK. THERE IS A DECENT VORT MAX
ASSOCIATED WITH APPROACHING SHORT WAVE TROUGH...BUT GUIDANCE IS
FAIRLY DRY WITH EXCEPTION OF ECMWF AND NAM. MAINTAINED SLIGHT TO
LOW END CHANCE POPS FOR LIGHT RAIN MAINLY AFTER MIDNIGHT. MAY NEED
TO ADD DRIZZLE TO GRIDS.
COLD FRONT TRAILING FROM THE LOW PRESSURE WILL SWEEP ACROSS THE
AREA FROM NW TO SE OVERNIGHT INTO THURSDAY MORNING...SHIFTING
WINDS FROM SOUTHWEST TO NORTHWEST...AND COLD ADVECTION RAMPING UP
BEHIND IT. HAVE LOW POPS FOR MOST OF THE CWA IN THE MORNING...BUT
ANY PRECIP WOULD LIKELY BE LIGHT RAIN DESPITE COLD ADVECTION AS
SURFACE TEMPERATURES WOULDNT COOL QUICK ENOUGH FROM EARLY HIGHS IN
THE UPPER 30S TO MID 40S...WARMEST FAR SOUTHEAST. BIGGER STORY
WILL BE STRONG ISALLOBARIC PRESSURE RISES BEHIND FRONT RESULTING
IN NORTHWEST WINDS GUSTING TO 30-35 MPH MUCH OF THE MORNING AND
AFTERNOON. WINDS WILL GRADUALLY DIMINISH THURSDAY NIGHT AS
EXPANSIVE HIGH PRESSURE SPREADS SOUTHEAST. EXPECT LOWS IN THE
UPPER TEENS TO MID 20S BY EARLY FRIDAY...RECOVERING TO SLIGHTLY
BELOW CLIMO LOW-MID 30S UNDER LARGE CANADIAN HIGH. THE HIGH WILL
SLIDE SOUTHEAST ON SATURDAY...ALLOWING TEMPS TO WARM SLIGHTLY TO
THE MID TO UPPER 30S.
SATURDAY NIGHT THROUGH TUESDAY...
ATTENTION TURNS TO EJECTION OF CLOSED UPPER LOW OVER THE DESERT
SOUTHWEST AS MORE OF AN OPEN WAVE SATURDAY NIGHT INTO
SUNDAY...WITH ASSOCIATED WEAK SURFACE LOW POSSIBLY MOVING TOWARD
THE LOWER OR MID MS VALLEY THEN OH VALLEY BY SUNDAY EVENING. WITH
IT BEING STILL OVER 100 HRS OUT...GUIDANCE VARIES ON PLACEMENT OF
SURFACE LOW...BUT DECENT AGREEMENT IN OPERATIONAL MODELS AND
ENSEMBLES OF BROAD WARM ADVECTION/ISENTROPIC ASCENT WITH THIS
SYSTEM. THIS YIELDS THE POTENTIAL FOR FAIRLY LONG DURATION
PRECIPITATION. AT THIS POINT...THERMAL PROFILES APPEAR COLD ENOUGH
FOR SNOW ACROSS THE CWA...BUT FARTHER NORTHWEST/STRONGER LOW COULD
INTRODUCE P-TYPE CONCERNS...ESPECIALLY IN THE FAR SOUTHEAST. WAY
TOO EARLY TO DISCUSS POTENTIAL SNOW ACCUMULATIONS...BUT THIS
PERIOD BEARS WATCHING. BEHIND THIS SYSTEM...MODELS HAVE BEEN
WAFFLING ON INTENSITY OF A POTENTIAL SHOT OF ARCTIC AIR EARLY NEXT
WEEK AS PIECE OF POLAR VORTEX ROTATES SOUTH OF HUDSON BAY. BRUNT
OF THE ARCTIC BLAST MAY BE DIRECTED FARTHER EAST...BUT STILL LOOKS
LIKE THERE COULD BE A PERIOD OF WELL BELOW NORMAL TEMPERATURES
EARLY NEXT WEEK.
RC
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1141 AM CST TUE JAN 27 2015
MAIN AVIATION CONCERN REVOLVES AROUND EXISTING MVFR AND IFR CIGS.
IFR CIGS ARE BECOMING LESS COMMON ACROSS THE TERMINALS AS DRIER
AIR SLOWLY FILTERS IN FROM THE NORTHEAST. EXPECT KBMI WILL HANG
ONTO IFR A BIT LONGER BEFORE TRANSITION MVFR CIGS IN THE 1000-1500
FT RANGE. CHALLENGE THEN TURNS TO HOW QUICKLY THE LOWER CLOUD BASE
ERODES. HRRR AND RAP GUIDANCE ARE A BIT MIXED TO HOW QUICKLY THIS
OCCURS. THE GENERAL FEELING IS THAT SOMETIME THIS EVENING THE MVFR
DECK WILL LIFT ABOVE 2000 FT AND SCATTER OUT AS THE HRRR
SUGGESTS...BUT CONFIDENCE ON THIS TIMING IS MEDIUM. HIGHEST CONFIDENCE
ON TIMING THIS OCCURRENCE IS AT KCMI AND EASTERN LOCATIONS WHERE
DRIER AIR WILL MORE READILY ADVECT IN. MEANWHILE THE RAP AND NAM
HOLD ONTO THE CLOUDS THROUGH 6Z OR SLIGHTLY LATER AS A LOW LEVEL
INVERSION REMAINS IN PLACE. WINDS OVERNIGHT WILL VEER TO THE
SOUTHEAST AND WEAKEN BEFORE STRENGTHENING TOMORROW MORNING. SOME
PATCHY FOG MAY DEVELOP AFTER CLOUDS CLEAR BUT HELD OFF ANY MENTION
AT THIS POINT.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...kmd
LONG TERM...RC
AVIATION...KMD
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
304 PM CST TUE JAN 27 2015
.SHORT TERM...
304 PM CST
THROUGH THURSDAY...
PRIMARY CONCERN IN THE NEAR TERM REVOLVES AROUND THE STRATUS DECK
CURRENTLY OVER THE SOUTHWESTERN 2/3RDS OF THE CWA. WOULD ANTICIPATE
A CONTINUED VERY SLOW CLEARING FROM THE EAST FOR A COUPLE MORE HOURS
BEFORE LOW LEVEL FLOW DIMINISHES THIS EVENING BEFORE BACKING TO
SOUTHERLY OVERNIGHT...WHICH MAY WELL SEND STRATUS SLOSHING BACK
NORTH INTO AREAS THAT HAD PREVIOUSLY CLEARED OUT. TRIED TO REFLECT A
TREND LIKE THIS IN THE HOURLY SKY GRIDS AND RESULTANT TEMPERATURE
GRIDS...BUT GIVEN THE POOR MODEL HANDLING OF THIS CLOUDINESS IT
PRETTY MUCH GUARANTEED THAT OUR CURRENT SKY GRIDS WILL BE WRONG
SOMEWHERE AND NEED UPDATING WITH ACCOMPANYING CHANGES NEEDED IN
TEMPS TONIGHT. WHERE SKIES BECOME/STAY CLEAR TONIGHT COULD SEE
FREEZING GROUND FOG DEVELOP GIVEN THE LIGHT WINDS...BUT WILL LET
EVENING SHIFT WATCH TRENDS AND ADD FREEZING FOG AS NEEDED.
FOR WEDNESDAY HAVE OPTED TO BE OPTIMISTIC IN PUSHING STRATUS NORTH
AND BREAKING IT UP IN THE MORNING BUT THIS VERY WELL MAY END UP
BEING TOO OPTIMISTIC. ASSUMING THERE IS SOME SUNSHINE TOMORROW PRIOR
TO THE ARRIVAL OF EXTENSIVE MID AND HIGH LEVEL CLOUDINESS THEN HIGHS
COULD PUSH WELL INTO THE 30S...PARTICULARLY IN THE LESS SNOW COVERED
AND MORE URBANIZED AREAS. DEVELOPING LOW PRESSURE TO OUR WEST
SHOULD RESULT IN TIGHTENING PRESSURE GRADIENT AND STRENGTHENING
SOUTHERLY WINDS WEDNESDAY.
IZZI
&&
.LONG TERM...
304 PM CST
THURSDAY NIGHT THROUGH TUESDAY...
BRISK SOUTH WINDS...WARM AIR ADVECTION...AND CLOUD COVER IN ADVANCE
OF THE SYSTEM WEDNESDAY NIGHT SHOULD RESULT IN NEARLY STEADY TEMPS
IN THE EVENING AND PROBABLY RISING A BIT OVERNIGHT. COULD SEE A BIT
OF LIGHT RAIN OR DRIZZLE IN THE WARM SECTOR WEDNESDAY NIGHT FOLLOWED
BY SOME POTENTIAL FOR A BIT OF WRAP AROUND RAIN OR SNOW SHOWERS
THURSDAY ON THE BACK SIDE OF THE SYSTEM. STILL LOOKS LIKE PRETTY
LIMITED MOISTURE WITH THE SYSTEM AND HIGHEST QPF FOCUSED TO OUR
NORTH WITH LIGHT AMOUNTS IN OUR CWA AND ONLY MINIMAL THREAT OF ANY
ACCUMULATED FROZEN/FREEZING PRECIP GIVEN THE FORECAST TRACK AND
TEMPS.
SHOT OF SEASONABLY COLD AIR WILL KNOCK TEMPS TO JUST A HAIR BELOW
AVERAGE FRIDAY. VIGOROUS ALBERTA CLIPPER IS FORECAST TO RESULT IN
AN AMPLIFYING LONG WAVE TROUGH OVER THE CENTRAL CONUS THIS WEEKEND.
STILL SOME LARGE SPREAD BETWEEN MODELS WITH RESPECT TO THE DETAILS
THIS WEEKEND...BUT THERE HAS BEEN SOME AGREEMENT THE PAST COUPLE
DAYS ON THE GENERAL IDEA OF A LARGE SWATH OF ACCUMULATING SNOW
POTENTIALLY AFFECTING THE REGION SAT NIGHT INTO SUNDAY. ARCTIC AIR
IS FORECAST TO SURGE SOUTH INTO THE AREA IN THE WAKE OF THIS SYSTEM
EARLY NEXT WEEK...BUT THE DURATION AND MAGNITUDE OF THIS ARCTIC
INTRUSION ARE DEPENDENT ON WHICH MODEL YOU LOOK AT MEANING FAIRLY
LOW FORECAST CONFIDENCE AT THIS POINT.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS CLEARING THE TERMINALS EARLY THIS AFTERNOON...BUT
LIKELY REMAIN NEARBY THIS EVENING AND TONIGHT.
BMD
//DISCUSSION...UPDATED 18Z...
BROAD MVFR STRATUS DECK BLANKETS THE REGION TODAY BUT HAS BEEN
STEADILY ERODING FROM THE NORTHEAST...WITH CLEARING SKIES MAKING
PROGRESS DOWN LAKE MICHIGAN THIS MORNING AND INTO THE CHICAGO AREA
EARLY THIS AFTERNOON. CLOUD BEARING FLOW OUT OF THE NORTHEAST THIS
MORNING WILL BACK TO THE NORTH THIS AFTERNOON AND EVENING SO EXPECT
THE PROGRESS OF THE CLEARING TO SLOW SOME...AND MAY EVEN REVERSE
TONIGHT AS A SURFACE RIDGE BUILDS ACROSS INDIANA WITH FLOW BECOMING
MORE SOUTHERLY. SURFACE WINDS WILL GENERALLY DECREASE FROM MID
AFTERNOON ON AS THE SURFACE HIGH NEARS...AND GO LIGHT AND
VARIABLE FOR A PERIOD THIS EVENING AND OVERNIGHT...BEFORE TURNING
SOUTH/SOUTH-SOUTHEAST TOMORROW. GUSTY WINDS PUSHING 20 KT ARE
EXPECTED TOMORROW AFTERNOON.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN PERIODS OF VFR THIS AFTERNOON...LOW-MEDIUM
CONFIDENCE IN CIG TRENDS OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...CHANCE OF RAIN/DRIZZLE. MVFR/IFR POSSIBLE.
THURSDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY/IFR POSSIBLE.
FRIDAY AND SATURDAY...PRIMARILY VFR. CHANCE OF SNOW SATURDAY
NIGHT.
SUNDAY...CHANCE OF LIGHT SNOW. IFR POSSIBLE.
MONDAY...MVFR CIGS POSSIBLE.
RATZER
&&
.MARINE...
213 AM CST
MARINE CONCERNS ON LAKE MICHIGAN ARE A PERIOD OF STRONG SOUTH WINDS
WEDNESDAY AFTERNOON AND NIGHT...THEN A SHIFT TO STRONG NORTH TO
NORTHWEST WINDS THURSDAY AFTERNOON INTO EARLY FRIDAY...WITH THE
POTENTIAL FOR A PERIOD OF NORTHWEST GALES ESPECIALLY THURSDAY
AFTERNOON AND THURSDAY EVENING.
IN THE NEAR TERM...RELATIVELY QUIET WEATHER ACROSS THE LAKE EARLY
THIS MORNING AS A WEAKENING SURFACE TROUGH OVER ILLINOIS AND THE
LOWER OHIO VALLEY CONTINUES TO MOVE OFF TO THE SOUTHEAST...ALLOWING
WEAK HIGH PRESSURE TO SETTLE ACROSS THE AREA FROM THE NORTH TODAY.
LOOKING TO THE WEST...AN AREA OF LOW PRESSURE DEVELOPING IN THE LEE
OF THE CANADIAN ROCKIES WILL SLIDE SOUTHEAST INTO THE PLAINS
THROUGH TONIGHT...THEN WILL MOVE SLOWLY EAST TOWARD LAKE MICHIGAN
WEDNESDAY AND WEDNESDAY NIGHT. IN RESPONSE TO PRESSURE FALLS AHEAD
OF THE LOW...THE GRADIENT WILL TIGHTEN ACROSS LAKE MICHIGAN
WEDNESDAY WITH SOUTH WINDS RAMPING UP INTO THE 30 KT RANGE BY LATE
AFTERNOON AND EVENING. WINDS WILL DIMINISH BRIEFLY EARLY THURSDAY
MORNING AS THE LOW PRESSURE CENTER AND COLD FRONTAL TROUGH CROSS THE
LAKE...BEFORE WINDS SHIFT TO THE NORTH-NORTHWEST AND INCREASE
QUICKLY BACK INTO THE 30-35 KT RANGE THURSDAY AFTERNOON. FORECAST
SOUNDINGS INDICATE THE POTENTIAL FOR GALES THURSDAY AFTERNOON AND
EVENING IN THE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND THE
DEPARTING LOW AND COLD FRONT. THESE STRONG WINDS WILL CONTINUE INTO
EARLY FRIDAY...BEFORE DIMINISHING AS A BROAD AREA OF HIGH PRESSURE
SPREADS INTO THE AREA BY FRIDAY EVENING. THE HIGH WILL SLOWLY MOVE
OFF TO THE EAST ON SATURDAY...WITH A WEAK LOW EXPECTED TO PASS
ACROSS THE NORTHERN LAKES SATURDAY NIGHT AND TRAIL A COLD FRONT
ACROSS LAKE MICHIGAN THROUGH SUNDAY.
FOR THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE WATERS SMALL CRAFT
ADVISORY CONDITIONS LOOK TO DEVELOP WEDNESDAY AFTERNOON AND CONTINUE
THROUGH THURSDAY MORNING...WITH A BRIEF BREAK BEFORE HIGH WIND/WAVE
CONDITIONS DEVELOP AGAIN BY EARLY THURSDAY AFTERNOON. HIGH WAVES
WOULD LIKELY LINGER THROUGH MUCH OF FRIDAY...ESPECIALLY ALONG THE
INDIANA SHORE EAST OF GARY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...NOON WEDNESDAY TO 4 AM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
ISSUED BY NATIONAL WEATHER SERVICE CHICAGO IL
259 PM CST Tue Jan 27 2015
.SHORT TERM...(Through wednesday afternoon)
ISSUED AT 255 PM CST TUE JAN 27 2015
MAIN CHALLENGE IN THE SHORT/NEAR TERM REVOLVES AROUND CLOUD COVER
TONIGHT...WINDS AND TEMPS ON WEDNESDAY. A SURFACE RIDGE IS IN PLACE
OVERHEAD...AND SATELLITE PICTURES SHOW LOWER CLOUDS ERODING FROM THE
NORTHEAST THIS AFTERNOON AS DRIER AIR FILTERS IN. BEST CHANCES FOR
EROSION WILL BE FOR EASTERN AREAS WHERE THIS DRIER AIR IS MAKING
BETTER HEADWAY. RAW MODEL GUIDANCE CONTINUES TO ADVERTISE CLEARING
MUCH SOONER THIS EVENING AREA-WIDE...WHILE RAP TIME HEIGHTS SUGGEST
IT WILL TAKE UNTIL LATER TONIGHT FOR THIS TO OCCUR...ESPECIALLY
NORTH OF I-72. MODEL SOUNDINGS SUGGEST THAT THIS LOWER LEVEL
MOISTURE WILL REMAIN TRAPPED BELOW A SUBSIDENCE INVERSION...AND THAT
IT WILL AT LEAST HOLD FIRM THROUGH THE EVENING HOURS. CLOUD BEARING
WINDS WILL BE TURNING MORE NORTHERLY AS WELL...WHICH WOULD SUPPORT
CLOUDS HANGING ON ALONG AND WEST OF HIGHWAY 51. SURFACE HIGH
PRESSURE TONIGHT WILL SHIFT OFF THE EAST TONIGHT AS THE UPPER RIDGE
IN THE PLAINS MOVE EAST AND CONTINUES TO DEAMPLIFY. EXPECT WINDS TO
SHIFT TO THE SE OVERNIGHT...WITH LOWS IN THE EAST IN THE UPPER TEENS
TO NEAR 20...WITH 20S HOLDING WEST WHERE CLOUD COVER IS EXPECTED TO
BE MORE PREVALENT.
THURSDAY...ATTENTION SHIFTS TO UPPER LEVEL LOW PRESSURE MOVING
THROUGH THE GREAT BASIN THIS AFTERNOON. THE UPPER TROUGH MOVES INTO
THE PLAINS RIDGE WHILE ADDITIONAL PACIFIC ENERGY MOVES INTO THE
NORTHERN PLAINS. LOW LEVEL WARM ADVECTION ENSUES IN THE
SOUTHWESTERLY FLOW AHEAD OF THESE SYSTEM .IT APPEARS THAT NOT ALL OF
OF THIS LOW LEVEL WARMING WILL NOT TRANSLATE TO THE SURFACE WITH A
FAIRLY STRONG INVERSION HOLDING...BUT DO EXPECT SOME WARMING FROM
TODAY`S READINGS...ESPECIALLY FOR SOUTHERN AND WESTERN AREAS WHERE
MID 40S LOOK LIKE A DECENT BET. AREAS NORTH AND EAST WILL REMAIN ON
THE COOLER SIDE STRUGGLING TO REACH 40. AHEAD OF THESE TWO
DISTURBANCES SURFACE LOW PRESSURE OF 1005 MB COMBINES WITH THE
DEPARTING HIGH TO CREATE A MODEST PRESSURE GRADIENT ACROSS THE AREA.
A VERY STRONG LOW LEVEL JET SETS UP LATE IN THE AFTERNOON...BUT
GIVEN THE LOW LEVEL INVERSION...EXPECT A BREEZY DAY WITH GUSTS IN
THE 25 KT RANGE.
KMD
&&
.LONG TERM...(Tonight through Tuesday)
ISSUED AT 326 AM CST TUE JAN 27 2015
Low clouds to decrease during the evening as 1027 mb high pressure
drifts over IL/IN by overnight. Lows tonight range from upper teens
to near 20F ne counties (where clearing may occur soonest) to mid
20s sw counties. High pressure drifts east into eastern Ohio river
valley by 18Z/noon Wed and get a breezy SSE flow developing over IL
and bringing in milder air with partly to mostly sunny skies. Highs
Wed range from lower 40s eastern IL to the upper 40s to around 50F
from Jacksonville west to the MS river.
Low pressure ejects east from northern Rockies into western Great
Lakes by dawn Thu and pulls cold front east across IL late Wed night
into Thu morning. This to bring chances of light rain overnight Wed
night into Thu morning and possibly lingering over eastern IL Thu
afternoon where light snow could mix in over northern counties
before ending. Lows Wed night of 33-38F with coolest readings in
east central IL. Highs Thu in upper 30s and lower 40s central IL and
mid 40s in southeast IL southeast of I-70.
1040 mb Canadian high pressure moves down into the Midwest Friday
and returns mostly clear to partly cloudy skies and cooler
temperatures Thu night through Fri night. Cooler highs Friday of
30-35F. Most of Saturday now appears dry over central and eastern IL
with chance of light snow/rain moving into west central IL later
Saturday ahead of next storm system. Seasonable highs Saturday in mid
to upper 30s.
00Z extended models show more phasing of southern and northern
stream system this weekend and bring better chances of light snow to
central and southeast IL Sat night into Sunday evening as surface
low deepens ne from southeast Texas into the eastern OH/TN river
valleys. This could bring a few inches of snow accumulations
especially in southeast IL where even a mix of precipitation appears
possible south of Highway 50. Another Canadian high to drift
southeast into IL early next work week bringing colder/below normal
temperatures.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1141 AM CST TUE JAN 27 2015
MAIN AVIATION CONCERN REVOLVES AROUND EXISTING MVFR AND IFR CIGS.
IFR CIGS ARE BECOMING LESS COMMON ACROSS THE TERMINALS AS DRIER
AIR SLOWLY FILTERS IN FROM THE NORTHEAST. EXPECT KBMI WILL HANG
ONTO IFR A BIT LONGER BEFORE TRANSITION MVFR CIGS IN THE 1000-1500
FT RANGE. CHALLENGE THEN TURNS TO HOW QUICKLY THE LOWER CLOUD BASE
ERODES. HRRR AND RAP GUIDANCE ARE A BIT MIXED TO HOW QUICKLY THIS
OCCURS. THE GENERAL FEELING IS THAT SOMETIME THIS EVENING THE MVFR
DECK WILL LIFT ABOVE 2000 FT AND SCATTER OUT AS THE HRRR
SUGGESTS...BUT CONFIDENCE ON THIS TIMING IS MEDIUM. HIGHEST CONFIDENCE
ON TIMING THIS OCCURRENCE IS AT KCMI AND EASTERN LOCATIONS WHERE
DRIER AIR WILL MORE READILY ADVECT IN. MEANWHILE THE RAP AND NAM
HOLD ONTO THE CLOUDS THROUGH 6Z OR SLIGHTLY LATER AS A LOW LEVEL
INVERSION REMAINS IN PLACE. WINDS OVERNIGHT WILL VEER TO THE
SOUTHEAST AND WEAKEN BEFORE STRENGTHENING TOMORROW MORNING. SOME
PATCHY FOG MAY DEVELOP AFTER CLOUDS CLEAR BUT HELD OFF ANY MENTION
AT THIS POINT.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...kmd
LONG TERM...07
AVIATION...KMD
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
146 PM CST TUE JAN 27 2015
.SHORT TERM...
330 AM CST
THROUGH WEDNESDAY...
INFRARED AND WATER VAPOR SATELLITE LOOPS EARLY THIS MORNING HAVE
SHOWN THE LAST IN A SERIES OF SHEARED VORTICITY MAXIMA TO HAVE MOVED
SOUTHEAST OF THE AREA. LIGHT SNOW ASSOCIATED WITH THESE HAS MAINLY
ENDED. LOW-LEVEL WINDS HAVE ALSO SHIFTED MORE NORTHERLY AS A
SURFACE INDUCED TROUGH AXIS PULLS AWAY. THIS HAS ENDED THE LOW-
LEVEL ISENTROPIC ASCENT AND OMEGA WHICH HELPED TO INDUCE MUCH OF
THE FREEZING DRIZZLE LAST NIGHT. SO WITH THAT HAVE CANCELLED THE
ADVISORY AS THE WIDESPREAD THREAT HAS ENDED GOING INTO THE RUSH
HOUR. ONE HOPEFULLY ONLY SMALL FLY IN THE OINTMENT TO THIS IS THE
CHANCE FOR FREEZING DRIZZLE LINGERING IN MAINLY LAKE AND COOK
COUNTIES...INCLUDING CHICAGO...AS WINDS TURN OFF THE LAKE EARLY
THIS MORNING STEERING IN SOME MARGINAL LAKE-INDUCED INSTABILITY.
THE MKX RADAR IS INDICATING LIGHT ECHOES MOVING WESTWARD THAT
DUAL-POL SUGGESTS IS FREEZING DRIZZLE. RAP PROFILES ARE ONLY
SATURATED ABOUT AS COOL AS -8C ADDING SUPPORT TO THAT. WITH NOT
EXPECTING A SITUATION SUCH AS LAST EVENING GIVEN THE TREATMENT ON
ROADS AND THE DIFFERENT MORE MESOSCALE/LOCALIZED INDUCED
LIFT...FEEL BETTER GOING WITH AN SPS IF NEEDED. EXPECT THE CHANCES
TO END BY 10 AM OR SO AS DRIER AIR CONTINUES TO ADVECT WESTWARD
OVER THE LAKE SEEN BY DEW POINTS NEAR 10F ON THE MICHIGAN SHORE
ALONG WITH AN EAST WIND.
CLOUDS SHOULD BE SLOW TO CLEAR TODAY GIVEN THE CURRENT EXPANSIVENESS
TO THE NORTH AND THE CYCLONIC FLOW CONTINUING THROUGH THIS
MORNING...AS WELL AS AFOREMENTIONED LAKE-ORIENTED FLOW INTO
NORTHEAST ILLINOIS. MESOSCALE MODEL MOISTURE/CONDENSATE FIELDS
INDICATE CLOUDS LINGERING THE LONGEST ACROSS THE ILLINOIS PART OF
THE CWA WITH INDIANA EXPERIENCING NORTHEASTERLY DRY ADVECTION.
HAVE HIGHS ONLY A FEW DEGREES WARMER THAN CURRENT EARLY MORNING
VALUES GIVEN THIS THOUGHT PROCESS. CONFIDENCE IS LOW ON WHETHER
CLEARING OCCURS AREAWIDE LATE THIS AFTERNOON AND EVENING AS
GUIDANCE WOULD SUGGEST...PLUS THERE WILL LIKELY BE CIRRUS
SPREADING IN TOO. THIS INTRODUCES BUST POTENTIAL IN LOW
TEMPERATURES OVER NORTH CENTRAL ILLINOIS WHERE LOW TEENS TO MID
20S COULD OCCUR DEPENDING ON CLOUDS. FEEL MORE CONFIDENT NORTHWEST
INDIANA WILL BE MOSTLY CLEAR AND TOUCH SOME OF THOSE LOWER TO MID
TEENS.
DURING THE DAY WEDNESDAY...A THERMAL RIDGE BUILDS INTO THE AREA AND
EXPECTING AT LEAST SOME SUNSHINE AS SOUTHWESTERLY LOW-LEVEL FLOW
WILL BE ENOUGH TO ADVECT OUT ANY RESIDUAL LOW CLOUDS. THE WARMEST
PART OF THE THERMAL RIDGE REACHES US MORE SO WEDNESDAY NIGHT AND
CLIMATOLOGY FOR FORECAST 925MB TEMPERATURES WOULD KEEP
SURFACE READINGS IN THE 30S FOR MOST OF THE CWA ESPECIALLY WITH
SOME SNOW COVER ALBEIT MINIMAL.
MTF
&&
.LONG TERM...
330 AM CST
WEDNESDAY NIGHT THROUGH MONDAY...
THE NEXT CHANCE FOR PRECIPITATION IS WEDNESDAY NIGHT AND
THURSDAY...AND CONFIDENCE HAS FURTHER INCREASED THAT THIS WILL BE A
LIGHT PRECIPITATION EVENT...AS WELL AS ONE WITH ONLY LIQUID
WEDNESDAY NIGHT IF PRECIPITATION DEVELOPS OVER OUR AREA. A CLOSED
UPPER LOW NEAR LOS ANGELES EARLY THIS MORNING IS STILL FORECAST TO
GET CAUGHT IN THE WESTERLIES AND DAMPEN THE STRONG UPPER RIDGE IN
PLACE OVER THE ROCKIES. A GRADUAL PHASING WITH A NORTHERN STREAM
PROGRESSIVE WAVE IS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY
OVER THE GREAT LAKES REGION. WHILE THE 27.00 GFS IS MORE
AGGRESSIVE WITH THIS PHASING THAN OTHER 27.00 GUIDANCE...IT ONLY
BRINGS A LITTLE MORE OOMPH FOR PRECIP HERE. THE THERMAL RIDGE
MENTIONED IN THE SHORT TERM SECTION FOR WEDNESDAY IS 2C-6C AT
850-925MB AND SURFACE TEMPERATURES ARE NOT LIKELY TO DROP GIVEN
THE SOUTHERN FLOW AND INCREASING CLOUDS...SO HAVE CHANCES OF RAIN
AND DRIZZLE WEDNESDAY NIGHT AS MOISTURE TRANSPORT DEVELOPS. ON
THURSDAY...TRANSITION TO A LIGHT RAIN AND SNOW MIX AND AT THIS
POINT WPC AND OURSELVES REALLY HAVE NO ACCUMULATIONS FORECAST.
HAVE STILL TRIED TO TAKE INTO ACCOUNT SOME POSSIBLE SLOWING IN THE
FORECAST GIVEN THE CURRENT SIGNIFICANT CLOSED SYSTEM OFF THE
NORTHEAST U.S...AND KEPT PRECIP CHANCES INTO THURSDAY AFTERNOON.
THE PROGRESSIVE ACTIVE FLOW PATTERN IS FORECAST TO CONTINUE INTO
THE WEEKEND...WITH STRONG HIGH PRESSURE ON FRIDAY GIVING WAY TO
PRECIPITATION CHANCES THIS WEEKEND. ANOTHER CLOSED LOW OVER THE
FAR SOUTHWESTERN U.S. IS FORECAST TO MOVE GRADUALLY EASTWARD AND
LOOKS TO BE ABLE TO TAP INTO GULF AND EASTERN PACIFIC MOISTURE.
WITH A CUT-OFF FEATURE THIS COULD END UP SLOWING AND CERTAINLY
CHANGING IN EVOLUTION. GUIDANCE DISAGREES HOW ANY NORTHERN STREAM
DISTURBANCE MAY AID TO PULL SOME OF THIS MOISTURE OVER OUR AREA.
AT THIS TIME THIS LOOKS TO BE A POSSIBLY LONG DURATION BUT LIGHT
INTENSITY QPF EVENT AT THIS LATITUDE. GIVEN THE FEATURES AT PLAY
AND CURRENT PATTERN WE ARE IN...ITS JUST WAY TOO EARLY AS
POTENTIAL COULD GO EITHER WAY FROM THAT SOLUTION. CONFIDENCE IS A
LITTLE HIGHER IN THAT IT WOULD PROBABLY BE A MAINLY SNOW EVENT IF
IT WERE TO OCCUR. GUIDANCE IS IN BETTER AGREEMENT THAN 24 HOURS
AGO WITH A CANADIAN/MODIFIED ARCTIC AIR MASS BEING TAPPED IN THE
WAKE OF THIS SYSTEM WITH POSSIBLY SINGLE DIGIT NIGHTTIME
TEMPERATURES DEPENDING ON IF ANY FRESH SNOW COVER CAN OCCUR.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS CLEARING THE TERMINALS EARLY THIS AFTERNOON...BUT
LIKELY REMAIN NEARBY THIS EVENING AND TONIGHT.
BMD
//DISCUSSION...UPDATED 18Z...
BROAD MVFR STRATUS DECK BLANKETS THE REGION TODAY BUT HAS BEEN
STEADILY ERODING FROM THE NORTHEAST...WITH CLEARING SKIES MAKING
PROGRESS DOWN LAKE MICHIGAN THIS MORNING AND INTO THE CHICAGO AREA
EARLY THIS AFTERNOON. CLOUD BEARING FLOW OUT OF THE NORTHEAST THIS
MORNING WILL BACK TO THE NORTH THIS AFTERNOON AND EVENING SO EXPECT
THE PROGRESS OF THE CLEARING TO SLOW SOME...AND MAY EVEN REVERSE
TONIGHT AS A SURFACE RIDGE BUILDS ACROSS INDIANA WITH FLOW BECOMING
MORE SOUTHERLY. SURFACE WINDS WILL GENERALLY DECREASE FROM MID
AFTERNOON ON AS THE SURFACE HIGH NEARS...AND GO LIGHT AND
VARIABLE FOR A PERIOD THIS EVENING AND OVERNIGHT...BEFORE TURNING
SOUTH/SOUTH-SOUTHEAST TOMORROW. GUSTY WINDS PUSHING 20 KT ARE
EXPECTED TOMORROW AFTERNOON.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN PERIODS OF VFR THIS AFTERNOON...LOW-MEDIUM
CONFIDENCE IN CIG TRENDS OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...CHANCE OF RAIN/DRIZZLE. MVFR/IFR POSSIBLE.
THURSDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY/IFR POSSIBLE.
FRIDAY AND SATURDAY...PRIMARILY VFR. CHANCE OF SNOW SATURDAY
NIGHT.
SUNDAY...CHANCE OF LIGHT SNOW. IFR POSSIBLE.
MONDAY...MVFR CIGS POSSIBLE.
RATZER
&&
.MARINE...
213 AM CST
MARINE CONCERNS ON LAKE MICHIGAN ARE A PERIOD OF STRONG SOUTH WINDS
WEDNESDAY AFTERNOON AND NIGHT...THEN A SHIFT TO STRONG NORTH TO
NORTHWEST WINDS THURSDAY AFTERNOON INTO EARLY FRIDAY...WITH THE
POTENTIAL FOR A PERIOD OF NORTHWEST GALES ESPECIALLY THURSDAY
AFTERNOON AND THURSDAY EVENING.
IN THE NEAR TERM...RELATIVELY QUIET WEATHER ACROSS THE LAKE EARLY
THIS MORNING AS A WEAKENING SURFACE TROUGH OVER ILLINOIS AND THE
LOWER OHIO VALLEY CONTINUES TO MOVE OFF TO THE SOUTHEAST...ALLOWING
WEAK HIGH PRESSURE TO SETTLE ACROSS THE AREA FROM THE NORTH TODAY.
LOOKING TO THE WEST...AN AREA OF LOW PRESSURE DEVELOPING IN THE LEE
OF THE CANADIAN ROCKIES WILL SLIDE SOUTHEAST INTO THE PLAINS
THROUGH TONIGHT...THEN WILL MOVE SLOWLY EAST TOWARD LAKE MICHIGAN
WEDNESDAY AND WEDNESDAY NIGHT. IN RESPONSE TO PRESSURE FALLS AHEAD
OF THE LOW...THE GRADIENT WILL TIGHTEN ACROSS LAKE MICHIGAN
WEDNESDAY WITH SOUTH WINDS RAMPING UP INTO THE 30 KT RANGE BY LATE
AFTERNOON AND EVENING. WINDS WILL DIMINISH BRIEFLY EARLY THURSDAY
MORNING AS THE LOW PRESSURE CENTER AND COLD FRONTAL TROUGH CROSS THE
LAKE...BEFORE WINDS SHIFT TO THE NORTH-NORTHWEST AND INCREASE
QUICKLY BACK INTO THE 30-35 KT RANGE THURSDAY AFTERNOON. FORECAST
SOUNDINGS INDICATE THE POTENTIAL FOR GALES THURSDAY AFTERNOON AND
EVENING IN THE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND THE
DEPARTING LOW AND COLD FRONT. THESE STRONG WINDS WILL CONTINUE INTO
EARLY FRIDAY...BEFORE DIMINISHING AS A BROAD AREA OF HIGH PRESSURE
SPREADS INTO THE AREA BY FRIDAY EVENING. THE HIGH WILL SLOWLY MOVE
OFF TO THE EAST ON SATURDAY...WITH A WEAK LOW EXPECTED TO PASS
ACROSS THE NORTHERN LAKES SATURDAY NIGHT AND TRAIL A COLD FRONT
ACROSS LAKE MICHIGAN THROUGH SUNDAY.
FOR THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE WATERS SMALL CRAFT
ADVISORY CONDITIONS LOOK TO DEVELOP WEDNESDAY AFTERNOON AND CONTINUE
THROUGH THURSDAY MORNING...WITH A BRIEF BREAK BEFORE HIGH WIND/WAVE
CONDITIONS DEVELOP AGAIN BY EARLY THURSDAY AFTERNOON. HIGH WAVES
WOULD LIKELY LINGER THROUGH MUCH OF FRIDAY...ESPECIALLY ALONG THE
INDIANA SHORE EAST OF GARY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1146 AM CST TUE JAN 27 2015
.SHORT TERM...
330 AM CST
THROUGH WEDNESDAY...
INFRARED AND WATER VAPOR SATELLITE LOOPS EARLY THIS MORNING HAVE
SHOWN THE LAST IN A SERIES OF SHEARED VORTICITY MAXIMA TO HAVE MOVED
SOUTHEAST OF THE AREA. LIGHT SNOW ASSOCIATED WITH THESE HAS MAINLY
ENDED. LOW-LEVEL WINDS HAVE ALSO SHIFTED MORE NORTHERLY AS A
SURFACE INDUCED TROUGH AXIS PULLS AWAY. THIS HAS ENDED THE LOW-
LEVEL ISENTROPIC ASCENT AND OMEGA WHICH HELPED TO INDUCE MUCH OF
THE FREEZING DRIZZLE LAST NIGHT. SO WITH THAT HAVE CANCELLED THE
ADVISORY AS THE WIDESPREAD THREAT HAS ENDED GOING INTO THE RUSH
HOUR. ONE HOPEFULLY ONLY SMALL FLY IN THE OINTMENT TO THIS IS THE
CHANCE FOR FREEZING DRIZZLE LINGERING IN MAINLY LAKE AND COOK
COUNTIES...INCLUDING CHICAGO...AS WINDS TURN OFF THE LAKE EARLY
THIS MORNING STEERING IN SOME MARGINAL LAKE-INDUCED INSTABILITY.
THE MKX RADAR IS INDICATING LIGHT ECHOES MOVING WESTWARD THAT
DUAL-POL SUGGESTS IS FREEZING DRIZZLE. RAP PROFILES ARE ONLY
SATURATED ABOUT AS COOL AS -8C ADDING SUPPORT TO THAT. WITH NOT
EXPECTING A SITUATION SUCH AS LAST EVENING GIVEN THE TREATMENT ON
ROADS AND THE DIFFERENT MORE MESOSCALE/LOCALIZED INDUCED
LIFT...FEEL BETTER GOING WITH AN SPS IF NEEDED. EXPECT THE CHANCES
TO END BY 10 AM OR SO AS DRIER AIR CONTINUES TO ADVECT WESTWARD
OVER THE LAKE SEEN BY DEW POINTS NEAR 10F ON THE MICHIGAN SHORE
ALONG WITH AN EAST WIND.
CLOUDS SHOULD BE SLOW TO CLEAR TODAY GIVEN THE CURRENT EXPANSIVENESS
TO THE NORTH AND THE CYCLONIC FLOW CONTINUING THROUGH THIS
MORNING...AS WELL AS AFOREMENTIONED LAKE-ORIENTED FLOW INTO
NORTHEAST ILLINOIS. MESOSCALE MODEL MOISTURE/CONDENSATE FIELDS
INDICATE CLOUDS LINGERING THE LONGEST ACROSS THE ILLINOIS PART OF
THE CWA WITH INDIANA EXPERIENCING NORTHEASTERLY DRY ADVECTION.
HAVE HIGHS ONLY A FEW DEGREES WARMER THAN CURRENT EARLY MORNING
VALUES GIVEN THIS THOUGHT PROCESS. CONFIDENCE IS LOW ON WHETHER
CLEARING OCCURS AREAWIDE LATE THIS AFTERNOON AND EVENING AS
GUIDANCE WOULD SUGGEST...PLUS THERE WILL LIKELY BE CIRRUS
SPREADING IN TOO. THIS INTRODUCES BUST POTENTIAL IN LOW
TEMPERATURES OVER NORTH CENTRAL ILLINOIS WHERE LOW TEENS TO MID
20S COULD OCCUR DEPENDING ON CLOUDS. FEEL MORE CONFIDENT NORTHWEST
INDIANA WILL BE MOSTLY CLEAR AND TOUCH SOME OF THOSE LOWER TO MID
TEENS.
DURING THE DAY WEDNESDAY...A THERMAL RIDGE BUILDS INTO THE AREA AND
EXPECTING AT LEAST SOME SUNSHINE AS SOUTHWESTERLY LOW-LEVEL FLOW
WILL BE ENOUGH TO ADVECT OUT ANY RESIDUAL LOW CLOUDS. THE WARMEST
PART OF THE THERMAL RIDGE REACHES US MORE SO WEDNESDAY NIGHT AND
CLIMATOLOGY FOR FORECAST 925MB TEMPERATURES WOULD KEEP
SURFACE READINGS IN THE 30S FOR MOST OF THE CWA ESPECIALLY WITH
SOME SNOW COVER ALBEIT MINIMAL.
MTF
&&
.LONG TERM...
330 AM CST
WEDNESDAY NIGHT THROUGH MONDAY...
THE NEXT CHANCE FOR PRECIPITATION IS WEDNESDAY NIGHT AND
THURSDAY...AND CONFIDENCE HAS FURTHER INCREASED THAT THIS WILL BE A
LIGHT PRECIPITATION EVENT...AS WELL AS ONE WITH ONLY LIQUID
WEDNESDAY NIGHT IF PRECIPITATION DEVELOPS OVER OUR AREA. A CLOSED
UPPER LOW NEAR LOS ANGELES EARLY THIS MORNING IS STILL FORECAST TO
GET CAUGHT IN THE WESTERLIES AND DAMPEN THE STRONG UPPER RIDGE IN
PLACE OVER THE ROCKIES. A GRADUAL PHASING WITH A NORTHERN STREAM
PROGRESSIVE WAVE IS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY
OVER THE GREAT LAKES REGION. WHILE THE 27.00 GFS IS MORE
AGGRESSIVE WITH THIS PHASING THAN OTHER 27.00 GUIDANCE...IT ONLY
BRINGS A LITTLE MORE OOMPH FOR PRECIP HERE. THE THERMAL RIDGE
MENTIONED IN THE SHORT TERM SECTION FOR WEDNESDAY IS 2C-6C AT
850-925MB AND SURFACE TEMPERATURES ARE NOT LIKELY TO DROP GIVEN
THE SOUTHERN FLOW AND INCREASING CLOUDS...SO HAVE CHANCES OF RAIN
AND DRIZZLE WEDNESDAY NIGHT AS MOISTURE TRANSPORT DEVELOPS. ON
THURSDAY...TRANSITION TO A LIGHT RAIN AND SNOW MIX AND AT THIS
POINT WPC AND OURSELVES REALLY HAVE NO ACCUMULATIONS FORECAST.
HAVE STILL TRIED TO TAKE INTO ACCOUNT SOME POSSIBLE SLOWING IN THE
FORECAST GIVEN THE CURRENT SIGNIFICANT CLOSED SYSTEM OFF THE
NORTHEAST U.S...AND KEPT PRECIP CHANCES INTO THURSDAY AFTERNOON.
THE PROGRESSIVE ACTIVE FLOW PATTERN IS FORECAST TO CONTINUE INTO
THE WEEKEND...WITH STRONG HIGH PRESSURE ON FRIDAY GIVING WAY TO
PRECIPITATION CHANCES THIS WEEKEND. ANOTHER CLOSED LOW OVER THE
FAR SOUTHWESTERN U.S. IS FORECAST TO MOVE GRADUALLY EASTWARD AND
LOOKS TO BE ABLE TO TAP INTO GULF AND EASTERN PACIFIC MOISTURE.
WITH A CUT-OFF FEATURE THIS COULD END UP SLOWING AND CERTAINLY
CHANGING IN EVOLUTION. GUIDANCE DISAGREES HOW ANY NORTHERN STREAM
DISTURBANCE MAY AID TO PULL SOME OF THIS MOISTURE OVER OUR AREA.
AT THIS TIME THIS LOOKS TO BE A POSSIBLY LONG DURATION BUT LIGHT
INTENSITY QPF EVENT AT THIS LATITUDE. GIVEN THE FEATURES AT PLAY
AND CURRENT PATTERN WE ARE IN...ITS JUST WAY TOO EARLY AS
POTENTIAL COULD GO EITHER WAY FROM THAT SOLUTION. CONFIDENCE IS A
LITTLE HIGHER IN THAT IT WOULD PROBABLY BE A MAINLY SNOW EVENT IF
IT WERE TO OCCUR. GUIDANCE IS IN BETTER AGREEMENT THAN 24 HOURS
AGO WITH A CANADIAN/MODIFIED ARCTIC AIR MASS BEING TAPPED IN THE
WAKE OF THIS SYSTEM WITH POSSIBLY SINGLE DIGIT NIGHTTIME
TEMPERATURES DEPENDING ON IF ANY FRESH SNOW COVER CAN OCCUR.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* MVFR CIGS CLEARING THE TERMINALS EARLY THIS AFTERNOON...BUT
LIKELY REMAIN NEARBY THIS EVENING AND TONIGHT.
BMD
//DISCUSSION...UPDATED 18Z...
BROAD MVFR STRATUS DECK BLANKETS THE REGION TODAY BUT HAS BEEN
STEADILY ERODING FROM THE NORTHEAST...WITH CLEARING SKIES MAKING
PROGRESS DOWN LAKE MICHIGAN THIS MORNING AND INTO THE CHICAGO AREA
EARLY THIS AFTERNOON. CLOUD BEARING FLOW OUT OF THE NORTHEAST THIS
MORNING WILL BACK TO THE NORTH THIS AFTERNOON AND EVENING SO EXPECT
THE PROGRESS OF THE CLEARING TO SLOW SOME...AND MAY EVEN REVERSE
TONIGHT AS A SURFACE RIDGE BUILDS ACROSS INDIANA WITH FLOW BECOMING
MORE SOUTHERLY. SURFACE WINDS WILL GENERALLY DECREASE FROM MID
AFTERNOON ON AS THE SURFACE HIGH NEARS...AND GO LIGHT AND
VARIABLE FOR A PERIOD THIS EVENING AND OVERNIGHT...BEFORE TURNING
SOUTH/SOUTH-SOUTHEAST TOMORROW. GUSTY WINDS PUSHING 20 KT ARE
EXPECTED TOMORROW AFTERNOON.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH CONFIDENCE IN PERIODS OF VFR THIS AFTERNOON...LOW-
MEDIUM CONFIDENCE IN CIG TRENDS OVERNIGHT.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...CHANCE OF RAIN/DRIZZLE. MVFR/IFR POSSIBLE.
THURSDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY/IFR POSSIBLE.
FRIDAY AND SATURDAY...PRIMARILY VFR. CHANCE OF SNOW SATURDAY
NIGHT.
SUNDAY...CHANCE OF LIGHT SNOW. IFR POSSIBLE.
MONDAY...MVFR CIGS POSSIBLE.
RATZER
&&
.MARINE...
213 AM CST
MARINE CONCERNS ON LAKE MICHIGAN ARE A PERIOD OF STRONG SOUTH WINDS
WEDNESDAY AFTERNOON AND NIGHT...THEN A SHIFT TO STRONG NORTH TO
NORTHWEST WINDS THURSDAY AFTERNOON INTO EARLY FRIDAY...WITH THE
POTENTIAL FOR A PERIOD OF NORTHWEST GALES ESPECIALLY THURSDAY
AFTERNOON AND THURSDAY EVENING.
IN THE NEAR TERM...RELATIVELY QUIET WEATHER ACROSS THE LAKE EARLY
THIS MORNING AS A WEAKENING SURFACE TROUGH OVER ILLINOIS AND THE
LOWER OHIO VALLEY CONTINUES TO MOVE OFF TO THE SOUTHEAST...ALLOWING
WEAK HIGH PRESSURE TO SETTLE ACROSS THE AREA FROM THE NORTH TODAY.
LOOKING TO THE WEST...AN AREA OF LOW PRESSURE DEVELOPING IN THE LEE
OF THE CANADIAN ROCKIES WILL SLIDE SOUTHEAST INTO THE PLAINS
THROUGH TONIGHT...THEN WILL MOVE SLOWLY EAST TOWARD LAKE MICHIGAN
WEDNESDAY AND WEDNESDAY NIGHT. IN RESPONSE TO PRESSURE FALLS AHEAD
OF THE LOW...THE GRADIENT WILL TIGHTEN ACROSS LAKE MICHIGAN
WEDNESDAY WITH SOUTH WINDS RAMPING UP INTO THE 30 KT RANGE BY LATE
AFTERNOON AND EVENING. WINDS WILL DIMINISH BRIEFLY EARLY THURSDAY
MORNING AS THE LOW PRESSURE CENTER AND COLD FRONTAL TROUGH CROSS THE
LAKE...BEFORE WINDS SHIFT TO THE NORTH-NORTHWEST AND INCREASE
QUICKLY BACK INTO THE 30-35 KT RANGE THURSDAY AFTERNOON. FORECAST
SOUNDINGS INDICATE THE POTENTIAL FOR GALES THURSDAY AFTERNOON AND
EVENING IN THE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND THE
DEPARTING LOW AND COLD FRONT. THESE STRONG WINDS WILL CONTINUE INTO
EARLY FRIDAY...BEFORE DIMINISHING AS A BROAD AREA OF HIGH PRESSURE
SPREADS INTO THE AREA BY FRIDAY EVENING. THE HIGH WILL SLOWLY MOVE
OFF TO THE EAST ON SATURDAY...WITH A WEAK LOW EXPECTED TO PASS
ACROSS THE NORTHERN LAKES SATURDAY NIGHT AND TRAIL A COLD FRONT
ACROSS LAKE MICHIGAN THROUGH SUNDAY.
FOR THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE WATERS SMALL CRAFT
ADVISORY CONDITIONS LOOK TO DEVELOP WEDNESDAY AFTERNOON AND CONTINUE
THROUGH THURSDAY MORNING...WITH A BRIEF BREAK BEFORE HIGH WIND/WAVE
CONDITIONS DEVELOP AGAIN BY EARLY THURSDAY AFTERNOON. HIGH WAVES
WOULD LIKELY LINGER THROUGH MUCH OF FRIDAY...ESPECIALLY ALONG THE
INDIANA SHORE EAST OF GARY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1016 AM CST TUE JAN 27 2015
.SHORT TERM...
330 AM CST
THROUGH WEDNESDAY...
INFRARED AND WATER VAPOR SATELLITE LOOPS EARLY THIS MORNING HAVE
SHOWN THE LAST IN A SERIES OF SHEARED VORTICITY MAXIMA TO HAVE MOVED
SOUTHEAST OF THE AREA. LIGHT SNOW ASSOCIATED WITH THESE HAS MAINLY
ENDED. LOW-LEVEL WINDS HAVE ALSO SHIFTED MORE NORTHERLY AS A
SURFACE INDUCED TROUGH AXIS PULLS AWAY. THIS HAS ENDED THE LOW-
LEVEL ISENTROPIC ASCENT AND OMEGA WHICH HELPED TO INDUCE MUCH OF
THE FREEZING DRIZZLE LAST NIGHT. SO WITH THAT HAVE CANCELLED THE
ADVISORY AS THE WIDESPREAD THREAT HAS ENDED GOING INTO THE RUSH
HOUR. ONE HOPEFULLY ONLY SMALL FLY IN THE OINTMENT TO THIS IS THE
CHANCE FOR FREEZING DRIZZLE LINGERING IN MAINLY LAKE AND COOK
COUNTIES...INCLUDING CHICAGO...AS WINDS TURN OFF THE LAKE EARLY
THIS MORNING STEERING IN SOME MARGINAL LAKE-INDUCED INSTABILITY.
THE MKX RADAR IS INDICATING LIGHT ECHOES MOVING WESTWARD THAT
DUAL-POL SUGGESTS IS FREEZING DRIZZLE. RAP PROFILES ARE ONLY
SATURATED ABOUT AS COOL AS -8C ADDING SUPPORT TO THAT. WITH NOT
EXPECTING A SITUATION SUCH AS LAST EVENING GIVEN THE TREATMENT ON
ROADS AND THE DIFFERENT MORE MESOSCALE/LOCALIZED INDUCED
LIFT...FEEL BETTER GOING WITH AN SPS IF NEEDED. EXPECT THE CHANCES
TO END BY 10 AM OR SO AS DRIER AIR CONTINUES TO ADVECT WESTWARD
OVER THE LAKE SEEN BY DEW POINTS NEAR 10F ON THE MICHIGAN SHORE
ALONG WITH AN EAST WIND.
CLOUDS SHOULD BE SLOW TO CLEAR TODAY GIVEN THE CURRENT EXPANSIVENESS
TO THE NORTH AND THE CYCLONIC FLOW CONTINUING THROUGH THIS
MORNING...AS WELL AS AFOREMENTIONED LAKE-ORIENTED FLOW INTO
NORTHEAST ILLINOIS. MESOSCALE MODEL MOISTURE/CONDENSATE FIELDS
INDICATE CLOUDS LINGERING THE LONGEST ACROSS THE ILLINOIS PART OF
THE CWA WITH INDIANA EXPERIENCING NORTHEASTERLY DRY ADVECTION.
HAVE HIGHS ONLY A FEW DEGREES WARMER THAN CURRENT EARLY MORNING
VALUES GIVEN THIS THOUGHT PROCESS. CONFIDENCE IS LOW ON WHETHER
CLEARING OCCURS AREAWIDE LATE THIS AFTERNOON AND EVENING AS
GUIDANCE WOULD SUGGEST...PLUS THERE WILL LIKELY BE CIRRUS
SPREADING IN TOO. THIS INTRODUCES BUST POTENTIAL IN LOW
TEMPERATURES OVER NORTH CENTRAL ILLINOIS WHERE LOW TEENS TO MID
20S COULD OCCUR DEPENDING ON CLOUDS. FEEL MORE CONFIDENT NORTHWEST
INDIANA WILL BE MOSTLY CLEAR AND TOUCH SOME OF THOSE LOWER TO MID
TEENS.
DURING THE DAY WEDNESDAY...A THERMAL RIDGE BUILDS INTO THE AREA AND
EXPECTING AT LEAST SOME SUNSHINE AS SOUTHWESTERLY LOW-LEVEL FLOW
WILL BE ENOUGH TO ADVECT OUT ANY RESIDUAL LOW CLOUDS. THE WARMEST
PART OF THE THERMAL RIDGE REACHES US MORE SO WEDNESDAY NIGHT AND
CLIMATOLOGY FOR FORECAST 925MB TEMPERATURES WOULD KEEP
SURFACE READINGS IN THE 30S FOR MOST OF THE CWA ESPECIALLY WITH
SOME SNOW COVER ALBEIT MINIMAL.
MTF
&&
.LONG TERM...
330 AM CST
WEDNESDAY NIGHT THROUGH MONDAY...
THE NEXT CHANCE FOR PRECIPITATION IS WEDNESDAY NIGHT AND
THURSDAY...AND CONFIDENCE HAS FURTHER INCREASED THAT THIS WILL BE A
LIGHT PRECIPITATION EVENT...AS WELL AS ONE WITH ONLY LIQUID
WEDNESDAY NIGHT IF PRECIPITATION DEVELOPS OVER OUR AREA. A CLOSED
UPPER LOW NEAR LOS ANGELES EARLY THIS MORNING IS STILL FORECAST TO
GET CAUGHT IN THE WESTERLIES AND DAMPEN THE STRONG UPPER RIDGE IN
PLACE OVER THE ROCKIES. A GRADUAL PHASING WITH A NORTHERN STREAM
PROGRESSIVE WAVE IS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY
OVER THE GREAT LAKES REGION. WHILE THE 27.00 GFS IS MORE
AGGRESSIVE WITH THIS PHASING THAN OTHER 27.00 GUIDANCE...IT ONLY
BRINGS A LITTLE MORE OOMPH FOR PRECIP HERE. THE THERMAL RIDGE
MENTIONED IN THE SHORT TERM SECTION FOR WEDNESDAY IS 2C-6C AT
850-925MB AND SURFACE TEMPERATURES ARE NOT LIKELY TO DROP GIVEN
THE SOUTHERN FLOW AND INCREASING CLOUDS...SO HAVE CHANCES OF RAIN
AND DRIZZLE WEDNESDAY NIGHT AS MOISTURE TRANSPORT DEVELOPS. ON
THURSDAY...TRANSITION TO A LIGHT RAIN AND SNOW MIX AND AT THIS
POINT WPC AND OURSELVES REALLY HAVE NO ACCUMULATIONS FORECAST.
HAVE STILL TRIED TO TAKE INTO ACCOUNT SOME POSSIBLE SLOWING IN THE
FORECAST GIVEN THE CURRENT SIGNIFICANT CLOSED SYSTEM OFF THE
NORTHEAST U.S...AND KEPT PRECIP CHANCES INTO THURSDAY AFTERNOON.
THE PROGRESSIVE ACTIVE FLOW PATTERN IS FORECAST TO CONTINUE INTO
THE WEEKEND...WITH STRONG HIGH PRESSURE ON FRIDAY GIVING WAY TO
PRECIPITATION CHANCES THIS WEEKEND. ANOTHER CLOSED LOW OVER THE
FAR SOUTHWESTERN U.S. IS FORECAST TO MOVE GRADUALLY EASTWARD AND
LOOKS TO BE ABLE TO TAP INTO GULF AND EASTERN PACIFIC MOISTURE.
WITH A CUT-OFF FEATURE THIS COULD END UP SLOWING AND CERTAINLY
CHANGING IN EVOLUTION. GUIDANCE DISAGREES HOW ANY NORTHERN STREAM
DISTURBANCE MAY AID TO PULL SOME OF THIS MOISTURE OVER OUR AREA.
AT THIS TIME THIS LOOKS TO BE A POSSIBLY LONG DURATION BUT LIGHT
INTENSITY QPF EVENT AT THIS LATITUDE. GIVEN THE FEATURES AT PLAY
AND CURRENT PATTERN WE ARE IN...ITS JUST WAY TOO EARLY AS
POTENTIAL COULD GO EITHER WAY FROM THAT SOLUTION. CONFIDENCE IS A
LITTLE HIGHER IN THAT IT WOULD PROBABLY BE A MAINLY SNOW EVENT IF
IT WERE TO OCCUR. GUIDANCE IS IN BETTER AGREEMENT THAN 24 HOURS
AGO WITH A CANADIAN/MODIFIED ARCTIC AIR MASS BEING TAPPED IN THE
WAKE OF THIS SYSTEM WITH POSSIBLY SINGLE DIGIT NIGHTTIME
TEMPERATURES DEPENDING ON IF ANY FRESH SNOW COVER CAN OCCUR.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CIGS SCATTERING TO VFR LATER THIS MORNING OR EARLY AFTERNOON.
* NORTHEAST WINDS AROUND 10 KT TODAY...BECOMING LIGHT/VARIABLE
AGAIN THIS EVENING/OVERNIGHT.
RATZER/DEUBELBEISS
//DISCUSSION...UPDATED 12Z...
WEAK LOW PRESSURE SYSTEM CONTINUES TO PULL AWAY TO THE SOUTHEAST
THIS MORNING...WITH A LINGERING SURFACE TROUGH REMAINING THE FOCUS
FOR AN AREA OF LOW CLOUDS...MVFR FOG AND SOME PATCHY LIGHT
FREEZING DRIZZLE. MID-LEVEL DISTURBANCE OVERHEAD AND WILL MOVE OFF
TO THE SOUTHEAST THIS MORNING...WHICH ALONG WITH DRIER NORTHEAST
WINDS DEVELOPING ABOVE THE SURFACE SHOULD LEAD TO DIMINISHING
POTENTIAL FOR -FZDZ BY MID-MORNING. DRIER AIR FROM THE NORTHEAST
SHOULD ALSO WORK TO RAISE CIGS AND IMPROVE VIS THROUGH THE MORNING
AND EARLY AFTERNOON HOURS AS WELL. WEAK HIGH PRESSURE WILL SPREAD
ACROSS THE AREA FROM THE NORTHWEST THIS EVENING...WITH VFR
CONDITIONS...THOUGH RFD/DPA COULD SEE SOME SHALLOW FOG DEVELOP
OVERNIGHT.
NORTH-NORTHEAST WINDS EARLY THIS MORNING WILL BECOME MORE SOLIDLY
NORTHEAST DURING THE MORNING...AROUND 10 KT. WINDS WILL DIMINISH
TOWARD EVENING AS GRADIENT WEAKENS WITH APPROACH OF THE HIGH...
WITH LIGHT/VARIABLE WINDS THIS EVENING AND OVERNIGHT. WITH THE
HIGH SHIFTING SOUTHEAST OF THE AREA EARLY WEDNESDAY...SOUTH WINDS
WILL DEVELOP.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM IN TIMING IMPROVEMENT FROM MVFR TO VFR.
* HIGH IN WIND TRENDS.
RATZER/DEUBELBEISS
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...CHANCE OF RAIN/DRIZZLE. MVFR/IFR POSSIBLE.
THURSDAY...CHANCE OF RAIN/SNOW. MVFR LIKELY/IFR POSSIBLE.
FRIDAY AND SATURDAY...PRIMARILY VFR. CHANCE OF SNOW SATURDAY
NIGHT.
SUNDAY...CHANCE OF LIGHT SNOW. IFR POSSIBLE.
MONDAY...MVFR CIGS POSSIBLE.
RATZER
&&
.MARINE...
213 AM CST
MARINE CONCERNS ON LAKE MICHIGAN ARE A PERIOD OF STRONG SOUTH WINDS
WEDNESDAY AFTERNOON AND NIGHT...THEN A SHIFT TO STRONG NORTH TO
NORTHWEST WINDS THURSDAY AFTERNOON INTO EARLY FRIDAY...WITH THE
POTENTIAL FOR A PERIOD OF NORTHWEST GALES ESPECIALLY THURSDAY
AFTERNOON AND THURSDAY EVENING.
IN THE NEAR TERM...RELATIVELY QUIET WEATHER ACROSS THE LAKE EARLY
THIS MORNING AS A WEAKENING SURFACE TROUGH OVER ILLINOIS AND THE
LOWER OHIO VALLEY CONTINUES TO MOVE OFF TO THE SOUTHEAST...ALLOWING
WEAK HIGH PRESSURE TO SETTLE ACROSS THE AREA FROM THE NORTH TODAY.
LOOKING TO THE WEST...AN AREA OF LOW PRESSURE DEVELOPING IN THE LEE
OF THE CANADIAN ROCKIES WILL SLIDE SOUTHEAST INTO THE PLAINS
THROUGH TONIGHT...THEN WILL MOVE SLOWLY EAST TOWARD LAKE MICHIGAN
WEDNESDAY AND WEDNESDAY NIGHT. IN RESPONSE TO PRESSURE FALLS AHEAD
OF THE LOW...THE GRADIENT WILL TIGHTEN ACROSS LAKE MICHIGAN
WEDNESDAY WITH SOUTH WINDS RAMPING UP INTO THE 30 KT RANGE BY LATE
AFTERNOON AND EVENING. WINDS WILL DIMINISH BRIEFLY EARLY THURSDAY
MORNING AS THE LOW PRESSURE CENTER AND COLD FRONTAL TROUGH CROSS THE
LAKE...BEFORE WINDS SHIFT TO THE NORTH-NORTHWEST AND INCREASE
QUICKLY BACK INTO THE 30-35 KT RANGE THURSDAY AFTERNOON. FORECAST
SOUNDINGS INDICATE THE POTENTIAL FOR GALES THURSDAY AFTERNOON AND
EVENING IN THE STRONG PRESSURE RISES AND COLD ADVECTION BEHIND THE
DEPARTING LOW AND COLD FRONT. THESE STRONG WINDS WILL CONTINUE INTO
EARLY FRIDAY...BEFORE DIMINISHING AS A BROAD AREA OF HIGH PRESSURE
SPREADS INTO THE AREA BY FRIDAY EVENING. THE HIGH WILL SLOWLY MOVE
OFF TO THE EAST ON SATURDAY...WITH A WEAK LOW EXPECTED TO PASS
ACROSS THE NORTHERN LAKES SATURDAY NIGHT AND TRAIL A COLD FRONT
ACROSS LAKE MICHIGAN THROUGH SUNDAY.
FOR THE ILLINOIS AND NORTHWEST INDIANA NEARSHORE WATERS SMALL CRAFT
ADVISORY CONDITIONS LOOK TO DEVELOP WEDNESDAY AFTERNOON AND CONTINUE
THROUGH THURSDAY MORNING...WITH A BRIEF BREAK BEFORE HIGH WIND/WAVE
CONDITIONS DEVELOP AGAIN BY EARLY THURSDAY AFTERNOON. HIGH WAVES
WOULD LIKELY LINGER THROUGH MUCH OF FRIDAY...ESPECIALLY ALONG THE
INDIANA SHORE EAST OF GARY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1239 PM EST TUE JAN 27 2015
.SYNOPSIS...
ISSUED AT 828 AM EST TUE JAN 27 2015
SKIES WILL CLEAR TODAY WITH TEMPERATURES WARMING INTO THE MID TO
UPPER 20S. TEMPERATURES WILL RISE TO NEAR FREEZING ON WEDNESDAY
WITH PARTLY CLOUDY SKIES. THE NEXT CHANCE OF PRECIPITATION WILL
ARRIVE WEDNESDAY NIGHT AND THURSDAY WITH A WINTRY MIX EXPECTED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM EST TUE JAN 27 2015
ANOTHER RELATIVELY QUIET SHORT TERM BUT CLOUD CONCERNS AND POSSIBLE
FZDZ THIS MORNING MAKE FOR A FEW ISSUES. FAR WESTERN CWA SATURATED
OVERNIGHT WITH FLURRIES OR VERY LIGHT SNOW FALLING IN DOWNSHEAR SIDE
OF MID LEVEL JET AXIS. ADVISORY ISSUED LAST EVENING FOR FREEZING
DRIZZLE THAT NEVER REALLY MATERIALIZED OVER OUR AREA DUE TO
SATURATED DGZ AND SEEDER FEEDER MECHANISMS ALLOWING FOR SNOW CRYSTAL
GROWTH. HOWEVER...STILL A SLIGHT CONCERN FOR LIGHT FZDZ THROUGH
SUNRISE AS SATELLITE SHOWS WARMING CLOUD TOPS UPSTREAM ACROSS WI
MOVING QUICKLY SOUTH AND LOSS OF HIGHER SEED CLOUDS EXPECTED NEXT
FEW HOURS. HIRES MODEL SOUNDINGS INDEED SHOWING DGZ DRYING OUT EARLY
THIS MORNING IN THE WEST BUT LOW LEVELS ALSO DRYING. THUS CHANCES
FOR ANY PCPN WILL BE DIMINISHING BUT PCPN TYPE OF ANY RESIDUAL PCPN
COULD BE FZDZ. CALLS TO WHITE AND PULASKI COUNTY INDICATE NO
PROBLEMS FROM FZDZ OVERNIGHT AND LITTLE TO NO REPORTS OF FZDZ
UPSTREAM AT THIS HOUR. WITH ADVISORY SET TO EXPIRE AT 6AM ANYWAY
PLAN TO CANCEL EARLY AND HANDLE ANY SPOTTY FREEZING LIQUID
DEVELOPMENT WITH SPECIAL WEATHER STATEMENTS IF NEEDED.
DRY WEDGE IN LOWER LEVELS HAS REMAINED IN PLACE ACROSS REMAINDER OF
CWA WITH LIGHT EASTERLY FLOW AIDING IN DRY AIR ENTRAINMENT. THIS DRY
EASTERLY FLOW ALONG WITH SUBSIDENCE TODAY EXPECTED TO HELP BREAK UP
CLOUDS FROM NORTHEAST TO SOUTHWEST THROUGH THE DAY.
HOWEVER...SATELLITE SHOWS AREA OF STRATUS OVER WI MOVING SLOWLY
SOUTHWARD AND MODELS DO NOT HAVE A GOOD HANDLE ON THIS CLOUD COVER.
LOW LEVEL RH PROGS FROM VARIOUS MODELS ALL SEEM TO SUPPORT DRYING
TODAY FROM THE NORTHEAST BUT RUC13 HAS ALSO SHOWN A TENDENCY FOR
HIGHER RH ACROSS CENTRAL OH TO ADVECT WEST INTO OUR EASTERN AREA
THIS AFTERNOON. ALL THESE CLOUD ISSUES MAKE FOR DIFFICULT FORECAST
TODAY. MOST SURROUNDING OFFICES FAVORING THE CLEARING SCENARIO SO
WILL LEAN TOWARD THE DRYING AND BE OPTIMISTIC WITH SKIES BECOMING
PARTLY CLOUDY AND EVENTUALLY MOSTLY CLEAR TONIGHT. HIGH PRESSURE TO
THEN SLIDE ACROSS THE AREA TONIGHT WITH LIGHT WINDS AND MOSTLY CLEAR
SKIES. THIS SHOULD ALLOW GOOD RADIATIONAL COOLING AND TEMPS TO DROP
BACK TO SINGLE DIGITS EASTERN HALF AND LOWER TEENS WEST WHERE SOME
MID AND HIGH CLOUDS MAY SPILL OVER RIDGE.
&&
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM EST TUE JAN 27 2015
NEXT CLIPPER-TYPE SYSTEM STILL SLATED TO IMPACT THE AREA LATE
WEDNESDAY NIGHT INTO THURSDAY. THIS WAVE WILL ACTUALLY BE AIDED TO
SOME DEGREE BY ANOTHER VORT MAX LEFTOVER FROM OLD BAJA CUTOFF LOW
CURRENTLY BEING REABSORBED INTO THE MEAN WESTERLIES. STILL SOME
INCONSISTENCIES IN THE MODELS REGARDING WHERE EXACTLY THESE TWO
WAVES TRACK AND HOW THEY INTERACT BUT OUR AREA SHOULD SEE A PERIOD
OF DECENT PV ADVECTION/CVA THAT WILL GENERATE AT LEAST SOME FORCED
ASCENT AND LIGHT PRECIP. THE PROBLEM IS THAT UPPER JET SUPPORT IS
MARGINAL AT BEST AND LATEST CONSENSUS TRACK FORECAST KEEPS THE BEST
LOW LEVEL ISENTROPIC ASCENT AND FRONTOGENESIS GENERALLY NORTH OF OUR
AREA. FURTHERMORE...STRONG LOW LEVEL WAA WILL INTRODUCE A MELTING
LAYER ALOFT (AND EVENTUALLY AT THE SURFACE) THAT WILL MAKE
ACCUMULATING SNOW VERY DIFFICULT WITH A HODGEPODGE OF ALL DIFFERENT
PRECIP TYPES OVER SPACE AND TIME. IMPOSSIBLE TO CORRECTLY NAIL DOWN
EXACT TIMING AND LOCATION OF VARIOUS PRECIP TYPES THIS FAR OUT BUT
DID TRY TO PUT A "BEST GUESS" IN THE GRIDS FOR NOW...BASED ON
CONSENSUS OF FORECAST LOW TRACK AND THERMAL PROFILES. PREFERENCE
LIES WITH A GFS/ECMWF COMBO. NAM SURFACE TEMPS APPEAR TOO COLD AND
QPF AMOUNTS TOO LIGHT. GEM THERMAL PROFILES ARE DECENT BUT KEEPS
PRECIP LOCKED UP TOO FAR NORTH. SUPPOSE THIS IS POSSIBLE IF FORECAST
TRACK IS IN LARGE ERROR BUT SOLUTIONS HAVE BEEN FAIRLY STABLE THUS
FAR AND SUSPECT MOST AREAS WILL SEE AT LEAST SOME LIGHT PRECIP WITH
A MODEST PV ANOMALY PASSING DIRECTLY OVERHEAD. THIS IS ESPECIALLY
TRUE GIVEN SUPERB MOISTURE AVAILABILITY WITH 700MB MIXING RATIOS
OVER 4 G/KG AND PW VALUES AROUND 0.75 INCHES. AS FAR AS PRECIP
TYPES...EXPECT COLD SURFACE TEMPS TO SUPPORT FREEZING RAIN AT THE
ONSET...TRANSITIONING TO ALL RAIN FROM SOUTH TO NORTH EARLY THURSDAY
MORNING. LATENT HEAT RELEASE DUE TO FREEZING AND CONTINUAL WAA WITH
S/SW SURFACE WINDS SHOULD LEAD TO A NONDIURNAL TEMPERATURE TREND AND
A FAIRLY QUICK CHANGEOVER TO RAIN WITH MINIMAL ICE ACCUMULATION.
STILL COULD BE SOME SLICK ROADS DURING THE EARLY MORNING COMMUTE
THOUGH...ESPECIALLY NORTH OF US-30. ATYPICAL DIURNAL TEMP TREND
CONTINUES ON THURSDAY WITH HIGHS PROBABLY OCCURRING IN THE LATE
MORNING AND THEN FALLING THROUGH THE AFTERNOON AS COLDER AIR WRAPS
BACK AROUND EXITING LOW. THIS WILL LEAD TO A CHANGE BACK TO SNOW
FROM NORTH TO SOUTH WITH SOME TRANSITORY SLEET MIXING IN AS WELL.
EXPECT SNOW AMOUNTS AROUND AN INCH AT MOST WITH THE HIGHEST AMOUNTS
IN OUR FAR NORTHEAST. ANY ACCUMULATION OF FREEZING RAIN AT THE ONSET
WILL BE LESS THAN A TENTH OF AN INCH. SOME LIGHT LAKE EFFECT/
ENHANCED SNOW POSSIBLE THURSDAY NIGHT BUT BY AND LARGE EVENT WILL BE
WINDING DOWN BY THEN.
NEXT CHANCE OF SNOW LOOKS TO BE ON SUNDAY AS ELONGATED/POSITIVELY
TILTED TROUGH SWINGS THROUGH THE CENTRAL CONUS. MODELS HAVE SHOWN A
HIGH DEGREE OF VARIABILITY DURING THIS TIMEFRAME SO FORECAST
CONFIDENCE IS LOW. DID FOCUS THE POP FORECAST A BIT BUT WILL HOLD
OFF FOR A FEW MORE RUNS BEFORE LATCHING ONTO ANY SPECIFICS. STILL
LOOKS LIKE AT LEAST A GLANCING BLOW OF MUCH COLDER AIR BEHIND THIS
SYSTEM ON MONDAY. NUDGED THE FORECAST TOWARD COLDER RAW GUIDANCE
WITH HIGHS IN THE TEENS AND LOWS FLIRTING WITH 0F.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1235 PM EST TUE JAN 27 2015
VFR WITH LIGHT WINDS EXPECTED THROUGH THE TAF CYCLE. MAY SEE A
SCT CU DECK NEAR 3 KFT MATERIALIZE FOR A BRIEF TIME THIS AFTERNOON
AS MOISTURE STREAMS OFF OF LAKE HURON UNDER A STRENGTHENING
SUBSIDENCE INVERSION. OTHERWISE ANTICIPATE SOME MID-HIGH LEVEL
CLOUDINESS...ESPECIALLY BY TOMORROW AS WAA ENSUES.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...BENTLEY
SHORT TERM...LASHLEY
LONG TERM...AGD
AVIATION...STEINWEDEL
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1145 AM CST TUE JAN 27 2015
.SHORT TERM /TODAY/...
ISSUED AT 355 AM CST TUE JAN 27 2015
MAIN CONCERNS TODAY WILL BE TEMPS AND CLOUD COVER THROUGH THE
MORNING HOURS...AND PERHAPS A PORTION OF THE AFTERNOON EAST. TO
VARYING DEGREES...MODELS ALL HINT AT SOME CLOUDS MOVING SOUTHEAST
ALONG THE EASTERN EDGE OF THE H700 RIDGE CAUGHT IN THE NORTHWEST
FLOW EARLY TODAY. HOWEVER...NONE OF THE MODELS IS DOING VERY WELL.
THE HRRR AND NMM WRF MAY HAVE A SLIGHTLY BETTER HANDLE ON THE
SITUATION. EXAMINING THE UPPER LEVEL H700 RIDGE THROUGH THE DAY
TODAY SHOWS THAT IT IS LIKELY TO CONTINUE BUILDING EAST THROUGH THE
AFTERNOON HOURS...ENDING ANY CYCLONIC PORTION OF CIRCULATION WHICH
IS ASSOCIATED WITH THE LEFTOVER SYSTEM FROM YESTERDAY. AT 00Z TUE
THE H850 ANALYSIS SHOWED A PRONOUNCED WAVE TRACKING THROUGH EASTERN
IOWA BACK NORTH TOWARD MINNEAPOLIS...BUT NORTHWEST OF THERE THE FLOW
BECOMES MORE ANTICYCLONIC OVER THE EASTERN DAKOTAS. ANOTHER UPSTREAM
TROUGH IS ALREADY DEVELOPING WITH AN ATTENDANT WARM FRONT OVER THE
WESTERN DAKOTAS. SOME CLOUDS OVER SASKATCHEWAN AND MANITOBA MAY
TRACK SOUTHEAST TOWARD THE REGION THIS AFTERNOON BUT LIKELY ONLY
AFFECT THE FAR EASTERN COUNTIES WITH MID TO HIGH LEVEL CLOUDS. BASED
ON CLOUDS AND LATER TRAJECTORIES...COOLER HIGHS WILL BE HAD OVER THE
NORTHEAST HALF OF THE FORECAST AREA WHILE THE SOUTHWEST HALF WILL
REMAIN MILD FOR JANUARY...BUT NOT AS WARM AS YESTERDAY. WITH A
RATHER WEAK RIDGE AXIS PASSING OVER THE AREA TODAY WINDS WILL REMAIN
LIGHT. HIGHS WILL RANGE FROM THE UPPER 30S NORTHEAST TO THE UPPER
40S SOUTHWEST.
.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 355 AM CST TUE JAN 27 2015
AM EXPECTING MAX TEMPS FOR WED TO BE VERY SIMILAR TO MONDAY`S HIGHS.
A WARM FRONT WILL CUT ACROSS THE MIDDLE OF THE CWA...LEADING TO A
NOTABLE TEMP GRADIENT...FROM NW TO SE. LOW 40S EXPECTED IN NE CWA
AND UPPER 50S IN SW CWA. NAM MORE AGGRESSIVE WITH LOW LEVEL CLOUD
COVER AND THUS IS A COOL OUTLIER. NAM ALSO STILL THINKS THERE IS
SNOW ACROSS THE CWA SO AM DISCARDING NAM SOLUTION.
A VERY FAST MOVING SHORTWAVE TO IMPACT CWA THURSDAY MORNING. THROUGH
WATER VAPOR IMAGERY...THIS SHORTWAVE CAN BE EASILY PICKED UP COMING
ONTO THE CALIFORNIA COAST AT 06Z TUE. MODELS INITIALIZING WELL WITH
PLACEMENT OF THIS LOW AS IT COMES ONSHORE.
ADDITIONALLY...MODELS CONVERGING ON SOLUTION OF PUTTING THE WAVE
DIRECTLY OVER CENTRAL IOWA AT 06Z THU. THERE IS A SIZABLE DRY AIR
POCKET FROM AROUND 850MB TO 500MB WHICH WILL PREVENT CLOUD
THICKNESS FROM EXCEEDING 5 KFT AND...SUBSEQUENTLY...KEEP THIS
SYSTEM FROM PRODUCING ANYTHING BEYOND LIGHT PRECIP. HAVE BUMPED
UP TEMPS FROM PVS SHIFT. KMCW TO KEST GFS SOUNDINGS SUPPORT MAINLY
DZ/-RA...WITH A VERY NARROW WINDOW OF -IP TO -SN POSSIBLE FROM
AROUND 09Z TO 12Z. PROFILE DURING THIS TIME IS BELOW ZERO UNTIL
NEAR SFC...WHICH IS NOT ENOUGH WARM LAYER DEPTH TO FULLY MELT ALL
SNOW FLAKES. BY 12Z THU...THIS LOW WILL BE OVER NORTHERN ILLINOIS
AND STRONG CAA PLUS SUBSIDENCE WILL BE ADVECTED INTO OUR CWA.
THOUGH SUNSHINE EXPECTED...DAYTIME TEMPS TO ONLY WARM AROUND 3 TO
5 DEGREES FROM OVERNIGHT MINS DUE TO CAA.
THURSDAY`S WINDS ALSO WORTH MENTIONING. MODELS SHOWING 25 KT TO 30
KT WINDS RIGHT OFF THE DECK...APPROACHING 35 KT TO 40 KT TO THE TOP
OF THE MIXED LAYER. SFC PRESSURE GRADIENT OF 3MB/100KM TO SUPPORT
STRONG WINDS AT THE SFC. IN ALL...MAY APPROACH WIND ADVISORY
CRITERIA STARTING EARLY THU AM AND HEADLINE MAY BE WARRANTED IF THIS
SOLUTION HOLDS. A STRONG SFC HIGH WILL MOVE THROUGH THE MIDWEST
FRIDAY...KEEPING FRIDAY QUIET AND HELPING TO DECOUPLE WINDS HEADING
INTO SATURDAY.
FOR THIS WEEKEND...THE 00Z RUNS ARE HOLDING AS THEY ARE SHOWING AN
ALBERTA CLIPPER TYPE SYSTEM LOOKS TO PASS THROUGH THE GREAT LAKES
REGION. THERE WILL BE AN ATTENDANT COLD FRONT TO THIS LOW WHICH IS
BEING PROGGED TO PROPAGATE THROUGH THE CWA SUNDAY MORNING. THE
TIMING HAS CHANGED SOME FROM THE 12Z MON MODEL RUNS TO THE 00Z TUE
RUNS...WITH THE EURO AND GFS DROPPING BACK FROPA UNTIL AROUND 06Z
TO 12Z SUN. MODELS SATURATE THE SKIES FROM TOP DOWN IN ADVANCE OF
THIS SYSTEM...STARTING SATURDAY MORNING. PUSHING TIMING BACK SEEMS
REASONABLE...AS LOW LEVELS NOT SATURATED UNTIL AFTER 00Z SUN. THUS
HAVE PUSHED BACK POPS SLIGHTLY. SOUNDING PROFILE COMPLETELY
SATURATED AND WELL BELOW FREEZING SUNDAY MORNING. HAVE BEGUN TO
NUDGE SUNDAY MORNING POPS UPWARD...WITH FURTHER INCREASES
CERTAINLY POSSIBLE IF THE MODEL SOLNS CONTINUE TO HOLD.
THE PAST FEW MODEL RUNS HAVE CERTAINLY BEEN TRENDING DOWNWARD WITH
TEMPERATURES BEHIND THIS FRONT. ENSEMBLES HAVE 850 MB TEMPS DOWN TO
THE -12C TO -15C RANGE ACROSS THE CWA. SINGLE DIGIT TEMPERATURES
APPEAR VERY POSSIBLE MONDAY AND TUESDAY MORNING.
&&
.AVIATION...27/18Z
ISSUED AT 1145 AM CST TUE JAN 27 2015
LOW LEVEL MOISTURE WILL LIKELY KEEP CLOUDS ACROSS THE FAR EAST AND
NORTH AFFECTING KMCW...KALO AND KOTM THROUGH AT LEAST 21Z. THE
FORECAST BECOMES PROBLEMATIC AFTER 06Z. WINDS SWITCH AROUND TO THE
SE BUT REMAIN LIGHT AND MODELS ARE NOT HANDLING THE LOW LEVEL
MOISTURE VERY WELL. WITH LIGHTER FLOW IT DOES NOT APPEAR THIS
MOISTURE WILL GET MOVED OUT SO I WENT MORE PESSIMISTIC ON THE CLOUD
COVER THROUGH THE PERIOD SINCE ALL MODELS SUGGEST AT LEAST SOME LOW
LEVEL MOISTURE REMAINING THROUGH 28/18Z.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...REV
LONG TERM...KOTENBERG
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS JACKSON KY
201 PM EST TUE JAN 27 2015
.UPDATE...
ISSUED AT 201 PM EST TUE JAN 27 2015
SKIES HAVE BEGUN TO SLOWLY CLEAR OUT FROM NORTH TO SOUTH AS THE AREA
OF CLOUD COVER SLOWLY SLIDES SOUTH ASSOCIATED WITH THE WEAK WAVE THAT
DIVED SOUTH THROUGH EASTERN KENTUCKY THIS MORNING. ADJUSTED CLOUD
COVER FOR THIS AND HAVE TAKEN OUT THE MENTION OF FLURRIES FOR THIS.
DID ADJUST THE MAX TEMPS FOR TODAY AS THE CLEAR SKIES WILL ALLOW FOR
SLIGHTLY WARMER TEMPERATURES.
UPDATE ISSUED AT 1101 AM EST TUE JAN 27 2015
CURRENT OBSERVATIONS ARE SHOWING LOW LEVEL CLOUD COVER AND A FEW
FLURRIES MOVING THROUGH EASTERN KENTUCKY BUT MAINLY OVER THE SOUTHERN
PORTION. MUCH OF THE HEAVIER RETURNS ON RADAR HAVE DISSIPATED AND THE
SNOW SHOWER ACTIVITY HAS DWINDLED SIGNIFICANTLY. STILL CAN RULE OUT A
SLIGHT VISIBILITY REDUCTION INTO THIS AFTERNOON WITH SOME FLURRY
ACTIVITY. HAVE UPDATED THE GRIDS AND REMOVED SNOW SHOWER WORDING BUT
WILL CONTINUE TO INCLUDE SOME ISOLATED TO SCATTERED FLURRIES
THROUGH THE AFTERNOON. HAVE ISSUED A NEW ZFP FOR THESE CHANGES BUT
OVERALL THE FORECAST IS ON TRACK.
UPDATE ISSUED AT 725 AM EST TUE JAN 27 2015
A NEW SNOW BAND DEVELOPED OVER THE BLUEGRASS AREA AND HAS NOW SLIPPED
SOUTHEAST INTO OUR CWA RIDING JUST A TAD NORTHEAST OF THE PREVIOUS
ONE. ONLY BELATEDLY DID THE HRRR CATCH ON TO THIS LATEST BAND...
THOUGH. ACCORDINGLY...HAVE UPDATED THE GRIDS TO REFLECT THE SNOW
MOVEMENT AND ADJUSTED THE LIGHT SNOW AMOUNTS. ALSO FINE TUNED
TEMPERATURES AND DEWPOINTS PER THE LATEST OBS AND TRENDS. THESE HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM EST TUE JAN 27 2015
07Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE OFF TO THE
NORTHEAST WHILE LOCALLY THE PRESSURE GRADIENT IS RATHER RELAXED AND
THIS IS LIMITING THE UPSLOPE COMPONENT OF THIS NIGHT/S SNOW THREAT.
THE MAIN BANDS OF SNOW ARE BEING PRIMARILY DRIVEN BY A SFC TROUGH
AXIS SPLITTING THE STATE AND A STREAM OF MID LEVEL ENERGY RUNNING
NORTH NORTHWEST TO THE SOUTH SOUTHEAST OVER PARTS OF CENTRAL AND
EASTERN KENTUCKY. ON RADAR...THIS BAND LINES UP WELL WITH THIS
ENERGY STREAM AND IS ALSO ABLE TO TAP INTO EXTRA MOISTURE FROM LAKE
MICHIGAN. THE SNOW ASSOCIATED WITH THIS HAS BEEN RELATIVELY LIGHT
WITH MOST SITES REPORTING SNOW SEEING 4SM OR BETTER VIS...THOUGH IT
IS LIKELY THAT UNDER THE HIGHEST RADAR RETURNS VIS IS LESS THAN 2
MILES. FOR THESE LOCATIONS...A COUPLE OF TENTHS OF AN INCH OR SO OF
ACCUMULATION WILL BE POSSIBLE WHILE MOST OTHER PLACES WILL SEE JUST A
THICK DUSTING OR LESS. AN SPS IS IN EFFECT FOR THIS AND IT WILL BE
CONTINUED THROUGH DAWN AND THE MORNING RUSH HOUR FOR GOOD MEASURE.
TEMPERATURES...MEANWHILE ARE IN THE MID TO UPPER 20S ACROSS THE AREA
WITH DEWPOINTS A DEGREE OR SO LOWER AND WINDS LIGHT TO CALM.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST AS A CLOSED LOW DEEPENS OFF THE NEW ENGLAND COAST AND
A STREAM OF ENERGY FLOWS NNW TO SSE OVER KENTUCKY AND INTO THE
BROADER EAST COAST TROUGH TODAY. THIS FLOW WILL BE NUDGED EAST BY A
MODERATELY STRONG RIDGE IN THE SOUTHERN STREAM CROSSING THE SOUTHERN
PLAINS LATER TONIGHT. THIS RIDGE WILL BE PUSHED SOUTH BY A DEVELOPING
TROUGH COMING OUT OF THE CENTRAL ROCKIES AND MOVING INTO THE CENTRAL
PLAINS LATER WEDNESDAY. GIVEN THE GOOD MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE FIRST PART OF THE
FORECAST AND A BLEND THEREAFTER.
SENSIBLE WEATHER WILL FEATURE A BATCH OF EARLY MORNING SNOW SHOWERS
TARGETING MAINLY THE CUMBERLAND VALLEY OF EASTERN KENTUCKY. A FEW
FLURRIES WILL THEN LINGER INTO EARLY AFTERNOON FOR FAR SOUTHEAST
PARTS OF THE CWA BEFORE ALSO COMING TO AN END BY EARLY EVENING AS THE
CLOUDS ATTEMPT TO CLEAR. THIS...ALONG WITH SOME CONTINUED CAA FROM
THE EAST COAST STORM...WILL MAKE FOR A CHILLY NIGHT WITH LOWS IN THE
TEENS FOR WEDNESDAY MORNING. DESPITE HIGH PRESSURE PASSING THROUGH...
A BATCH OF LOW CLOUDS COULD DEVELOP OVERNIGHT AND HUG OUR EASTERN
ZONES INTO DAWN WEDNESDAY...WHICH MAY SPARE THESE AREAS THE COLDEST
TEMPS. THIS LOW LEVEL MOISTURE WILL ALSO NEED TO BE WATCHED FOR A
POTENTIAL OF SPOTTY FREEZING DRIZZLE IF THE STRATUS GETS THICK
ENOUGH. FOR NOW...THOUGH...IT LOOKS LIKE THIS WILL NOT BE THE
CASE...BUT THE POTENTIAL IS THERE. OTHERWISE...THE APPROACH OF
ANOTHER NORTHERN PASSING SFC LOW WILL HELP TO WARM THE AREA UP ON
WEDNESDAY WITH TEMPS REBOUNDING INTO THE MID 30S NORTHEAST TO THE
LOWER 40S SOUTHWEST. HOWEVER...HIGH CLOUDS WILL START TO MOVE IN BY
AFTERNOON FROM THE NORTHWEST LIMITING SUNSHINE ONCE ANY LOW CLOUDS
BREAK UP.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THIS AFTERNOON BEFORE PLUGGING IN THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR...TERRAIN BASED...
ADJUSTMENTS TO HOURLY AND MINIMUM TEMPERATURES TONIGHT. AS FOR
POPS...ENDED UP CLOSE TO A COMBINATION OF THE WETTER MAV AND DRIER
MET TODAY WHILE AGREED WITH THE LOW POPS FROM ALL GUIDANCE TONIGHT
AND WEDNESDAY ACROSS EAST KENTUCKY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 AM EST TUE JAN 27 2015
THE PERIOD BEGINS WITH HIGH PRESSURE CENTERED TO THE NORTH AND EAST
WITH SOME WEAK UPPER LEVEL RIDGING ACROSS THE REGION. EYES TURN
QUICKLY TO APPROACHING SURFACE LOW ACROSS THE MIDWEST THAT IS
FORECAST TO PROGRESS EAST INTO THE GREAT LAKES. A COLD FRONT
EXTENDING SOUTH FROM THE LOW WILL BE THE DRIVER FOR CHANCES OF PRECIP
AS WE MOVE INTO THURSDAY MORNING INTO THURSDAY NIGHT. THEREFORE
WEDNESDAY NIGHT WILL BE MET WITH INCREASING CLOUDS AND CHANCES OF
PRECIP INCREASING AS WE MOVE TOWARD DAYLIGHT ON THURSDAY. THE PRECIP
WILL BRING A CHANCES OF SNOW OR RAIN/SNOW MIX THURSDAY MORNING BEFORE
CHANGING TO ALL RAIN LATE MORNING INTO THURSDAY AS WARMER AIR MAKES
ITS WAY INTO THE REGION. THIS IS ALSO EVIDENT IN THE SOUNDS AS DRYER
AIR IS SEEN IN THE UPPER LEVEL LEADING TO LESS ICE BY THURSDAY
AFTERNOON. OTHERWISE THIS LOW PRESSURE SYSTEM AND ASSOCIATED
SHORTWAVE WILL MOVE EAST THURSDAY NIGHT WITH LOW DEEPENING ACROSS THE
NORTHEAST US. HERE WE SWITCH TO WEST TO NORTHWEST FLOW AND THEREFORE
HAVE KEPT SOME POPS ACROSS EAST AND SOUTHEAST THURSDAY NIGHT INTO
EARLY FRIDAY. THIS WILL LIKELY MIX WITH OR CHANGE TO SNOW AS WE MOVE
THROUGH THE NIGHT. GIVEN LIMITED MOISTURE AT THIS POINT WOULD THINK
LITTLE TO ANY ACCUMULATIONS WOULD BE EXPECTED WITH BEST CHANCES
ACROSS THE HIGHER TERRAIN.
MOVING INTO FRIDAY EXPECT DECREASING CLOUDS AND HIGH PRESSURE TO DROP
SOUTH OUT OF THE UPPER PLAINS. THIS WILL USHER IN GENERALLY BELOW
NORMAL TEMPS FOR FRIDAY. THE QUESTION REMAINS FRIDAY NIGHT AS TO HOW
MUCH THE TEMPS BOTTOM OUT. RIGHT NOW WOULD SEEM LIKE BEST CHANCES FOR
DECOUPLING WOULD BE ACROSS THE NORTH AND FAR EASTERN PORTIONS OF THE
CWA. DID INTRODUCE SOME TEENS TO BETTER MATCH NEIGHBORING OFFICES.
AFTER THIS THE HIGH PRESSURE MOVES EAST WITH RETURN FLOW SATURDAY
WITH TEMPERATURES GENERALLY ABLE TO REBOUND INTO THE UPPER 30S TO
LOWER 40S.
THEN FOCUS SHIFTS TO NEXT SYSTEM DEVELOPING ACROSS THE SOUTHWEST US
AND PLAINS STATES. THIS LOW PRESSURE WILL EVENTUALLY GET PICK UP BY
NORTHERN STREAM SHORTWAVE AND PROGRESS EAST INTO THE MISSISSIPPI
RIVER VALLEY LATE SATURDAY NIGHT. WE DO INTRODUCE SLIGHT TO CHANCE
POPS SATURDAY NIGHT WITH SOME OF THIS MIXING WITH SNOW AND RAIN
BEFORE CHANGING TO ALL RAIN SUNDAY AS LOW PRESSURE DEEPENS ALONG AND
NEAR THE OHIO RIVER VALLEY THROUGH THE DAY SUNDAY. THIS RAIN WILL
ONCE AGAIN TRANSITION TO MIX AND SNOW SUNDAY EVENING AND SUNDAY
NIGHT FROM NORTH TO SOUTH AS COLDER AIR FILTERS INTO THE REGION
BEHIND THIS LOW. GIVEN THE MORE NORTHERN TRACK OF THIS SURFACE LOW
AND BEST QPF AHEAD OF COLDER AIR WOULD THINK THAT ACCUMULATIONS WOULD
BE LIGHT IN TERMS OF ANY SNOW WE ARE ABLE TO GET. KEEP IN MIND THIS
IS STILL IN THE FARTHER REACHES OF THE LONG TERM FORECAST AND WILL
HAVE TO BE FINE TUNED AS WE GET CLOSER TO THE EVENT. AFTER THIS
SYSTEM MOVES EAST WITH SOME NW FLOW SNOW SHOWERS CONTINUING ACROSS
THE EAST AND SOUTHEAST. OTHERWISE COLDER AIR CONTINUES TO FILTER INTO
THE REGION WITH TEMPERATURES STRUGGLING TO MAKE IT ABOVE FREEZING
MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1255 PM EST TUE JAN 27 2015
SKIES ARE BEGINNING TO CLEAR FROM NORTH TO SOUTH ACROSS THE CWA...
WITH CLEAR SKIES BEING REPORTED AT THE SYM/SJS TAF SITES. IN THE
SOUTHERN AND SOUTHWEST PORTIONS OF OUR CWA...EXPECT CIELINGS TO
GRADUALLY LIFT AND CONDITIONS TO IMPROVE FROM MVFR TO VFR THROUGHOUT
THE AFTERNOON/EVENING HOURS. BY 23Z... ALL TAF SITES SHOULD SEE VFR
CONDITIONS. WEATHER WILL REMAIN DRY THROUGH TOMORROW AFTERNOON. WINDS
WILL GENERALLY BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHALLENBERGER
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...JVM
AREA FORECAST DISCUSSION
NWS JACKSON KY
1255 PM EST TUE JAN 27 2015
.UPDATE...
ISSUED AT 1101 AM EST TUE JAN 27 2015
CURRENT OBSERVATIONS ARE SHOWING LOW LEVEL CLOUD COVER AND A FEW
FLURRIES MOVING THROUGH EASTERN KENTUCKY BUT MAINLY OVER THE SOUTHERN
PORTION. MUCH OF THE HEAVIER RETURNS ON RADAR HAVE DISSIPATED AND THE
SNOW SHOWER ACTIVITY HAS DWINDLED SIGNIFICANTLY. STILL CAN RULE OUT A
SLIGHT VISIBILITY REDUCTION INTO THIS AFTERNOON WITH SOME FLURRY
ACTIVITY. HAVE UPDATED THE GRIDS AND REMOVED SNOW SHOWER WORDING BUT
WILL CONTINUE TO INCLUDE SOME ISOLATED TO SCATTERED FLURRIES
THROUGH THE AFTERNOON. HAVE ISSUED A NEW ZFP FOR THESE CHANGES BUT
OVERALL THE FORECAST IS ON TRACK.
UPDATE ISSUED AT 725 AM EST TUE JAN 27 2015
A NEW SNOW BAND DEVELOPED OVER THE BLUEGRASS AREA AND HAS NOW SLIPPED
SOUTHEAST INTO OUR CWA RIDING JUST A TAD NORTHEAST OF THE PREVIOUS
ONE. ONLY BELATEDLY DID THE HRRR CATCH ON TO THIS LATEST BAND...
THOUGH. ACCORDINGLY...HAVE UPDATED THE GRIDS TO REFLECT THE SNOW
MOVEMENT AND ADJUSTED THE LIGHT SNOW AMOUNTS. ALSO FINE TUNED
TEMPERATURES AND DEWPOINTS PER THE LATEST OBS AND TRENDS. THESE HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM EST TUE JAN 27 2015
07Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE OFF TO THE
NORTHEAST WHILE LOCALLY THE PRESSURE GRADIENT IS RATHER RELAXED AND
THIS IS LIMITING THE UPSLOPE COMPONENT OF THIS NIGHT/S SNOW THREAT.
THE MAIN BANDS OF SNOW ARE BEING PRIMARILY DRIVEN BY A SFC TROUGH
AXIS SPLITTING THE STATE AND A STREAM OF MID LEVEL ENERGY RUNNING
NORTH NORTHWEST TO THE SOUTH SOUTHEAST OVER PARTS OF CENTRAL AND
EASTERN KENTUCKY. ON RADAR...THIS BAND LINES UP WELL WITH THIS
ENERGY STREAM AND IS ALSO ABLE TO TAP INTO EXTRA MOISTURE FROM LAKE
MICHIGAN. THE SNOW ASSOCIATED WITH THIS HAS BEEN RELATIVELY LIGHT
WITH MOST SITES REPORTING SNOW SEEING 4SM OR BETTER VIS...THOUGH IT
IS LIKELY THAT UNDER THE HIGHEST RADAR RETURNS VIS IS LESS THAN 2
MILES. FOR THESE LOCATIONS...A COUPLE OF TENTHS OF AN INCH OR SO OF
ACCUMULATION WILL BE POSSIBLE WHILE MOST OTHER PLACES WILL SEE JUST A
THICK DUSTING OR LESS. AN SPS IS IN EFFECT FOR THIS AND IT WILL BE
CONTINUED THROUGH DAWN AND THE MORNING RUSH HOUR FOR GOOD MEASURE.
TEMPERATURES...MEANWHILE ARE IN THE MID TO UPPER 20S ACROSS THE AREA
WITH DEWPOINTS A DEGREE OR SO LOWER AND WINDS LIGHT TO CALM.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION
OF THE FORECAST AS A CLOSED LOW DEEPENS OFF THE NEW ENGLAND COAST AND
A STREAM OF ENERGY FLOWS NNW TO SSE OVER KENTUCKY AND INTO THE
BROADER EAST COAST TROUGH TODAY. THIS FLOW WILL BE NUDGED EAST BY A
MODERATELY STRONG RIDGE IN THE SOUTHERN STREAM CROSSING THE SOUTHERN
PLAINS LATER TONIGHT. THIS RIDGE WILL BE PUSHED SOUTH BY A DEVELOPING
TROUGH COMING OUT OF THE CENTRAL ROCKIES AND MOVING INTO THE CENTRAL
PLAINS LATER WEDNESDAY. GIVEN THE GOOD MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION HRRR AND NAM12 THROUGH THE FIRST PART OF THE
FORECAST AND A BLEND THEREAFTER.
SENSIBLE WEATHER WILL FEATURE A BATCH OF EARLY MORNING SNOW SHOWERS
TARGETING MAINLY THE CUMBERLAND VALLEY OF EASTERN KENTUCKY. A FEW
FLURRIES WILL THEN LINGER INTO EARLY AFTERNOON FOR FAR SOUTHEAST
PARTS OF THE CWA BEFORE ALSO COMING TO AN END BY EARLY EVENING AS THE
CLOUDS ATTEMPT TO CLEAR. THIS...ALONG WITH SOME CONTINUED CAA FROM
THE EAST COAST STORM...WILL MAKE FOR A CHILLY NIGHT WITH LOWS IN THE
TEENS FOR WEDNESDAY MORNING. DESPITE HIGH PRESSURE PASSING THROUGH...
A BATCH OF LOW CLOUDS COULD DEVELOP OVERNIGHT AND HUG OUR EASTERN
ZONES INTO DAWN WEDNESDAY...WHICH MAY SPARE THESE AREAS THE COLDEST
TEMPS. THIS LOW LEVEL MOISTURE WILL ALSO NEED TO BE WATCHED FOR A
POTENTIAL OF SPOTTY FREEZING DRIZZLE IF THE STRATUS GETS THICK
ENOUGH. FOR NOW...THOUGH...IT LOOKS LIKE THIS WILL NOT BE THE
CASE...BUT THE POTENTIAL IS THERE. OTHERWISE...THE APPROACH OF
ANOTHER NORTHERN PASSING SFC LOW WILL HELP TO WARM THE AREA UP ON
WEDNESDAY WITH TEMPS REBOUNDING INTO THE MID 30S NORTHEAST TO THE
LOWER 40S SOUTHWEST. HOWEVER...HIGH CLOUDS WILL START TO MOVE IN BY
AFTERNOON FROM THE NORTHWEST LIMITING SUNSHINE ONCE ANY LOW CLOUDS
BREAK UP.
USED THE BCCONSSHORT AS A STARTING POINT FOR TEMPERATURES...
DEWPOINTS...AND WINDS THROUGH THIS AFTERNOON BEFORE PLUGGING IN THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR...TERRAIN BASED...
ADJUSTMENTS TO HOURLY AND MINIMUM TEMPERATURES TONIGHT. AS FOR
POPS...ENDED UP CLOSE TO A COMBINATION OF THE WETTER MAV AND DRIER
MET TODAY WHILE AGREED WITH THE LOW POPS FROM ALL GUIDANCE TONIGHT
AND WEDNESDAY ACROSS EAST KENTUCKY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 419 AM EST TUE JAN 27 2015
THE PERIOD BEGINS WITH HIGH PRESSURE CENTERED TO THE NORTH AND EAST
WITH SOME WEAK UPPER LEVEL RIDGING ACROSS THE REGION. EYES TURN
QUICKLY TO APPROACHING SURFACE LOW ACROSS THE MIDWEST THAT IS
FORECAST TO PROGRESS EAST INTO THE GREAT LAKES. A COLD FRONT
EXTENDING SOUTH FROM THE LOW WILL BE THE DRIVER FOR CHANCES OF PRECIP
AS WE MOVE INTO THURSDAY MORNING INTO THURSDAY NIGHT. THEREFORE
WEDNESDAY NIGHT WILL BE MET WITH INCREASING CLOUDS AND CHANCES OF
PRECIP INCREASING AS WE MOVE TOWARD DAYLIGHT ON THURSDAY. THE PRECIP
WILL BRING A CHANCES OF SNOW OR RAIN/SNOW MIX THURSDAY MORNING BEFORE
CHANGING TO ALL RAIN LATE MORNING INTO THURSDAY AS WARMER AIR MAKES
ITS WAY INTO THE REGION. THIS IS ALSO EVIDENT IN THE SOUNDS AS DRYER
AIR IS SEEN IN THE UPPER LEVEL LEADING TO LESS ICE BY THURSDAY
AFTERNOON. OTHERWISE THIS LOW PRESSURE SYSTEM AND ASSOCIATED
SHORTWAVE WILL MOVE EAST THURSDAY NIGHT WITH LOW DEEPENING ACROSS THE
NORTHEAST US. HERE WE SWITCH TO WEST TO NORTHWEST FLOW AND THEREFORE
HAVE KEPT SOME POPS ACROSS EAST AND SOUTHEAST THURSDAY NIGHT INTO
EARLY FRIDAY. THIS WILL LIKELY MIX WITH OR CHANGE TO SNOW AS WE MOVE
THROUGH THE NIGHT. GIVEN LIMITED MOISTURE AT THIS POINT WOULD THINK
LITTLE TO ANY ACCUMULATIONS WOULD BE EXPECTED WITH BEST CHANCES
ACROSS THE HIGHER TERRAIN.
MOVING INTO FRIDAY EXPECT DECREASING CLOUDS AND HIGH PRESSURE TO DROP
SOUTH OUT OF THE UPPER PLAINS. THIS WILL USHER IN GENERALLY BELOW
NORMAL TEMPS FOR FRIDAY. THE QUESTION REMAINS FRIDAY NIGHT AS TO HOW
MUCH THE TEMPS BOTTOM OUT. RIGHT NOW WOULD SEEM LIKE BEST CHANCES FOR
DECOUPLING WOULD BE ACROSS THE NORTH AND FAR EASTERN PORTIONS OF THE
CWA. DID INTRODUCE SOME TEENS TO BETTER MATCH NEIGHBORING OFFICES.
AFTER THIS THE HIGH PRESSURE MOVES EAST WITH RETURN FLOW SATURDAY
WITH TEMPERATURES GENERALLY ABLE TO REBOUND INTO THE UPPER 30S TO
LOWER 40S.
THEN FOCUS SHIFTS TO NEXT SYSTEM DEVELOPING ACROSS THE SOUTHWEST US
AND PLAINS STATES. THIS LOW PRESSURE WILL EVENTUALLY GET PICK UP BY
NORTHERN STREAM SHORTWAVE AND PROGRESS EAST INTO THE MISSISSIPPI
RIVER VALLEY LATE SATURDAY NIGHT. WE DO INTRODUCE SLIGHT TO CHANCE
POPS SATURDAY NIGHT WITH SOME OF THIS MIXING WITH SNOW AND RAIN
BEFORE CHANGING TO ALL RAIN SUNDAY AS LOW PRESSURE DEEPENS ALONG AND
NEAR THE OHIO RIVER VALLEY THROUGH THE DAY SUNDAY. THIS RAIN WILL
ONCE AGAIN TRANSITION TO MIX AND SNOW SUNDAY EVENING AND SUNDAY
NIGHT FROM NORTH TO SOUTH AS COLDER AIR FILTERS INTO THE REGION
BEHIND THIS LOW. GIVEN THE MORE NORTHERN TRACK OF THIS SURFACE LOW
AND BEST QPF AHEAD OF COLDER AIR WOULD THINK THAT ACCUMULATIONS WOULD
BE LIGHT IN TERMS OF ANY SNOW WE ARE ABLE TO GET. KEEP IN MIND THIS
IS STILL IN THE FARTHER REACHES OF THE LONG TERM FORECAST AND WILL
HAVE TO BE FINE TUNED AS WE GET CLOSER TO THE EVENT. AFTER THIS
SYSTEM MOVES EAST WITH SOME NW FLOW SNOW SHOWERS CONTINUING ACROSS
THE EAST AND SOUTHEAST. OTHERWISE COLDER AIR CONTINUES TO FILTER INTO
THE REGION WITH TEMPERATURES STRUGGLING TO MAKE IT ABOVE FREEZING
MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1255 PM EST TUE JAN 27 2015
SKIES ARE BEGINNING TO CLEAR FROM NORTH TO SOUTH ACROSS THE CWA...
WITH CLEAR SKIES BEING REPORTED AT THE SYM/SJS TAF SITES. IN THE
SOUTHERN AND SOUTHWEST PORTIONS OF OUR CWA...EXPECT CIELINGS TO
GRADUALLY LIFT AND CONDITIONS TO IMPROVE FROM MVFR TO VFR THROUGHOUT
THE AFTERNOON/EVENING HOURS. BY 23Z... ALL TAF SITES SHOULD SEE VFR
CONDITIONS. WEATHER WILL REMAIN DRY THROUGH TOMORROW AFTERNOON. WINDS
WILL GENERALLY BE LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHALLENBERGER
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...JVM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
200 PM EST TUE JAN 27 2015
.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY AS IT TRACKS
NORTH NORTHEAST OFF THE NEW ENGLAND COAST THROUGH TONIGHT.
MEANWHILE...HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC
THROUGH MIDWEEK. A COLD FRONT WILL CROSS THE AREA THURSDAY
NIGHT...FOLLOWED BY HIGH PRESSURE THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WINTER WX ADVSRYS HAVE BEEN SCALED BACK THIS MORNG AS THE SNOW HAS
ENDED IN SOME AREAS. THIS TREND WILL CONTINUE THRU THE LATE MORNG
HRS. ALSO ADDED AN SPS FOR AREAS S OF THE ADVSRY AREA WHERE UP TO
ONE INCH OF ACCUMULATION IS PSBL...BUT MAINLY ON GRASSY SFCS.
PREVIOUS DISCUSSION...
QUICK UPDATE TO CLEAR MARYLAND EASTERN SHORE COUNTIES FROM WITNER
WX ADVISORY BASED ON RADAR TRENDS. GIVEN LATEST REPORTS AND
TRAFFIC CAMS IN METRO RIC/ORF AREAS, WILL CONTINUE THEM ELSWEHERE.
EARLY MORNING RADAR MOSAIC SHOWING NARROW BAND OF PCPN DROPPING
SOUTH FROM CENTRAL PA SOUTH INTO EASTERN/CENTRAL VA. VSBY AVGG
2-4SM IN SN, AND WE`VE RECEIVED QUITE A FEW REPORTS ~1 AND A FEW
IN THE 1 1/2 TO 2" ALONG THE NORTHERN NECK INTO THE PENINSULA.
TRAFFIC CAMS SHOWING AT LEAST A COATING INTO THE TIDEWATER AREA
(CONFIRMED BY LOCAL COOPERATIVE OBSERVER). WE WILL BE MAINTAINING
WINTER HEADLINES FOR A LITTLE LONGER, WITH THIS BAND OF SNSH WELL
HANDLED BY THE HRRR EARLY THIS MORNING. NOT EXPECTING ANY LOCALES
IN NORFOLK OR RICHMOND METRO AREAS WILL RECEIVE ANY MORE THAN AN
INCH...BUT WITH THE HEADLINE ALREADY IN PLACE AND THE POTENTIAL
FOR SNOW TO CAUSE SOME IMPACTS DURING THE MORNING COMMUTE...DON`T
FEEL DROPPING THE HEADLINES IS PRUDENT ATTM. WL REVISIT HEADLINES
AT 7AM UPDATE. DO EXPECT DAY CREW WILL BE ABLE TO CLEAR HEADLINES
SHORTLY AFTER 14Z IF NOT SOONER.
HAVE BUMPED POPS UP IN TO CATEGORICAL RANGE FOR COASTAL NE NC, AND
GRADUALLY TAPERED THEM OFF ALONG THE EASTERN SHORE BY MID-LATE
MORNING. DROPPED POPS INTO NO HIGHER THAN 20% BUT HAVE KEPT
FLURRIES IN THE FORECAST FOR FAR WESTERN ZONES, AS ACCUMS NOT
ANTICIPATED.
INTENSIFYING SFC LOW WILL CONTINUE TO LIFT NE INTO NEW ENGLAND
THROUGH TONIGHT. ALL POPS DROP OFF BY EARLY AFTN, WITH STRONG CAA
BRINGING BREEZY/WINDY CONDITIONS (25-30MPH GUSTS ALONG THE
COAST/ERN SHORE), AND HOLDING HIGHS IN THE MID TO UPPER 30S (~40
IN THE PIEDMONT) UNDER A CLOUDY TO MOSTLY CLOUDY SKY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED COASTAL LOW PULLS TOWARDS ATLANTIC
CANADA AS COLD SFC HIGH PRESSURE BUILDS IN FROM THE W. CLEARING
SKY AND GRADUALLY DIMINISHING NW WINDS WILL ALLOW EARLY MORNING
LOW TEMPS TO FALL INTO THE THE 20S FOR MOST, W/ WIND CHILLS IN THE
TEENS IN MOST LOCATIONS.
HIGH PRESSURE BUILDS OVER THE LOCAL AREA ON WEDNESDAY.
TEMPERATURES REMAIN COOL WITH SHALLOW MIXING AND A NNE WIND. HIGHS
ONLY RANGING FROM THE MID 30S OVER THE LWR ERN SHORE TO THE UPR
30S TO LWR 40S ELSEWHERE. DRY AGAIN FOR WED NIGHT WITH LOWS IN THE
20S TO NEAR 30 ALONG THE COAST.
RAIN CHCS INCREASE ACROSS THE AREA LATER THU/THU NGT AS NORTHERN
STREAM SHORTWAVE TROUGH TRACKS FROM THE UPPER MIDWEST ACROSS TO
THE GREAT LAKES, WITH THE ASSOCIATED SFC LOW PUSHING ACROSS THE
NORTHERN MID-ATLANTIC INTO NEW ENGLAND BY LATE THU NGT. DAY BEGINS
PARTLY CLOUDY WITH GRADUALLY INCREASING CLOUDS. BEST FORCING
REMAINS OFF TO THE NORTH, SO HAVE CAPPED POP AT NO HIGHER THAN 30%
FOR NOW. RAIN CHANCES DIMINISH THU NGT AS SFC COLD FRONT PUSHES
ACROSS THE AREA. FOR HIGHS, SW FLOW AHEAD OF THE FRONT WILL ALLOW
FOR A MODEST WARMUP WITH MAXIMA IN THE U30S ERN SHORE/NRN
NECK...LOWER TO MID 40S INLAND AND U40S FAR SOUTHERN ZONES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. HIGH PRESSURE BUILDS IN FROM THE
WEST FRIDAY AND SATURDAY. ANOTHER COLD FRONT APPROACHES FROM THE
NW AND THEN MOVES ACROSS THE REGION LATE SUNDAY. EURO HAS A QUICK
MOVING FRONTAL WAVE MOVE ACROSS THE CAROLINAS LATE SUNDAY AND OUT
TO SEA MONDAY. THERE WILL BE A CHC FOR RAIN OR SNOW WITH THIS
SYSTEM BUT CONFIDENCE FOR SIGNIFICANT WINTER WEATHER IS LOW AT
THIS POINT.
HIGH TEMPERATURES ARE FORECAST IN THE UPR 30S AND 40S THURSDAY
LOWERING TO MOSTLY 30S TO AROUND 40 SATURDAY THROUGH MONDAY. LOWS
ARE EXPECTED TO RANGE THROUGH THE 30S FRIDAY MORNING AND MOSTLY 20S
SATURDAY THROUGH MONDAY MORNINGS.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
THE EFFECTS OF THE STORM IN TERMS OF SNOW AND IFR CONDS HAVE JUST
ABOUT ENDED. THERE ARE STILL LIGHT SNOW SHOWERS OR FLURRIES SW RIC
AS OF 18Z. CLOUDS (MOSTLY MVFR CIGS) ARE THINNING OUT AND SHOULD
CLEAR LATE AFTN/EVENING. WINDS WILL CONTINUE GUSTY FROM THE N/NW
THROUGH THE TAF PERIOD AND FOLLOWED CLOSE TO LAVMOS FOR THOSE WINDS.
OUTLOOK...VFR/DRY WEATHER IS EXPECTED TUE NIGHT THROUGH THU AFTN. A
WEAK SYSTEM MAY DROP CIGS AND VSBYS IN LIGHT RAIN THU NIGHT/EARLY
FRI. A RETURN TO DRY WEATHER IS EXPECTED DURING MOST OF THE WEEKEND.
&&
.MARINE...
UPDATE...DOWNGRADED THE GALE WARNING TO SCA FLAGS FOR NRN COASTAL
WATERS FROM FENWICK ISLAND TO PARRAMORE ISLAND. WIND GUSTS HAVE
STRUGGLED TO REACH 34KT OR GREATER AT SFC BUOYS. SCA FOR NRN WATERS
WILL NOW BE IN EFFECT THROUGH MIDNIGHT WEDNESDAY NIGHT...AFTER WHICH
WINDS AND PRIMARILY SEAS WILL DROP BELOW SCA THRESHOLDS.
PREVIOUS DISCUSSION...STRONG COASTAL LOW IS LOCATED ABOUT 225 MILES
EAST OF ATLANTIC CITY NJ AS OF 4 AM. THE SFC PRESSURE GRADIENT
REMAINS VERY TIGHT...ESPECIALLY ALONG THE ATLANTIC COAST. THE ADDED
CAA AND DIURNAL EFFECTS ARE CAUSING N-NW WINDS TO EXPERIENCE A BRIEF
SURGE IN SPEEDS. SEAS HAVE QUICKLY RISEN TO 8-12FT IN SRN COASTAL
WATERS AS WELL. THE SURGE IN WINDS/SEAS IS EXPECTED TO BE BRIEF...
LASTING THROUGH SUNRISE...AFTER WHICH WINDS WILL DIMINISH SLIGHTLY
AND SEAS WILL SLOWLY SUBSIDE THROUGH THIS AFTN TO 5-7FT SRN
WATERS/6-10FT NRN WATERS...AS THE LOW TRACKS NE AND AWAY FROM THE
MID ATLANTIC COAST. FOR TONIGHT...THE STRONG LOW TRACKS TWD THE
CANADIAN MARITIMES AS HIGH PRESSURE BUILDS OVER THE OHIO VALLEY...
KEEPING A TIGHT PRESSURE GRADIENT OVER THE WATERS. PRESSURE RISES
AROUND 3MB THIS EVENING (OCCURRING BTWN 21Z TODAY AND 06Z TONIGHT)...
INDICATE THAT ANOTHER NWLY SURGE WITH GUSTS AROUND 30KT IS POSSIBLE
THIS EVENING FOR THE BAY/OCEAN AS CAA AND WRAPAROUND SHORTWAVE
ENERGY TRAVERSE THE WATERS.
HIGH PRESSURE SLOWLY BUILDS INTO THE MID ATLANTIC REGION ON WED.
CONTINUED CAA WILL KEEP NW WINDS ELEVATED WITHIN SCA THRESHOLDS
OVER ALL WATERS THROUGH THE DAY. HOWEVER...SEAS WILL SHOW A MARKED
DECREASE TO 4-5FT BY WED AFTN. ONLY CHANGE MADE TO SCA FLAGS WAS
TO EXTEND CHES BAY AND SRN COASTAL WATERS THROUGH 10 PM WED
EVENING BEFORE WINDS/SEAS FALL BELOW SCA THRESHOLDS. SEAS CONTINUE
TO SUBSIDE THRU WED EVENING AS HIGH PRESSURE SLIDES OVER THE
WATERS. A CLIPPER SYSTEM APPROACHING THE REGION ON THU WILL SHUNT
THE HIGH OVER THE SE COAST. THE COLD FRONT ASSOCIATED WITH THE
CLIPPER IS THEN EXPECTED TO CROSS THE WATERS THU NIGHT...FOLLOWED
BY POTENTIALLY SOLID SCA CONDITIONS FRI/FRI NIGHT.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY FOR OCEAN CITY HAS BEEN CANCELLED...FELL
SHORT OF MINOR FLOODING THRESHOLDS AS WINDS SHIFTED FASTER THAN
EXPECTED FROM ONSHORE E/NE MON AFTN TO OFFSHORE N/NW. DEPARTURES
HAVE BEEN BETWEEN 1.5 AND 2 FT ABOVE ASTRONOMICAL TIDE. MDL
GUIDANCE SHOWS THE UPCOMING TIDE THIS AFTN REACHING ABOVE 4 FT
MLLW...BUT THIS APPEARS WELL OVERDONE GIVEN THE N/NW WIND
DIRECTION AND CURRENT OBS AND TRENDS. NAM- BASED CBOFS GUIDANCE IS
RUNNING ABOUT 2 FT HIGHER THAN REALITY...BUT IN TERMS OF TREND
SHOWS THE TIDE THIS AFTN TO BE SLIGHTLY LOWER THAN THE HIGH TIDE
EARLIER THIS MORNING THAT ONLY PEAKED AT 3.7 FT MLLW. HAVE ISSUED
A COASTAL FLOOD STATEMENT RATHER THAN AN ADVISORY AT THIS POINT
GIVEN THE UNFAVORABLE OFFSHORE WIND FLOW.
ACRS THE LOWER BAY DEPARTURES ARE ALSO RUNNING AS HIGH AS 1.5 TO 2
FEET...BUT THIS STILL LEADS TO TIDES FALLING AT LEAST 0.5 FT SHY
OF MINOR FLOODING THIS AFTN. DEPARTURES WILL FALL TONIGHT INTO WED
WITH NO FLOODING CONCERNS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ633-
635>638.
SMALL CRAFT ADVISORY UNTIL 10 PM EST WEDNESDAY FOR ANZ630>632-
634-654-656-658.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST WEDNESDAY NIGHT FOR
ANZ650-652.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAS/MAM
SHORT TERM...MAS/MAM
LONG TERM...LSA
AVIATION...LSA
MARINE...BMD
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EST TUE JAN 27 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 426 PM EST TUE JAN 27 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN AMPLIFIED PATTERN OVER
THE CONUS...FEATURING A STRONG RIDGE OVER THE ROCKIES AND A DEEP
TROF ALONG THE E COAST. RESULTING NW FLOW INTO THE GREAT LAKES IS
QUIETER TODAY THAN YESTERDAY AS SUBTLE SHORTWAVE RIDGING IS JUST
UPSTREAM OVER NRN ONTARIO. SO...THERE IS NO PCPN OF NOTE TODAY.
THERE HAVE BEEN SOME -SHSN/FLURRIES OFF NRN LAKE MICHIGAN INTO
MENOMINEE COUNTY...AND RECENTLY FLURRIES HAVE APPEARED ON KMQT RADAR
IMAGERY IN CNTRL UPPER MI. AT THE SFC...HIGH PRES IS CENTERED OVER
SRN QUEBEC WITH RIDGE EXTENDING BACK THRU THE UPPER LAKES. DRY AIR
ASSOCIATED WITH THE HIGH HAS RESULTED IN A SUNNY DAY OVER ERN UPPER
MI...ROUGHLY E OF A MUNISING-ESCANABA LINE. LOW CLOUDS HAVE BEEN
PERSISTENT OVER THE REST OF THE AREA...THOUGH PORTIONS OF NW UPPER
MI DID HAVE MOSTLY SUNNY SKIES EARLIER TODAY.
QUIET WEATHER WILL CONTINUE TONIGHT WITH SHORTWAVE RIDGING PASSING
ACROSS THE AREA. MAIN ISSUE WILL BE CLOUD TRENDS AND THE BIG IMPACT
THE CLOUDS WILL HAVE ON TEMPS. WITH CLEAR SKIES AND LIGHT/CALM WIND
TO START THE EVENING...THE ERN FCST AREA WILL BE COLDEST TONIGHT.
LOWERED MINS TO AROUND 0F IN THAT AREA...BUT IT COULD BE 5 OR MORE
DEGREES COLDER IF SKIES REMAIN CLEAR THRU THE WHOLE EVENING.
OVERNIGHT...THERE WILL BE AN INCREASE IN CLOUDS DUE TO HIGH CLOUDS
STREAKING SE WELL AHEAD OF THE NEXT SHORTWAVE MOVING ACROSS THE SRN
CANADIAN ROCKIES AND POSSIBLY FROM LOW CLOUDS ADVECTING NE IN
DEVELOPING SW FLOW. THIS WILL PUT THE BRAKES ON COOLING AND PROBABLY
LEAD TO TEMPS RISING SOME OVERNIGHT. ACROSS THE REST OF THE FCST
AREA...THE EXPANSE OF LOW CLOUDS EXTENDING W...SW AND S OVER MUCH OF
MN AND WI SUGGESTS CLOUDS WILL DOMINATE FOR MUCH OF THE NIGHT UNDER
LOW-LEVEL S TO SW WINDS. EVEN IF LOW CLOUDS CLEAR OUT IN SOME
AREAS...HIGH AND MID CLOUDS WILL BE OVERSPREADING THE AREA. LOWS
SHOULD GENERALLY BE IN THE 15-20F RANGE.
ON WED....ONE SHORTWAVE WILL MOVE FROM THE SRN CANADIAN ROCKIES INTO
THE DAKOTAS/MANITOBA WHILE A SECOND MOVES FROM WY/CO TO THE CNTRL
PLAINS. AHEAD OF THE NRN WAVE...WAA/ISENTROPIC ASCENT WILL
STRENGTHEN AND SHIFT ESE THRU THE DAY UNDERNEATH RIGHT ENTRANCE OF
UPPER JET. WITH THE FOCUS OF MOIST ISENTROPIC ASCENT JUST TO THE N
AND WITH DRIER AIR HOLDING ON AT LOW LEVELS...THE MAIN STREAK OF
SNOW WILL REMAIN N OF HERE WED AFTN. MODEL AGREEMENT IS IN EXCELLENT
AGREEMENT ON THIS POINT. HOWEVER...THERE IS SOME UNCERTAINTY IN
WHETHER THE SRN EDGE OF THE SNOW MAY CLIP THE AREA. BASED ON
STRENGTH OF ISENTROPIC ASCENT AND TEMP/MOISTURE PROFILES ON FCST
SOUNDINGS...THE KEWEENAW AND FAR ERN FCST AREA MAY GET CLIPPED BY A
LITTLE -SN. INCLUDED ONLY SCHC/LOW CHC POPS TO REFLECT THIS
POTENTIAL. OTHERWISE...EXPECT A WARMER DAY WITH HIGHS IN THE UPPER
20S/LWR 30S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 313 PM EST TUE JAN 27 2015
AN UPPER RIDGE OVER THE WESTERN COAST OF NORTH AMERICA AND AN UPPER
LOW OVER HUDSON BAY WILL KEEP NORTHWEST FLOW OVER THE UPPER GREAT
LAKES REGION FOR MUCH OF THE LONG TERM PERIOD. THIS WILL LEAD TO
SEVERAL SHORTWAVES DROPPING SOUTHEAST ACROSS THE REGION...WHILE THE
UPPER LOW OVER HUDSON BAY GRADUALLY SINKS SOUTH TOWARDS THE AREA.
THUS...EXPECT GRADUALLY COOLING TEMPERATURES THROUGH EARLY NEXT
WEEK.
THREE PIECES OF ENERGY WITHIN THE LARGER SHORTWAVE TROUGH MOVING
THROUGH THE UPPER GREAT LAKES REGION WEDNESDAY NIGHT AND THURSDAY
WILL BE DRIVING THE WEATHER FOR THE START OF THE LONG TERM PERIOD.
THE SOUTHERN TWO WAVES WILL BE SUPPORTING THE SURFACE LOW MOVING
THROUGH SOUTHERN WISCONSIN AND THE INVERTED TROUGH CROSSING THE
UPPER GREAT LAKES REGION. AT THE START OF THE LONG TERM
PERIOD...EXPECT THE HEAVIEST PRECIPITATION TO BE ONGOING OVER
NORTHERN ONTARIO AND FAR NORTHERN LAKE SUPERIOR...WHILE THERE WILL
BE SOME SNOW OVER EASTERN UPPER MICHIGAN TIED TO THE NOSE OF THE
850-700MB WARM AIR ADVECTION INTERACTING WITH THE DEEPER MOISTURE.
THINKING MUCH OF THE REST OF THE AREA WILL BE SEEING LIMITED
PRECIPITATION CHANCES WITH THE POCKET OF DRY AIR BETWEEN 925-750MB.
THEN AS THE 850-700MB TROUGH SWEEPS SOUTHEAST THROUGH THE AREA
THROUGH THE NIGHT...EXPECT SNOW TO QUICKLY SPREAD INTO THE AREA
THROUGH THE EVENING/OVERNIGHT HOURS. WITH THAT INITIAL PRECIPITATION
STAYING TO THE NORTH OF THE LAND AREA INITIALLY...HAVE TRENDED
QPF/SNOW AMOUNTS DOWN SLIGHTLY OVER THE WEST/CENTRAL (1-2IN).
NORTHEAST OF A LINE FROM HOUGHTON TO MANISTIQUE...HAVE AMOUNTS IN
THE 2-3.5 INCH RANGE AND WILL CONTINUE TO MENTION IN THE HWO FOR
THOSE AREAS. AS THE DEEPER MOISTURE DEPARTS THURSDAY
MORNING...WILL SEE THE SNOW DIMINISH...BUT THINK THERE WILL BE
ENOUGH TERRAIN INFLUENCE TO HELP KEEP SNOW SHOWERS IN THE
NORTH-NORTHWESTERLY WIND SNOW BELTS UNTIL THE COLD AIR ARRIVES
THURSDAY AFTERNOON AND INCREASES DELTA-T VALUES TOWARDS THE LOW 20S
BY THURSDAY EVENING. THERE ARE HINTS OF LIMITED ICE CRYSTALS (AND
THUS FREEZING DRIZZLE) OVER THE WEST AS THAT DEEP MOISTURE
DEPARTS...BUT THINK IT IS TOO MARGINAL TO MENTION AT THIS POINT.
WITH THAT COLD AIR ARRIVING FROM NORTHWEST TO SOUTHEAST ON THURSDAY
AFTERNOON/EVENING...SHOULD SEE LAKE EFFECT COVERAGE INCREASING
DURING THAT TIME FRAME. WILL TREND POPS UP TO LIKELY/DEFINITE VALUES
FOR THE FAVORED NORTHWEST WIND SNOW BELTS FOR THURSDAY NIGHT. WHILE
SNOW IS EXPECTED...THERE ARE A COUPLE LIMITING FACTORS FOR HIGHER
SNOWFALL AMOUNTS. FIRST...THE APPROACHING HIGH PRESSURE RIDGE WILL
KEEP THE SUBSIDENCE INVERSION AROUND 5KFT THROUGH THE PERIOD. WHILE
MUCH OF THE CLOUD WILL BE IN OR JUST ABOVE THE DGZ...THINK THE
FRACTURING OF THE FLAKES FROM THE GUSTY WINDS WILL KEEP SNOW RATIOS
LOWER (BUT BE BETTER AT REDUCING VISIBILITIES). THUS...HAVE
SNOWFALL AMOUNTS OF 1-4 INCHES IN THE FAVORED SNOW BELTS DURING THAT
PERIOD. AS THE HIGH MOVES JUST SOUTH OF THE AREA ON FRIDAY...EXPECT
WINDS TO BACK TOWARDS THE WEST AND LOWER THE SUBSIDENCE INVERSION
TOWARDS 4KFT. THEREFORE...WILL GRADUALLY DIMINISH PRECIPITATION
CHANCES THROUGH FRIDAY AS WINDS BACK TO THE SOUTHWEST ON FRIDAY
NIGHT.
THE NEXT CLIPPER WILL SWEEP ACROSS THE AREA SATURDAY AND DRAG A WEAK
SURFACE TROUGH WITH IT. STILL SOME DIFFERENCES IN THE TIMING WITH
THIS FEATURE...SO WILL GO WITH LOW END CHANCE POPS SPREADING ACROSS
THE CWA ON SATURDAY. OVERALL...LOOKS LIKE JUST A QUICK DUSTING OF
SNOW WITH THIS FEATURE. BEHIND THE TROUGH...COLD AIR WILL FILTER
BACK INTO THE UPPER GREAT LAKES REGION AND BRING ANOTHER PERIOD OF
LAKE EFFECT FOR THE NORTH-NORTHWEST WIND SNOWBELTS. ONCE AGAIN...THE
HIGH PRESSURE RIDGE NOSING EAST INTO THE AREA WILL KEEP THE
SUBSIDENCE INVERSION AROUND 5KFT AND KEEP THE LAKE EFFECT AMOUNTS ON
THE LIGHT SIDE. ONE ITEM TO WATCH IS THE POTENTIAL FOR A WEAK
SHORTWAVE SLIDING ACROSS THE AREA ON MONDAY. THERE ARE HINTS THAT
THIS MAY RAISE INVERSION HEIGHTS TOWARDS 7-10KFT...WHICH WOULD
PROVIDE THE POTENTIAL FOR MODERATE LAKE EFFECT. WHEN THAT
OCCURS...WITH ANOTHER SURGE OF COLD AIR (850MB TEMPS FALLING TO THE
MID -20S) THE CLOUD WILL BE WELL ABOVE THE DGZ AND SUPPORT SMALL
FLAKES THAT ARE HIGHLY EFFICIENT AT REDUCING VISIBILITY. WITH THE
HIGH MOVING SOUTHEAST FROM THE NORTHERN PLAINS ON MONDAY MORNING TO
THE OHIO RIVER VALLEY ON TUESDAY...EXPECT GRADUALLY BACKING WINDS
OVER LAKE SUPERIOR AND WILL FOLLOW THAT IDEA FOR AT LEAST LIKELY
POPS FOR THE FAVORED WIND DIRECTIONS THROUGH TUESDAY (WINDS NEAR
WESTERLY BY TUESDAY EVENING). WON/T MENTION IN THE HWO AT THIS
POINT...AS AMOUNTS WILL BE ON THE LOW SIDE...BUT MAY NEED TO ADDRESS
THE END OF THE WEEK LAKE EFFECT AND THE SUN-TUE LAKE EFFECT IN THE
FUTURE DUE TO THE LIKELY LOW VISIBILITIES IN THE STRONGER BANDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1238 PM EST TUE JAN 27 2015
LINGERING LOW CLOUDS WILL BE SLOW TO EXIT OVER MUCH OF THE W HALF OF
UPPER MI THIS AFTN/EVENING UNDER LIGHT WIND FIELDS. AT KIWD/KSAW...
MVFR CIGS ARE LIKELY TO LINGER INTO THE EVENING. SLIGHT
STRENGTHENING OF DOWNSLOPE WIND SHOULD ALLOW MVFR CIGS TO SCATTER
OUT AT KIWD LATE THIS EVENING. IT MAY NOT BE UNTIL OVERNIGHT THAT
MVFR CIGS SCATTER OUT AT KSAW. RECENT VIS SATELLITE IMAGERY SHOWS
GRADUAL EXPANSION OF LOWER CLOUDS TOWARD KCMX. SO...IT APPEARS MVFR
CIGS WILL LIKELY DEVELOP AT KCMX IN THE NEXT COUPLE OF HRS...AND
THEN LINGER THRU THE EVENING. VFR CONDITIONS SHOULD BE THE RULE AT
ALL TERMINALS LATE TONIGHT THRU WED MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 426 PM EST TUE JAN 27 2015
WINDS WILL REMAIN UNDER 20KT TONIGHT/WED. LOW PRES WILL THEN TRACK
FROM THE MID AND UPPER MISSISSIPPI VALLEY WED EVENING TO THE LOWER
LAKES BY LATE THU EVENING. AHEAD OF THE LOW...S WINDS WILL INCREASE
FOR A TIME WED NIGHT...MAINLY OVER ERN LAKE SUPERIOR WHERE WINDS
WILL REACH 20-30KT. BEHIND THE LOW ON THU...N TO NW WINDS WILL
INCREASE TO 20-30KT OVER WRN LAKE SUPERIOR. OVER THE CNTRL AND ERN
LAKE...WINDS WILL INCREASE TO GALE FORCE FOR THU AFTN AND NIGHT.
COMBINATION OF MUCH COLDER AIR/STRONG WINDS AND BUILDING WAVES WILL
LEAD TO HVY FREEZING SPRAY THU AFTN UNTIL LATE FRI MORNING WHEN
WINDS/WAVES DIMINISH WITH THE CLOSER APPROACH OF CANADIAN HIGH PRES.
AFTER A PERIOD OF LIGHTER WINDS MOSTLY UNDER 20KT FRI INTO SAT
MORNING...N WINDS WILL INCREASE TO 20-30KT LATER SAT INTO SUN
IN THE WAKE OF A LOW PRES TROUGH.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
313 PM EST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EST TUE JAN 27 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN HI AMPLITUDE RDG OVER THE ROCKIES AND DEEP TROF
OVER THE E SUPPORTING INTENSE WINTER STORM THAT IS IMPACTING NEW
ENGLAND. SHRTWV DIGGING SEWD WITHIN THIS NW FLOW/DEEPER CLDS THAT
CAUSED PERIOD OF SN LAST EVNG ARE NOW SE OF THE AREA...SO LINGERING
LIGHT SN OVER THE CENTRAL CWA IS DIMINISHING WITH THE APRCH OF
SHRTWV RDG AXIS/DNVA/DEEP LYR QVECTOR CNVGC AND DRIER MID LVL AIR
SHOWN ON THE 00Z INL/YPL RAOBS. THESE RAOBS SHOW SOME LLVL MSTR BLO
INVRN...SO PLENTY OF LO CLDS LINGER UPSTREAM OVER NRN MN/NW ONTARIO.
HOWEVER...WITH 00Z H85 TEMP ONLY -5C AT INL...THE INCOMING AIRMASS
IS NOT SUFFICIENTLY COLD TO SUPPORT LES. COLDER AND DRIER LLVL AIR
IS STILL PRESENT TOWARD THE E AND ARCTIC HI PRES IN QUEBEC...WITH
MOCLR SKIES REPORTED EARLY THIS MRNG AT NEWBERRY AND THE SAULT.
MAIN FCST CONCERNS FOR TODAY/TNGT WL BE CLD TRENDS/IMPACT ON TEMPS.
TODAY...UPR MI WL BE DOMINATED BY DNVA/DEEP LYR QVECTOR DVGC
ASSOCIATED WITH APRCHG SHRTWV RDG. SO AFTER ANY LINGERING LIGHT SN
ENDS EARLY THIS MRNG...THE DAY SHOULD BE DRY AS SFC RDG AXIS
EXTENDING WSW FM THE HI CENTER IN QUEBEC SHIFTS OVER THE CWA.
DESPITE THE MID LVL DRYING...LINGERING LLVL MSTR TRAPPED BLO
LOWERING/STRENGTHENING SUBSIDENCE INVRN WL LIKELY MAINTAIN GENERALLY
MOCLDY SKIES...IN LINE WITH UPSTREAM OBS. ONE EXCEPTION SHOULD BE
THE ERN CWA...WHERE LIGHT E WIND WL MAINTAIN THE LLVL DRY AIR AND
ALLOW FOR MOSUNNY SKIES. ANOTHER AREA THAT MAY SEE SOME CLRG IS NEAR
LK SUP OVER THE NW CWA WHERE THE LLVL SW FLOW ON THE NRN FLANK OF
THE SFC RDG AXIS WL DOWNSLOPE AND RESULT IN LOWERING THE INVRN BASE
FURTHER. GOING FCST HI TEMPS MAINLY IN THE 20S...COLDEST OVER THE
E AND WARMEST OVER THE W...LOOK TO BE IN GOOD SHAPE.
TNGT...A SHRTWV IS FCST TO TRACK THRU FAR NRN ONTARIO. ALTHOUGH
LINGERING SHRTWV RDG AXIS WL FORCE THIS DISTURBANCE TO PASS TOO FAR
TO THE N TO BRING PCPN TO ALL BUT FAR NRN LK SUP LATE...AN INCRSG
LLVL ACYC SW FLOW BTWN THE SFC RDG AXIS SLIDING OVER LOWER MI AND
FALLING MSLP IN ONTARIO ASSOCIATED WITH THE PASSING SHRTWV WL ADVECT
SOME DRIER AIR INTO THE CWA. THIS DRYING PLUS MORE LLVL SUBSIDENCE
ASSOCIATED WITH THE STRENGTHENING ACYC FLOW WL LIKELY BREAK UP THE
LO CLDS OVER MUCH OF THE CWA...ESPECIALLY OVER NW NEAR LK SUP WHERE
SW WINDS DOWNSLOPE. OVER THE E...THE SW FLOW OFF LK MI MIGHT DRAW
MORE LO CLDS INTO THAT AREA. DESPITE ANY CLRG OF THE LOWER CLDS...
STRONGER WINDS AND INCRSG MID/HI CLDS ON THE SRN FLANK OF THE
DISTURBANCE PASSING TO THE N WL LIMIT THE DIURNAL TEMP FALL. EXPECT
THE LOWEST MIN TEMPS OVER THE E...WHERE TEMPS WL FALL OFF QUICKLY IN
THE EVNG BEFORE THE WINDS HAVE A CHC TO PICK UP A BIT OR ANY
CLDS ROLL IN LATER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 313 PM EST TUE JAN 27 2015
AN UPPER RIDGE OVER THE WESTERN COAST OF NORTH AMERICA AND AN UPPER
LOW OVER HUDSON BAY WILL KEEP NORTHWEST FLOW OVER THE UPPER GREAT
LAKES REGION FOR MUCH OF THE LONG TERM PERIOD. THIS WILL LEAD TO
SEVERAL SHORTWAVES DROPPING SOUTHEAST ACROSS THE REGION...WHILE THE
UPPER LOW OVER HUDSON BAY GRADUALLY SINKS SOUTH TOWARDS THE AREA.
THUS...EXPECT GRADUALLY COOLING TEMPERATURES THROUGH EARLY NEXT
WEEK.
THREE PIECES OF ENERGY WITHIN THE LARGER SHORTWAVE TROUGH MOVING
THROUGH THE UPPER GREAT LAKES REGION WEDNESDAY NIGHT AND THURSDAY
WILL BE DRIVING THE WEATHER FOR THE START OF THE LONG TERM PERIOD.
THE SOUTHERN TWO WAVES WILL BE SUPPORTING THE SURFACE LOW MOVING
THROUGH SOUTHERN WISCONSIN AND THE INVERTED TROUGH CROSSING THE
UPPER GREAT LAKES REGION. AT THE START OF THE LONG TERM
PERIOD...EXPECT THE HEAVIEST PRECIPITATION TO BE ONGOING OVER
NORTHERN ONTARIO AND FAR NORTHERN LAKE SUPERIOR...WHILE THERE WILL
BE SOME SNOW OVER EASTERN UPPER MICHIGAN TIED TO THE NOSE OF THE
850-700MB WARM AIR ADVECTION INTERACTING WITH THE DEEPER MOISTURE.
THINKING MUCH OF THE REST OF THE AREA WILL BE SEEING LIMITED
PRECIPITATION CHANCES WITH THE POCKET OF DRY AIR BETWEEN 925-750MB.
THEN AS THE 850-700MB TROUGH SWEEPS SOUTHEAST THROUGH THE AREA
THROUGH THE NIGHT...EXPECT SNOW TO QUICKLY SPREAD INTO THE AREA
THROUGH THE EVENING/OVERNIGHT HOURS. WITH THAT INITIAL PRECIPITATION
STAYING TO THE NORTH OF THE LAND AREA INITIALLY...HAVE TRENDED
QPF/SNOW AMOUNTS DOWN SLIGHTLY OVER THE WEST/CENTRAL (1-2IN).
NORTHEAST OF A LINE FROM HOUGHTON TO MANISTIQUE...HAVE AMOUNTS IN
THE 2-3.5 INCH RANGE AND WILL CONTINUE TO MENTION IN THE HWO FOR
THOSE AREAS. AS THE DEEPER MOISTURE DEPARTS THURSDAY
MORNING...WILL SEE THE SNOW DIMINISH...BUT THINK THERE WILL BE
ENOUGH TERRAIN INFLUENCE TO HELP KEEP SNOW SHOWERS IN THE
NORTH-NORTHWESTERLY WIND SNOW BELTS UNTIL THE COLD AIR ARRIVES
THURSDAY AFTERNOON AND INCREASES DELTA-T VALUES TOWARDS THE LOW 20S
BY THURSDAY EVENING. THERE ARE HINTS OF LIMITED ICE CRYSTALS (AND
THUS FREEZING DRIZZLE) OVER THE WEST AS THAT DEEP MOISTURE
DEPARTS...BUT THINK IT IS TOO MARGINAL TO MENTION AT THIS POINT.
WITH THAT COLD AIR ARRIVING FROM NORTHWEST TO SOUTHEAST ON THURSDAY
AFTERNOON/EVENING...SHOULD SEE LAKE EFFECT COVERAGE INCREASING
DURING THAT TIME FRAME. WILL TREND POPS UP TO LIKELY/DEFINITE VALUES
FOR THE FAVORED NORTHWEST WIND SNOW BELTS FOR THURSDAY NIGHT. WHILE
SNOW IS EXPECTED...THERE ARE A COUPLE LIMITING FACTORS FOR HIGHER
SNOWFALL AMOUNTS. FIRST...THE APPROACHING HIGH PRESSURE RIDGE WILL
KEEP THE SUBSIDENCE INVERSION AROUND 5KFT THROUGH THE PERIOD. WHILE
MUCH OF THE CLOUD WILL BE IN OR JUST ABOVE THE DGZ...THINK THE
FRACTURING OF THE FLAKES FROM THE GUSTY WINDS WILL KEEP SNOW RATIOS
LOWER (BUT BE BETTER AT REDUCING VISIBILITIES). THUS...HAVE
SNOWFALL AMOUNTS OF 1-4 INCHES IN THE FAVORED SNOW BELTS DURING THAT
PERIOD. AS THE HIGH MOVES JUST SOUTH OF THE AREA ON FRIDAY...EXPECT
WINDS TO BACK TOWARDS THE WEST AND LOWER THE SUBSIDENCE INVERSION
TOWARDS 4KFT. THEREFORE...WILL GRADUALLY DIMINISH PRECIPITATION
CHANCES THROUGH FRIDAY AS WINDS BACK TO THE SOUTHWEST ON FRIDAY
NIGHT.
THE NEXT CLIPPER WILL SWEEP ACROSS THE AREA SATURDAY AND DRAG A WEAK
SURFACE TROUGH WITH IT. STILL SOME DIFFERENCES IN THE TIMING WITH
THIS FEATURE...SO WILL GO WITH LOW END CHANCE POPS SPREADING ACROSS
THE CWA ON SATURDAY. OVERALL...LOOKS LIKE JUST A QUICK DUSTING OF
SNOW WITH THIS FEATURE. BEHIND THE TROUGH...COLD AIR WILL FILTER
BACK INTO THE UPPER GREAT LAKES REGION AND BRING ANOTHER PERIOD OF
LAKE EFFECT FOR THE NORTH-NORTHWEST WIND SNOWBELTS. ONCE AGAIN...THE
HIGH PRESSURE RIDGE NOSING EAST INTO THE AREA WILL KEEP THE
SUBSIDENCE INVERSION AROUND 5KFT AND KEEP THE LAKE EFFECT AMOUNTS ON
THE LIGHT SIDE. ONE ITEM TO WATCH IS THE POTENTIAL FOR A WEAK
SHORTWAVE SLIDING ACROSS THE AREA ON MONDAY. THERE ARE HINTS THAT
THIS MAY RAISE INVERSION HEIGHTS TOWARDS 7-10KFT...WHICH WOULD
PROVIDE THE POTENTIAL FOR MODERATE LAKE EFFECT. WHEN THAT
OCCURS...WITH ANOTHER SURGE OF COLD AIR (850MB TEMPS FALLING TO THE
MID -20S) THE CLOUD WILL BE WELL ABOVE THE DGZ AND SUPPORT SMALL
FLAKES THAT ARE HIGHLY EFFICIENT AT REDUCING VISIBILITY. WITH THE
HIGH MOVING SOUTHEAST FROM THE NORTHERN PLAINS ON MONDAY MORNING TO
THE OHIO RIVER VALLEY ON TUESDAY...EXPECT GRADUALLY BACKING WINDS
OVER LAKE SUPERIOR AND WILL FOLLOW THAT IDEA FOR AT LEAST LIKELY
POPS FOR THE FAVORED WIND DIRECTIONS THROUGH TUESDAY (WINDS NEAR
WESTERLY BY TUESDAY EVENING). WON/T MENTION IN THE HWO AT THIS
POINT...AS AMOUNTS WILL BE ON THE LOW SIDE...BUT MAY NEED TO ADDRESS
THE END OF THE WEEK LAKE EFFECT AND THE SUN-TUE LAKE EFFECT IN THE
FUTURE DUE TO THE LIKELY LOW VISIBILITIES IN THE STRONGER BANDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1238 PM EST TUE JAN 27 2015
LINGERING LOW CLOUDS WILL BE SLOW TO EXIT OVER MUCH OF THE W HALF OF
UPPER MI THIS AFTN/EVENING UNDER LIGHT WIND FIELDS. AT KIWD/KSAW...
MVFR CIGS ARE LIKELY TO LINGER INTO THE EVENING. SLIGHT
STRENGTHENING OF DOWNSLOPE WIND SHOULD ALLOW MVFR CIGS TO SCATTER
OUT AT KIWD LATE THIS EVENING. IT MAY NOT BE UNTIL OVERNIGHT THAT
MVFR CIGS SCATTER OUT AT KSAW. RECENT VIS SATELLITE IMAGERY SHOWS
GRADUAL EXPANSION OF LOWER CLOUDS TOWARD KCMX. SO...IT APPEARS MVFR
CIGS WILL LIKELY DEVELOP AT KCMX IN THE NEXT COUPLE OF HRS...AND
THEN LINGER THRU THE EVENING. VFR CONDITIONS SHOULD BE THE RULE AT
ALL TERMINALS LATE TONIGHT THRU WED MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST TUE JAN 27 2015
EXPECT S TO SW WINDS UNDER 20 KTS TO DOMINATE THRU WED AS A HI PRES
RIDGE OVER UPPER MI TODAY SINKS SLOWLY INTO THE LOWER GREAT LAKES.
ON THE NORTHERN FLANK OF A HI PRES RIDGE ORIENTED ACROSS THE CENTRAL
GREAT LAKES. LO PRES WILL THEN TRACK FROM THE MID MISSISSIPPI VALLEY
WED NIGHT TO THE LOWER LAKES THU NIGHT. BEHIND THE LOW...N TO NW
WINDS WILL INCREASE TO 20-30KT AND THEN TO GALE FORCE LATE THU AND
THU NIGHT. SINCE THESE STRONG WINDS WILL DRAW MUCH COLDER ARCTIC AIR
INTO THE UPPER LAKES...HEAVY FREEZING SPRAY WILL DEVELOP OVER MUCH
OF THE LAKE AND CONTINUE INTO FRI...WHEN WINDS/WAVES WILL DIMINISH
WITH THE CLOSER APPROACH OF CANADIAN HI PRES. ANOTHER DISTURBANCE
AND COLD FRONT MAY SWING ACROSS THE UPPER LAKES ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1238 PM EST TUE JAN 27 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EST TUE JAN 27 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN HI AMPLITUDE RDG OVER THE ROCKIES AND DEEP TROF
OVER THE E SUPPORTING INTENSE WINTER STORM THAT IS IMPACTING NEW
ENGLAND. SHRTWV DIGGING SEWD WITHIN THIS NW FLOW/DEEPER CLDS THAT
CAUSED PERIOD OF SN LAST EVNG ARE NOW SE OF THE AREA...SO LINGERING
LIGHT SN OVER THE CENTRAL CWA IS DIMINISHING WITH THE APRCH OF
SHRTWV RDG AXIS/DNVA/DEEP LYR QVECTOR CNVGC AND DRIER MID LVL AIR
SHOWN ON THE 00Z INL/YPL RAOBS. THESE RAOBS SHOW SOME LLVL MSTR BLO
INVRN...SO PLENTY OF LO CLDS LINGER UPSTREAM OVER NRN MN/NW ONTARIO.
HOWEVER...WITH 00Z H85 TEMP ONLY -5C AT INL...THE INCOMING AIRMASS
IS NOT SUFFICIENTLY COLD TO SUPPORT LES. COLDER AND DRIER LLVL AIR
IS STILL PRESENT TOWARD THE E AND ARCTIC HI PRES IN QUEBEC...WITH
MOCLR SKIES REPORTED EARLY THIS MRNG AT NEWBERRY AND THE SAULT.
MAIN FCST CONCERNS FOR TODAY/TNGT WL BE CLD TRENDS/IMPACT ON TEMPS.
TODAY...UPR MI WL BE DOMINATED BY DNVA/DEEP LYR QVECTOR DVGC
ASSOCIATED WITH APRCHG SHRTWV RDG. SO AFTER ANY LINGERING LIGHT SN
ENDS EARLY THIS MRNG...THE DAY SHOULD BE DRY AS SFC RDG AXIS
EXTENDING WSW FM THE HI CENTER IN QUEBEC SHIFTS OVER THE CWA.
DESPITE THE MID LVL DRYING...LINGERING LLVL MSTR TRAPPED BLO
LOWERING/STRENGTHENING SUBSIDENCE INVRN WL LIKELY MAINTAIN GENERALLY
MOCLDY SKIES...IN LINE WITH UPSTREAM OBS. ONE EXCEPTION SHOULD BE
THE ERN CWA...WHERE LIGHT E WIND WL MAINTAIN THE LLVL DRY AIR AND
ALLOW FOR MOSUNNY SKIES. ANOTHER AREA THAT MAY SEE SOME CLRG IS NEAR
LK SUP OVER THE NW CWA WHERE THE LLVL SW FLOW ON THE NRN FLANK OF
THE SFC RDG AXIS WL DOWNSLOPE AND RESULT IN LOWERING THE INVRN BASE
FURTHER. GOING FCST HI TEMPS MAINLY IN THE 20S...COLDEST OVER THE
E AND WARMEST OVER THE W...LOOK TO BE IN GOOD SHAPE.
TNGT...A SHRTWV IS FCST TO TRACK THRU FAR NRN ONTARIO. ALTHOUGH
LINGERING SHRTWV RDG AXIS WL FORCE THIS DISTURBANCE TO PASS TOO FAR
TO THE N TO BRING PCPN TO ALL BUT FAR NRN LK SUP LATE...AN INCRSG
LLVL ACYC SW FLOW BTWN THE SFC RDG AXIS SLIDING OVER LOWER MI AND
FALLING MSLP IN ONTARIO ASSOCIATED WITH THE PASSING SHRTWV WL ADVECT
SOME DRIER AIR INTO THE CWA. THIS DRYING PLUS MORE LLVL SUBSIDENCE
ASSOCIATED WITH THE STRENGTHENING ACYC FLOW WL LIKELY BREAK UP THE
LO CLDS OVER MUCH OF THE CWA...ESPECIALLY OVER NW NEAR LK SUP WHERE
SW WINDS DOWNSLOPE. OVER THE E...THE SW FLOW OFF LK MI MIGHT DRAW
MORE LO CLDS INTO THAT AREA. DESPITE ANY CLRG OF THE LOWER CLDS...
STRONGER WINDS AND INCRSG MID/HI CLDS ON THE SRN FLANK OF THE
DISTURBANCE PASSING TO THE N WL LIMIT THE DIURNAL TEMP FALL. EXPECT
THE LOWEST MIN TEMPS OVER THE E...WHERE TEMPS WL FALL OFF QUICKLY IN
THE EVNG BEFORE THE WINDS HAVE A CHC TO PICK UP A BIT OR ANY
CLDS ROLL IN LATER.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 502 AM EST TUE JAN 27 2015
MUCH OF THIS PERIOD WILL BE IMPACTED BY THE STEADY 500MB LOW OVER E
AND E CANADA. FROM TIME TO TIME IT WILL BE EXTENDING A TROUGH ACROSS
MUCH OF THE E HALF OF THE U.S.
WARMEST DAY THIS PERIOD WILL BE WEDNESDAY...WITH HIGHS GENERALLY 30-
35F ON LIGHT S FLOW. A LOW OVER N HUDSON BAY AND AN ADDITIONAL LOW
ACROSS THE N/CENTRAL PLAINS WILL PUSH A TROUGH OVER LAKE SUPERIOR
WEDNESDAY NIGHT. THIS WILL BRING THE BEST CHANCE OF WIDESPREAD SNOW
THROUGH THE LONG TERM PERIOD. HAVE ADJUSTED THE HWO MESSAGE TO
INCLUDE MAINLY THE TIP OF THE KEWEENAW AND E OF A LINE FROM MQT TO
ESC FOR THE POTENTIAL FOR MODERATE SNOW AMOUNTS. EXACT AMOUNTS VARY
SIGNIFICANTLY DEPENDING ON WHAT MODEL IS USED. FOR EXAMPLE AT KSAW
FOR WEDNESDAY NIGHT BUFKIT IS INDICATING THE POTENTIAL FOR 1-2IN
/00Z AND 06Z MODEL RUNS/. THE GFS IS SHOWING CLOSER TO 4-6IN. TAKING
A LOOK AT THE PRECIP FIELDS...THE 27/00Z ECMWF ALIGNS BETTER WITH
THE NAM WHILE THE CANADIAN IS CLOSER TO THE GFS. WILL CONTINUE A
FCST OF 2-5IN FOR MUCH OF THE CWA FROM WED THROUGH THURSDAY...WITH
ONLY 1-2IN ALONG THE WI BORDER. ONLY LIMITED SNOW IS EXPECTED OVER
THE UPSLOPE N CENTRAL AND E LOCATIONS BAST WEDNESDAY NIGHT/THURSDAY
MORNING.
THE TROUGH WILL WEAKEN THURSDAY/THURSDAY NIGHT AS THE LOW ACROSS THE
PLAINS SHIFTS TO S LOWER MI...AND THE NEW ENGLAND STATES.
HOWEVER...INCREASED N-NNW WINDS THURSDAY AFTERNOON LOOK
REASONABLE...WITH A 30-40KT LLJ SET UP...EXPECT ABOVE 925MB. THIS
WILL BE AS UPPER MI BECOMES STUCK BETWEEN THE EXITING LOW PUSHING
TOWARDS THE LOWER GREAT LAKES AND STRONG HIGH PRESSURE NEARING FROM
THE W. LOOK FOR PATCHY BLOWING SNOW TO DEVELOP THURSDAY ALONG LAKE
SUPERIOR...REDUCING VIS.
FRIDAY INTO EARLY SATURDAY... EXPECT THE HIGH MENTIONED ABOVE OVER
SASKATCHEWAN ON THURSDAY TO SINK ACROSS MN AND W LAKE SUPERIOR
FRIDAY MORNING...AND INTO THE OHIO VALLEY AND MID ATLANTIC STATES
SATURDAY. COLD AIR WILL BE OVERHEAD...WITH HIGHS IN THE LOW TO MID
TEENS FRIDAY. WHILE LOW LEVEL MOISTURE AROUND 800MB AND BELOW WILL
REMAIN TRAPPED UNDER THE LOWERING INVERSION THURSDAY-FRIDAY...AND
THE DGZ WILL BE WITHIN THIS MOISTURE LAYER...NO HEADLINE LES IS
ANTICIPATED. THIS WILL BE EVEN THROUGH SLR VALUES CLIMB BACK TO 20-
25:1. LESS THAN FAVORABLE W-SW WINDS FRIDAY EVENING SHOULD PUSH MUCH
IF NOT ALL OF THE LINGERING LIGHT SNOW SHOWERS BACK INTO LAKE
SUPERIOR. THE DRY WEATHER WILL ONLY BE TEMPORARY.
REST OF SATURDAY... A BRIEF TROUGH OF LOW PRESSURE WILL PUSH ACROSS
LAKE SUPERIOR ON SATURDAY...BEFORE STRONGER HIGH PRESSURE NEARS FROM
CENTRAL CANADA. TIMING THIS TROUGH IS IS STILL A BIT ROUGH...AS THE
GFS/ECMWF/CANADIAN DIFFER BY 6-12HRS. THE 27/00Z CANDIAN AND 26/12Z
ECMWF ARE PRETTY CONSISTANT...WHILE THE 27/00Z GFS IS ON THE SLOW
SIDE. EITHER WAY IT WILL USHER IN ANOTHER ROUND OF COLD AIR. HIGHS
SUNDAY SHOULD TOP OUT 10-17F.
SUNDAY THROUGH MONDAY... STRONGER AND COLD 30.9 INCH/1040-1050MB
HIGH PRESSURE OVER MUCH OF CENTRAL CANADA FRIDAY AND SATURDAY WILL
SLOWLY WEAKEN TO 30.6IN/1033-1037MB AS IT SETTLES ACROSS THE N
PLAINS/ UPPER MS VALLEY/UPPER GREAT LAKES TO START THE NEXT WORK
WEEK. HIGHS MONDAY MAY ONLY BE IN THE SINGLE DIGITS ABOVE ZERO.
THE HIGH WILL CONTINUE TO SINK SE ACROSS THE MID MS VALLEY/OHIO
VALLEY MONDAY NIGHT...AND MID ATLANTIC STATES TUESDAY-WEDNESDAY. THE
GFS IS PERSISTENT IN KEEPING THE HIGH IN PLACE...WHILE THE 26/12Z
ECMWF IS MORE PROGRESSIVE. MORE ON THIS WHEN WE START FCSTING FOR
MID NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1238 PM EST TUE JAN 27 2015
LINGERING LOW CLOUDS WILL BE SLOW TO EXIT OVER MUCH OF THE W HALF OF
UPPER MI THIS AFTN/EVENING UNDER LIGHT WIND FIELDS. AT KIWD/KSAW...
MVFR CIGS ARE LIKELY TO LINGER INTO THE EVENING. SLIGHT
STRENGTHENING OF DOWNSLOPE WIND SHOULD ALLOW MVFR CIGS TO SCATTER
OUT AT KIWD LATE THIS EVENING. IT MAY NOT BE UNTIL OVERNIGHT THAT
MVFR CIGS SCATTER OUT AT KSAW. RECENT VIS SATELLITE IMAGERY SHOWS
GRADUAL EXPANSION OF LOWER CLOUDS TOWARD KCMX. SO...IT APPEARS MVFR
CIGS WILL LIKELY DEVELOP AT KCMX IN THE NEXT COUPLE OF HRS...AND
THEN LINGER THRU THE EVENING. VFR CONDITIONS SHOULD BE THE RULE AT
ALL TERMINALS LATE TONIGHT THRU WED MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EST TUE JAN 27 2015
EXPECT S TO SW WINDS UNDER 20 KTS TO DOMINATE THRU WED AS A HI PRES
RIDGE OVER UPPER MI TODAY SINKS SLOWLY INTO THE LOWER GREAT LAKES.
ON THE NORTHERN FLANK OF A HI PRES RIDGE ORIENTED ACROSS THE CENTRAL
GREAT LAKES. LO PRES WILL THEN TRACK FROM THE MID MISSISSIPPI VALLEY
WED NIGHT TO THE LOWER LAKES THU NIGHT. BEHIND THE LOW...N TO NW
WINDS WILL INCREASE TO 20-30KT AND THEN TO GALE FORCE LATE THU AND
THU NIGHT. SINCE THESE STRONG WINDS WILL DRAW MUCH COLDER ARCTIC AIR
INTO THE UPPER LAKES...HEAVY FREEZING SPRAY WILL DEVELOP OVER MUCH
OF THE LAKE AND CONTINUE INTO FRI...WHEN WINDS/WAVES WILL DIMINISH
WITH THE CLOSER APPROACH OF CANADIAN HI PRES. ANOTHER DISTURBANCE
AND COLD FRONT MAY SWING ACROSS THE UPPER LAKES ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
346 PM EST TUE JAN 27 2015
.SYNOPSIS...
A STRONG COASTAL LOW PRESSURE EAST OF CAPE COD WILL
SLOWLY MOVE AWAY FROM THE REGION TONIGHT...WITH AREAS OF SNOW
TAPERING OFF TO SCATTERED FLURRIES BY WEDNESDAY MORNING. IN
ADDITION...GUSTY NORTH WINDS WILL SLOWLY DECREASE AS SURFACE HIGH
PRESSURE BUILDS INTO THE REGION. A FAST MOVING CLIPPER LIKE SYSTEM
WILL IMPACT THE NORTH COUNTRY LATE THURSDAY INTO FRIDAY WITH ANOTHER
ROUND OF LIGHT ACCUMULATING SNOW LIKELY. TEMPERATURES WILL START
BELOW NORMAL...BUT WARM TO NEAR NORMAL LEVELS BY THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 345 PM EST TUESDAY...AVE CANCELLED WINTER STORM WARNING AND
REPLACED WITH WINTER WX ADVISORY FOR SNOW AND BLOWING SNOW.
ALSO...EXPANDED ADVISORY TO COVER PARTS OF THE CHAMPLAIN AND
WESTERN SLOPES FOR THE COMBINATION SNOW AND BLOWING SNOW THROUGH
THE EVENING COMMUTE. EXPECTING A DIFFICULT EVENING COMMUTE ACROSS
MOST THE REGION. BTV PICKED UP 3 INCHES OF SNOW IN JUST SEVERAL
HRS UNDER THIS BAND OF HEAVY SNOW THIS AFTN. EXPECTING ADDITIONAL
ACCUMULATIONS OF 1 TO 3 WITH LOCALIZED HIGHER AMOUNTS UNDER THIS
NARROW MESO BAND OF MODERATE SNOW ACRS PORTIONS OF THE CHAMPLAIN
AND WESTERN SLOPES.
FCST CHALLENGE TONIGHT WL BE AREAL COVERAGE/INTENSITY OF SNOW THRU
MIDNIGHT...ESPECIALLY FOR THE CHAMPLAIN VALLEY AND PARTS OF GREEN
MTNS. CRNT WATER VAPOR SHOWS DEEP CLOSED CYCLONIC CIRCULATION JUST
EAST OF CAPE COD THIS AFTN...WITH SEVERAL BAND OF MID/UPPER LVL
MOISTURE ROTATING BACK TOWARD OUR CWA. WATER VAPOR AND RAP SHOWS
THIS MID LVL MOISTURE AND ELONGATED 5H VORTICITY MAXIMUM WL BECOME
STATIONARY ACRS THE CHAMPLAIN VALLEY/CENTRAL VT THIS
AFTN/EVENING...WITH OCCASIONAL SNOW LINGERING THRU THE EVENING HRS.
THIS SUPPORT ALOFT...COMBINED WITH FAVORABLE NORTHERLY FLW WL
ENHANCE CONVERGENCE ON THE EASTERN SIDE OF THE CHAMPLAIN
VALLEY...SUPPORTING LIGHT SNOW THRU 06Z...BEFORE TAPERING OFF TO
FLURRIES. IN ADDITION...NAM FROUDE NUMBER SHOWS BLOCKED FLW WITH
VALUES <0.50...SUPPORTING ENHANCED SNOWFALL ALONG AND UPSTREAM OF
THE GREEN MTNS INTO THE CHAMPLAIN VALLEY. WL TRY TO SHOW THIS DETAIL
IN THE GRIDS AND INCREASE THE SNOWFALL AMOUNTS SLIGHTLY ACRS THIS
REGION...THINKING BTWN 1 AND 4 INCHES...WITH ISOLATED HIGHER AMOUNTS
POSSIBLE. ELSEWHERE...AREAL COVERAGE OF MID LVL MOISTURE DECREASES
RAPIDLY THIS AFTN/EVENING...AND ADDITIONAL SNOWFALL WL BE LIMITED.
THIS IS ALREADY SUPPORTED BY RADAR SHOWING LARGE HOLE OF NO PRECIP
ACRS MOST OF THE CT RIVER VALLEY AND NEK OF VT. ADDITIONAL SNOWFALL
WL BE A DUSTING TO AN INCH OR TWO POSSIBLE IN THESE AREAS...WITH
ONLY FLURRIES FOR THE SAINT LAWRENCE VALLEY/WESTERN DACKS.
ALSO...EXPECT GUSTY NORTH WINDS TO CONTINUE...ESPECIALLY CHAMPLAIN
VALLEY WITH SOME ENHANCED CHANNELING...WHICH WL CAUSE AREAS OF
BLOWING AND DRIFTING SNOW. GUSTY TO 30 MPH WL BE LIKELY THRU 03Z
TONIGHT. TEMPS WL REMAIN NEARLY STEADY IN THE SINGLE DIGITS
ABOVE/BLW ZERO TO NEAR 10F MOST LOCATIONS.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 345 PM EST TUESDAY...SFC HIGH PRES BUILDS ACRS OUR CWA ON
WEDS...RESULTING IN A SLOW WEST TO EAST CLRING TREND. GFS/ECMWF
STILL SHOWS SOME LINGERING 850 TO 500MB RH ACRS OUR CENTRAL/EASTERN
CWA THRU 15Z...BEFORE SHIFTING IT EASTWARD. LARGE SCALE SUBSIDENCE
AND DEEP DRYING WL RESULT IN CLRING SKIES BY 18Z WEDS. NEXT FAST
MOVING CLIPPER LIKE SYSTEM ARRIVES LATE THURS INTO FRIDAY. LATEST
GUIDANCE TRACKS THIS SYSTEM ACRS OUR CWA...WHICH WL CAUSE A
WIDESPREAD LIGHT SNOW EVENT. EXPECTING AN ADVISORY LVL EVENT WITH
GENERAL ACCUMULATIONS OF 3 TO 5 INCHES...EXCEPT SLIGHTLY HIGHER
AMOUNTS OF 6 INCHES IN THE FAVORABLE UPSLOPE REGIONS. TEMPS WL
REBOUND TO NEAR NORMAL LEVELS AFTER A COLD START ON THURS MORNING.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 335 PM EST TUESDAY...AN ACTIVE PATTERN IS QUITE LIKELY FOR
THE PERIOD, WITH TWO OPPORTUNITIES FOR SNOW AND SEVERAL DAYS WITH
WELL BELOW NORMAL TEMPERATURES. GIVEN THE ONGOING WEATHER, AND
FOCUS NEEDED ON THAT, I RELIED RATHER HEAVILY ON A "DOWN THE
MIDDLE" MODEL BLEND FOR MOST OF THE FORECAST PERIOD, WITH ONLY A
FEW MANUAL MODIFICATIONS. FROM WHAT I SAW, THE 12Z SUITE OF GFS,
GFS ENSEMBLE AND ECMWF WERE ALL IN THE BALLPARK ENOUGH THAT A
BLEND SHOULD WORK OUT PRETTY GOOD.
DAILY DETAILS BELOW...
FRIDAY: CLIPPER WILL BE QUICKLY EXITING DURING THE DAY, AND AS IT
MOVES EAST OF HERE IT SHOULD STRENGTHEN ONCE IT REACHES THE
"WARMER" ATLANTIC OCEAN WATERS. NET RESULT WILL BE AN INCREASE IN
NORTHWEST WINDS -- COULD BE GUSTY AT TIMES. PAINTED IN SOME
20-30MPH GUSTS. THESE NORTHWEST WINDS WILL ALSO USHER IN COLDER
AIR AS THE DAY GOES ON. DEFINITELY A NON-DIURNAL TEMPERATURE TREND
WITH HIGHS FIRST THING. THE MID 20S "WARMTH" AT 8AM WILL END UP
IN THE 5-15F RANGE BY EVENING TIME. COULD HAVE SOME WIND CHILL
ISSUES TO TRACK COME FRIDAY/FRIDAY NIGHT. ON THE PRECIPITATION
SIDE OF THINGS, SNOW SHOWERS FIRST THING IN THE DAY WILL DIMINISH
AND BE MORE CONFINED TO THE MOUNTAINS BY AFTERNOON. IN THE END,
LOOKS LIKE A SOLID 3-5" "ADVISORY" LEVEL EVENT (LOCALLY A BIT MORE
IN THE NORTHERN MOUNTAINS). GENERALLY CLEAR AND COLD FRIDAY
NIGHT. SUB- ZERO FOR EVERYBODY!
SATURDAY: HIGH PRESSURE BUILDS IN. SHOULD BE SUNNY, BUT ALWAYS
BEWARE OF SUNNY DAYS IN MID-WINTER. THAT MEANS COLD TOO. 925MB
TEMPERATURES DOWN AROUND -20C. HIGHS 0 TO 8F WHERE WE LIVE. BRRR.
WARM WEATHER FANS WILL NEED TO LOOK AT THE SUNNY SKIES AND PRETEND
TO FEEL THE WARMTH. SATURDAY NIGHT - ANOTHER QUIET AND COLD NIGHT.
SUB-ZERO FOR US ALL AGAIN.
SUNDAY/MONDAY: FAST MOVING TROUGH IN THE UPPER FLOW WILL RESULT IN
CYCLOGENESIS IN THE OHIO VALLEY SUNDAY, FOLLOWED BY PERHAPS THE
DEVELOPMENT BY MONDAY OF A STRONG SURFACE LOW THAT WILL TRACK
SOMEWHERE JUST SOUTH OF HERE. GFS SUGGEST JUST SOUTH OF LONG
ISLAND. ECMWF IS A BIT FARTHER NORTH AND GOES ACROSS SOUTHERN NEW
ENGLAND. HAVE GONE AHEAD AND BUMPED POPS UP TO THE 50-60% RANGE
FOR SUNDAY NITE/MONDAY. CERTAINLY STILL A LOT OF UNCERTAINTY WITH
REGARD TO TRACK AND INTENSITY. AT THIS POINT LOOKS LIKE AN ALL
SNOW EVENT WITH LIKELY A PLOWABLE AMOUNT OF SNOW. HOWEVER, IF THE
TRACK ENDS UP GOING A LITTLE FURTHER NORTH, THEN WE MAY BE LOOKING
AT SOME MIXED PRECIPITATION ISSUES FOR PARTS OF THE FORECAST AREA.
AS MENTIONED, EARLIER, JUST WENT WITH MODEL BLENDS FOR
TEMPERATURES BUT ABOVE THE BLENDS FOR PRECIPITATION CHANCES.
TUESDAY: ANOTHER SHOT OF BITTER ARCTIC AIR IN THE WAKE OF THE
SUNDAY/MONDAY STORM. GFS IS BRUTALLY COLD. 925MB TEMPERATURES DOWN
TO -35C! THE RAW MODEL SURFACE TEMPERATURE COME TUESDAY MORNING IS
-25 TO -35F! (NOTE THAT MOS TURNS THAT INTO A -3F FOR BTV), AND
HIGH TEMPERATURES WOULD ONLY BE -5 TO -15F. THE ECMWF IS "MUCH"
WARMER -- 925MB TEMPERATURES OF -20C WITH IT`S RAW SURFACE
TEMPERATURES ABOUT -15F IN THE MORNING WITH HIGHS -5 TO +5F. AT
THIS POINT, HAVE MADE THE FORECAST CLOSER TO THE ECWMF.
I DID WANT TO MAKE THE 7TH DAY OF THE FORECAST TO SHOW A +1C FOR A
HIGH TEMPERATURE, JUST TO GIVE SOME HOPE TO WARM WEATHER FANS
AFTER DAYS OF SUB-FREEZING (< 0C) HIGHS. BUT ALAS, IT WASN`T
POSSIBLE.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...CONFIDENCE ON THE LOW SIDE FOR SPECIFIC
DETAILS IN THE TAFS FOR NOW THROUGH 03Z. JUST WANTED TO GET THAT
OUT THERE FIRST.
CURRENTLY, CONDITIONS RANGE FROM IFR/LIFR ACROSS MUCH OF VERMONT
TO VFR ACROSS MUCH OF NORTHERN NEW YORK. BANDS OF SNOW ARE SLOWLY
PUSHING FROM EAST TO WEST ACROSS VERMONT. IN SPOTS, THE SNOW DOES
BRIEFLY RESULT IN VISIBILITY REDUCTIONS DOWN TO 1/4SM, BUT IN
GENERAL IT`S MORE LIKE 3/4SM TO 1 1/2SM.
RADAR TRENDS SHOWING THE INITIAL BATCH OF SNOW IS DRYING UP AS IT
MOVES TOWARD NORTHERN NEW YORK. THERE IS UNCERTAINTY AS TO WHETHER
IT MAKES IT TO SLK, THOUGH IT APPEARS MSS WILL STAY VFR. RADAR
ALSO SHOWING A "BREAK IN THE ACTION" DEVELOPING ACROSS THE VT/NH
BORDER. IT COULD BE THAT THIS IS A SIGN THAT THE SNOW WONT LAST
ALL THAT LONG (6 HOURS OR SO) IN ANY SPOT. HOWEVER, SOME GUIDANCE
SUGGESTS LIGHT SNOW CONTINUES ALL THE WAY TO 12Z.
GAVE IT MY BEST SHOT. IN GENERAL GOING WITH THE IDEA THAT THE BULK
OF THE MODERATE SNOW & LOWEST VISIBILITIES WILL LAST UP TO 20-23Z
OR SO, WITH DIMINSHING SNOW THROUGH 03Z (AND MVFR CONDITIONS).
AFTER THAT, VFR SHOULD BE THE RULE. MAY END UP NEEDING TO AMEND
FORECASTS IF THE RADAR TRENDS INDICATE THE FORECASTS NEED SOME
FIXING.
NORTHERLY SURFACE WINDS WILL REMAIN GUSTY, ESPECIALLY IN THE
CHAMPLAIN VALLEY. 20-25KTS SHOULD BE COMMON. PERHAPS SOME LOWER
30KT GUSTS. THESE WINDS WILL DIMINISH BY LATE AFTERNOON. THOUGH
NOT EXPLICITLY SHOWN IN THE TAFS, MINOR BLOWING SNOW MAY OCCUR AS
WELL.
FROM 12Z WEDNESDAY ONWARD, LOOKS LIKE VFR CONDITIONS AREA WIDE.
OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY...
18Z WEDNESDAY THROUGH 00Z FRIDAY...VFR.
00Z FRIDAY THROUGH 00Z SATURDAY...MVFR/IFR IN PERIODS OF SNOW.
00Z SATURDAY ONWARD...VFR.
&&
.EQUIPMENT...
AS OF 122 PM EST MONDAY...THE KTYX 88D DOPPLER RADAR LOCATED NEAR
WATERTOWN NEW YORK WILL BE DOWN AT LEAST THROUGH TUESDAY. THIS IS
DUE TO A PEDESTAL DYNAMIC FAULT. ELECTRONICS TECHNICIANS HAVE
ORDERED NEW PARTS TO FIX THIS PROBLEM. HOWEVER...THE NEW PARTS
HAVE NOT ARRIVED AS OF THIS TIME AND THE KTYX RADAR WILL LIKELY
NOT BE RESTORED TO SERVICE UNTIL SOMETIME THIS WEEK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR
VTZ002>012-016>019.
NY...WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR NYZ035.
&&
$$
SYNOPSIS...TABER
NEAR TERM...TABER
SHORT TERM...TABER
LONG TERM...NASH
AVIATION...NASH
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1225 PM EST TUE JAN 27 2015
.SYNOPSIS...
STRONG COASTAL LOW PRESSURE WILL SPREAD WIDESPREAD LIGHT TO
MODERATE SNOWS ACROSS THE EASTERN HALF OF THE FORECAST AREA TODAY
INTO EARLY THIS EVENING. HIGH PRESSURE RETURNS FOR LATER TONIGHT
THROUGH EARLY THURSDAY WITH SEASONABLY COLD AND MAINLY DRY
WEATHER. MORE LIGHT SNOWS ARE EXPECTED BY THURSDAY NIGHT INTO
FRIDAY AS LOW PRESSURE TRACKS EAST FROM THE GREAT LAKES STATES.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 1214 PM EST TUESDAY...FCST REMAINS IN GOOD SHAPE THIS AFTN
WITH BAND OF MODERATE/HEAVY SNOW LIFTING ACRS CENTRAL VT
ATTM...WITH VIS AT MPV DOWN TO 1/4SM IN HEAVY SNOW. THIS BAND WL
SLOWLY SHIFT TWD THE CHAMPLAIN THRU THIS AFTN...WITH LIGHT TO
OCCASIONAL MODERATE SNOW EXPECT. CRNT RADAR SHOWS SNOW BREAKING UP
ACRS THE CT RIVER VALLEY...BUT EXPECT SOME ADDITIONAL LIGHT SNOW
THRU THE AFTN HOURS. HEADLINES REMAIN IN PLACE WITH STORM TOTAL
SNOW AMOUNTS RANGING FROM DUSTING TO 3 INCHES CHAMPLAIN
VALLEY/EASTERN DACKS TO 3 TO 6 INCHES CENTRAL VT...AND 5 TO 10
INCHES ACROSS RUTLAND/ORANGE AND WINDSOR COUNTIES. WL HAVE TO
WATCH POTENTIAL ENHANCEMENT HERE ACRS THE EASTERN CPV THRU THE
AFTN HOURS ASSOCIATED WITH NORTHERLY WINDS AND ADDITIONAL LLVL
MOISTURE COMING OFF LAKE CHAMPLAIN. LATEST RAP AND HRRR SHOW ONCE
THE MID/UPPER LVL BECOME SATURATED...THE SNOW MAY STICK AROUND
THRU 00Z THIS EVENING. ALSO...HAVE INCREASED WINDS ACRS THE
CHAMPLAIN VALLEY...AS WE ARE SEEING LOCALIZED ENHANCEMENT ON NORTH
FLW. COLCHESTER REEF SUBSTAIN AT 31 KNOTS AND DIAMOND ISLAND WAS
35 KNOTS EARLIER THIS MORNING. HAVE MENTION LOCALIZED GUSTS NEAR
THE LAKE AROUND 30 KNOTS OR SO.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
AS OF 321 AM EST TUESDAY...HIGH PRESSURE THEN BUILDS EAST INTO
THE REGION BY WEDNESDAY WITH SKIES TRENDING CLEAR TO PARTLY CLOUDY
THROUGH THE COURSE OF THE AFTERNOON. DRY WEATHER CONDITIONS
EXPECTED WITH BLENDED MOS NUMBERS SUPPORTING HIGH TEMPERATURES
GENERALLY IN THE TEENS...PERHAPS LOWER 20S FAR SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
AS OF 314 AM EST TUESDAY...DRY WEATHER TO START THE PERIOD AS
RIDGE OF HIGH PRESSURE AND ALOFT RESIDES OVER THE REGION WEDNESDAY
NIGHT. EARLY THURSDAY, THE RIDGE SLIDES EASTWARD WITH SOUTHERLY
FLOW DEVELOPING OVER THE REGION, INCREASING MOISTURE AND
MODERATING TEMPERATURES AHEAD OF A CLIPPER SYSTEM APPROACHING FROM
THE GREAT LAKES REGION. WHILE GFS AND ECMWF AGREE THAT
PRECIPITATION SHIELD WILL ENTER OUR WESTERN ZONES THURSDAY
AFTERNOON, THERE AREA DIFFERENCE REGARDING THE TRACK OF THE SFC
LOW AND THE PROGRESSION OF THE ASSOCIATED MID LEVEL TROUGH. THIS
LOW LOOKS TO BRING SNOW TO THE REGION THROUGH AT LEAST FRIDAY
EVENING. MID LEVEL TROUGH BECOMES NEGATIVELY TILTED ACCORDING TO
BOTH MODELS, THEREFORE AM FAVORING A SLOWER DEPARTURE OF
PRECIPITATION FROM NORTHEASTERN VERMONT AS DEPICTED BY THE ECMWF.
EXPECTING SOME LINGERING POPS INTO EARLY SATURDAY MORNING, BUT
NORTH/NORTHWEST FLOW BEHIND THIS SYSTEM WILL BRING IN DRIER AIR.
SO EXPECT SATURDAY TO BE MOSTLY DRY AT THIS POINT. AT THIS POINT,
EXPECT POTENTIAL SNOWFALL TOTALS TO RANGE FROM 2 TO 5 INCHES.
ANOTHER SYSTEM DEVELOPING IN THE MISSISSIPPI VALLEY WILL MOVE
NORTHEASTWARD LATE SUNDAY INTO MONDAY...BRINGING ANOTHER CHANCE
FOR SNOW FOR THE BEGINNING OF NEXT WEEK.
TEMPERATURES WEDNESDAY NIGHT WILL BE GENERALLY IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO. TEMPERATURES MODERATING IN THE
SOUTHERLY FLOW THURSDAY THROUGH FRIDAY WITH MAXES IN THE 20S AND
MINS IN THE TEENS TO L20S. BEHIND THE CLIPPER LOW, COLD AIR WILL
RETURN WITH MINS OF -15F TO ZERO FOR THE REST OF THE PERIOD. MAXES
WILL REACH SINGLE DIGITS TO MID TEENS SATURDAY THROUGH MONDAY.
&&
.AVIATION /17Z TUESDAY THROUGH SUNDAY/...
THROUGH 12Z WEDNESDAY...VFR CONDITIONS WILL DETERIORATE TO MVFR
AS SNOW SPREADS NORTHWESTWARD THIS MORNING. EXPECT MVFR
CONDITIONS AND SNOW TO MOVE INTO KRUT BETWEEN 12-15Z...KMPV 13-
15Z...KBTV/KPBG 15Z-17Z...AND KSLK 16Z-18Z. KMSS WILL BE FAR
ENOUGH NORTH AND WEST TO REMAIN VFR. SOME EMBEDDED MODERATE SNOW
IS POSSIBLE WITH IFR/LIFR CONDITIONS AFFECTING KRUT/KMPV 14Z-
22Z...KBTV/KPBG 17Z-21Z AND KSLK 18Z-23Z.
SNOW WILL LIGHTEN AND DIMINISH THIS EVENING WITH MOSTLY DRY
CONDITIONS SETTLING IN AFTER MIDNIGHT/05Z. EXPECT CONDITIONS TO
IMPROVE TO MVFR/VFR AS SNOWFALL COMES TO AN END.
NORTH TO NORTHEAST WINDS OF 6-12KTS WILL INCREASE AND BECOME
GUSTY AROUND 25KTS BY MID MORNING. THIS WILL RESULT IN THE
POTENTIAL FOR AREAS OF BLOWING/DRIFTING SNOW, ESPECIALLY AT RUT
AND MPV WHERE DURATION OF MODERATE SNOW WILL BE LONGEST. EXPECT
GUSTS TO SUBSIDE HEADING INTO TUESDAY EVENING.
OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY...
12Z WEDNESDAY THROUGH 12Z THURSDAY...MAINLY VFR CONDITIONS
EXPECTED AS RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
12Z THURSDAY THROUGH 00Z SATURDAY...TRENDING IFR/MVFR IN LIGHT
SNOW AS LOW PRESSURE MOVES EAST FROM THE OHIO VALLEY/GREAT LAKES
STATES.
00Z SATURDAY THROUGH 00Z SUNDAY...VFR CONDITIONS EXPECTING AS A
RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION.
&&
.EQUIPMENT...
AS OF 122 PM EST MONDAY...THE KTYX 88D DOPPLER RADAR LOCATED NEAR
WATERTOWN NEW YORK WILL BE DOWN AT LEAST THROUGH TUESDAY. THIS IS
DUE TO A PEDESTAL DYNAMIC FAULT. ELECTRONICS TECHNICIANS HAVE
ORDERED NEW PARTS TO FIX THIS PROBLEM. HOWEVER...THE NEW PARTS
HAVE NOT ARRIVED AS OF THIS TIME AND THE KTYX RADAR WILL LIKELY
NOT BE RESTORED TO SERVICE UNTIL SOMETIME THIS WEEK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER STORM WARNING UNTIL 1 AM EST WEDNESDAY FOR VTZ010>012-
019.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR VTZ004-
007>009-018.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...TABER
SHORT TERM...JMG
LONG TERM...KGM
AVIATION...KGM
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1045 AM CST TUE JAN 27 2015
.UPDATE...
ISSUED AT 1040 AM CST TUE JAN 27 2015
HAVE UPDATED THE FORECAST FOR THIS MORNING TO ISSUE A DENSE FOG
ADVISORY. SOUTHEAST FLOW ACROSS THE AREA MAKING IT DIFFICULT FOR
STRATUS TO ERODE ACROSS THE AREA. WINDS EXPECTED TO INCREASE
THROUGHOUT THE DAY...BUT STILL MAY NOT BE ENOUGH TO SCOUR OUT THE
CLOUDS. HAVE LOWERED FORECAST HIGHS FOR TODAY...ESPECIALLY IN THE
EAST.
FOR TONIGHT...NAM SHOWS THE STRATUS THICKENING WHILE THE RAP SHOWS
THE STRATUS THINNING AS WINDS INCREASE. IF THE STRATUS GETS THICK
ENOUGH...MAY NEED TO CONSIDER DRIZZLE BUT WILL TAKE A LOOK AT THAT
FOR THE AFTERNOON PACKAGE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 257 AM CST TUE JAN 27 2015
ONLY AREA OF STRATUS VERY EARLY THIS MORNING IS SITUATED THROUGH
PORTIONS OF SOUTHWESTERN MINNESOTA INTO THE IOWA GREAT LAKES
AREA...WITH SOME PATCHY FOG LOCATED WITHIN THIS NARROW BAND. BOTH
THE RAP AND SREF ARE HANDLING THESE LOW CLOUDS/REDUCED VISIBILITY
WELL...AND HAVE IT DISSIPATING BY 15Z. OTHERWISE...THE REMAINDER OF
THE CWA REMAINS FOG FREE THIS MORNING SO REMOVED MOST OF THE FOG
FROM THE FORECAST. HIGH PRESSURE SITUATED ACROSS THE REGION THIS
MORNING WILL PUSH OFF TO THE EAST THROUGH THE DAY...AND AS IT DOES
SO THE LOW LEVEL FLOW WILL BECOME SOUTHEASTERLY. THIS AND A
STRENGTHENING INVERSION WILL INHIBIT MIXING TODAY...ESPECIALLY IN
THE EAST...AND IN RESPONSE HIGH TEMPERATURES WILL GENERALLY BE
COOLER THAN YESTERDAY. STILL VERY MILD FOR THIS TIME OF YEAR
HOWEVER...TOPPING OUT IN THE LOWER 40S THROUGH SOUTHWESTERN
MINNESOTA INTO THE EASTERN PORTIONS OF OUR IOWA ZONES...TO 50S
THROUGH THE JAMES RIVER VALLEY THROUGH THE LOWER MISSOURI RIVER
CORRIDOR.
A SURFACE TROUGH BEGINS TO APPROACH FROM THE WEST TONIGHT...AND IT
WILL BE A MILDER NIGHT WITH INCREASING WARM AIR ADVECTION OUT AHEAD
OF THE SYSTEM. WITH THAT...LOOKING AT LOWS GENERALLY LOWER TO MID
30S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 257 AM CST TUE JAN 27 2015
WEDNESDAY STILL TO BE THE FINAL VERY MILD DAY AS LOW PRESSURE PASSES
AND COOLER AIR BEGINS TO DRAIN SOUTHWARD. MODELS SIMILAR TO
YESTERDAY SO NO REAL CHANGES. STILL MAINTAIN A SMALL CHANCE FOR
LIGHT SNOW IN THE NORTH AS A WAVE PASSES BY BUT A BIT MOISTURE
STARVED SO NOT ANTICIPATING MUCH OF ANYTHING.
BECOMING A BIT WINDY LATE WEDNESDAY AFTERNOON AND NIGHT AS COLD AIR
ADVECTION AND A STRONG PRESSURE GRADIENT WORK TO MIX DOWN SOME
STRONG WINDS ALOFT. LIKELY SEE SOME WIND GUSTS OF 35 MPH OR SO
WEDNESDAY NIGHT. WITH SOME CLOUD COVER AND WIND TEMPERATURES SHOULD
STAY FAIRLY MILD FOR THIS TIME OF YEAR WITH THURSDAY MORNING LOWS
FROM THE MID 20S TO LOWER 30S.
THURSDAY STILL A BIT BREEZY AND DEFINITELY COLDER. THE LOWER LEVEL
THERMAL FIELD HAS COME IN A BIT COLDER THIS TIME AROUND WHICH IS
ALSO FAIRLY WELL AGREED UPON SO WENT AHEAD AND LOWERED HIGHS A
COUPLE OF DEGREES. HIGHS MAINLY UPPER 20S TO MID 30S.
IN THE OUTER PERIODS (FRIDAY THROUGH MONDAY)...THE COLDER PATTERN
SETTLES IN AND REMAINS IN PLACE. MODELS ALL IN PRETTY GOOD AGREEMENT
THIS TIME AROUND SO WILL KEEP TEMPERATURES ON THE COLDER SIDE OF
GUIDANCE. FRIDAY IS THE LAST OF THE MILD DAYS AS SOUTHERLY FLOW
KEEPS 925MB TEMPERATURES CLOSER TO ZERO. SATURDAY LIKELY POSING THE
POTENTIAL FOR THE BIGGEST ERROR IN FORECASTING AS THE ARCTIC
BOUNDARY IS PROGGED TO MOVE THROUGH. A LITTLE FASTER AND HIGHS WILL
BE IN THE 20S...A LITTLE SLOWER AND HIGH WOULD BE IN THE 40S SO
UPPER 20S IN THE NORTH AND MID 30S IN THE SOUTH SEEMS LIKE A GOOD
HEDGE TOWARDS THIS FAIRLY SHARP THERMAL GRADIENT. WILL ALSO HAVE A
CHANCE FOR LIGHT SNOW ON SATURDAY AND SATURDAY NIGHT AS THIS COLD
AIR SURGES SOUTH. SUNDAY AND MONDAY WELL INTO THE COLD AIR SO JUST
LOOKING AT HIGHS IN THE TEENS TO LOWER 20S AND LOWS IN THE SINGLE
DIGITS TO LOWER TEENS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1040 AM CST TUE JAN 27 2015
HAVE AMENDED TAFS AT KFSD THIS MORNING TO KEEP LOW CLOUDS AND FOG
THROUGH EARLY AFTERNOON. ELSEWHERE...INCREASING SOUTHEASTERLY
WINDS ARE EXPECTED TODAY INTO TONIGHT. QUESTIONS REMAIN HOW LONG
STRATUS WILL HANG TOUGH...ESPECIALLY ACROSS SOUTHWEST MINNESOTA.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...DENSE FOG ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR SDZ040-056-
062-067.
MN...DENSE FOG ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR MNZ071-072-
080-089-097-098.
IA...DENSE FOG ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR IAZ001-002-
012-013.
NE...NONE.
&&
$$
UPDATE...
SHORT TERM...JM
LONG TERM...08
AVIATION...
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 258 PM CST TUE JAN 27 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH
PRESSURE NOSING SOUTHWEST ACROSS THE UPPER PENINSULA AND THE STATE
OF WISCONSIN. BUT DESPITE THE RIDGE AXIS SHARPENING OVER NE
WISCONSIN...LOW STRATUS HAS BEEN AWFULLY DIFFICULT TO ERODE THIS
AFTERNOON. CLOUDS OVER NORTHERN LAKE MICHIGAN ARE VERY SLOWLY
ERODING FROM EAST TO WEST...AND AS BOUNDARY LAYER FLOW LIGHTENS AND
BACKS TO THE NORTH LATER THIS AFTERNOON...THINK THIS WILL ACCELERATE
CLEARING OVER THE FOX VALLEY AND LAKESHORE. OTHERWISE...OVERCAST
CONDITIONS TO REMAIN OVER CENTRAL AND NORTH-CENTRAL WISCONSIN.
LOOKING UPSTREAM...CLOUDS ARE INCREASING AGAIN OVER THE NORTHERN
PLAINS AND NORTHWEST LAKE SUPERIOR AHEAD OF THE NEXT CLIPPER SYSTEM
WHICH WILL ARRIVE WEDNESDAY NIGHT. IN THE MEANTIME...CLOUD AND TEMP
TRENDS ARE THE MAIN FORECAST CONCERNS.
TONIGHT...ARCTIC HIGH PRESSURE WILL TEMPORARILY BUILD ACROSS EASTERN
WISCONSIN THIS EVENING THEN RETREAT BACK EAST OVERNIGHT. STILL
ANTICIPATING AT LEAST PARTIAL CLEARING TAKING PLACE OVER THE FOX
VALLEY AND LAKE SHORE AS THE RIDGE AXIS MOVES INTO THAT AREA. FARTHER
WEST...WINDS WILL TURN TO THE SOUTH OR SOUTHWEST...AND TRENDS OVER
THE U.P. SUPPORT THAT CLOUDS WILL JUST ROTATE NORTHWARD...LEAVING A
LOW OVERCAST DECK IN PLACE. AS A RESULT...INCREASED SKY COVER.
THEN OVERNIGHT...MID AND HIGH CLOUDS WILL BE RETURNING FROM THE
NORTHWEST...AND ANY CLEARING OVER EASTERN WISCONSIN SHOULD GO BACK
TO BROKEN OR OVERCAST. TRENDED WARMER WITH LOW TEMPS DUE TO THE
PERSISTENT CLOUD COVER.
WEDNESDAY...LOW PRESSURE WILL BE MOVING INTO THE NORTHERN
MISSISSIPPI VALLEY DURING THE AFTERNOON. AS WINDS BACK TO THE
SOUTHEAST...WARMER LOW LEVEL AIR WILL FINALLY SURGE INTO CENTRAL AND
NORTHEAST WISCONSIN...WHICH SHOULD ERODE ANY REMAINING LOW OVERCAST.
HOWEVER...WILL STILL HAVE AMPLE MID AND UPPER CLOUDS
OVERHEAD...MAKING FOR A MOSTLY CLOUDY DAY. AN 850MB WARM FRONT WILL
BE MAKING INTO NORTH-CENTRAL AND CENTRAL WISCONSIN BY LATE IN THE
AFTERNOON...BUT PROGGED SOUNDINGS CONTINUE TO SHOW A WEDGE OF DRY
AIR AROUND 10KFT THAT SHOULD BE ENOUGH TO KEEP THE AREA DRY. HIGHS
WARMING INTO THE LOW TO MID 30S.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 258 PM CST TUE JAN 27 2015
NORTHWEST UPPER FLOW WILL CONTINUE THROUGH THE PERIOD...SO IT WILL
BE GENERALLY COLD AND DRY. THERE ARE AT LEAST TWO OPPORTUNITIES FOR
SOME SNOW. THE FIRST IS TOMORROW NIGHT AND EARLY THURSDAY AS JET
ENERGY APPROACHES FROM THE WEST. THERE ISN/T MUCH MOISTURE
AVAILABLE UNTIL THE SYSTEM GETS EAST OF WISCONSIN. THEREFORE SNOW
SHOULD BE LIGHT AND MIGHT BEGIN AS SLEET ACROSS THE CENTRAL AND
EAST CENTRAL AREAS. THERE IS ANOTHER CHANCE OF SNOW SATURDAY NIGHT
AND SUNDAY AHEAD OF ARCTIC AIR. THE GFS AND ECMWF HAVE A FEW WAVES
OF LOW PRESSURE THAT MOVE NORTHEAST ALONG THE FRONT...RESULTING IN
LOTS OF DIFFERENCES IN TIMING AND SNOW AMOUNTS. MILD PACIFIC AIR
WILL BRING US WARMER THAN NORMAL TEMPERATURES THURSDAY THEN BELOW
NORMAL TEMPERATURES ARE EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
THERE. WIND CHILL ADVISORIES MAY BE NEEDED MONDAY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1121 AM CST TUE JAN 27 2015
WIDESPREAD MVFR AND IFR CIGS CONTINUE TO IMPACT THE REGION LATE THIS
MORNING. HAVE TRENDED MORE PESSIMISTICALLY WITH THIS FORECAST
DESPITE ARCTIC HIGH PRESSURE BUILDING SOUTHWEST INTO THE STATE.
THOUGH CLEARING IS TRYING TO PUSH IN FROM THE EAST...PROGRESS HAS
BEEN SLOWER THAN ORIGINALLY THOUGHT AND NOW THINK THAT THE CENTRAL
AND NORTH-CENTRAL TAFS SITES WILL REMAIN MVFR OVERCAST DURING THE
AFTERNOON AND PART OF THE EVENING. ANTICIPATED CIGS LOWERING AGAIN
OVERNIGHT IN THIS AREA AS THE INVERSION LOWERS. ACROSS EASTERN
WISCONSIN...POTENTIAL REMAINS FOR CLEARING TO TAKE PLACE LATER THIS
AFTERNOON WHEN WINDS OFF THE LAKE SUBSIDE. NO MATTER WHAT THE LOW
CLOUDS DO...MID AND HIGH CLOUDS WILL BE INCREASING TONIGHT THOUGH
EXPECT PRECIP TO HOLD OFF UNTIL LATER PERIODS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC