Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/11/13


AREA FORECAST DISCUSSION
NWS TAUNTON MA
632 PM EST SUN NOV 10 2013 .SYNOPSIS... A COLD FRONT WILL MOVE OFFSHORE TONIGHT FOLLOWED BY BLUSTERY CONDITIONS. A WEAK RIDGE OF HIGH PRESSURE BUILDS IN MONDAY...THEN AN ARCTIC FRONT WILL MOVE ACROSS THE REGION LATE TONIGHT AND EARLY TUE ACCOMPANIED BY SCATTERED RAIN AND SNOW SQUALLS. MUCH COLDER AIR SETTLES OVER THE AREA TUESDAY AND WEDNESDAY...BUT THEN MODERATING TEMPERATURES ARE EXPECTED TOWARD THE END OF THE WEEK INTO NEXT WEEKEND. && .NEAR TERM /THROUGH MONDAY/... POTENT DISTURBANCE MOVING OFFSHORE. THE COMBINATION OF REAR-WARD SUBSIDENCE AND STRENGTHENING WEST-NORTHWEST FLOW RESULTING IN CLOUD BREAKS AND COLD AIR ADVECTION THROUGH THE LOW-LEVELS. A FEW POINTS TOWARDS THE FORECAST...SPC MESOANALYIS SHOWS STEEP LOW-LEVEL LAPSE RATES OF AROUND 7 C/KM GRADUALLY PUSHING EAST BEHIND THE AFOREMENTIONED DISTURBANCE. RAP H925-85 FLOW IS MODELED 25-35 KTS PRESENTLY...WITH 35-45 KTS UPSTREAM ACROSS NY/PA. RADAR VERTICAL WIND PROFILERS CONCUR. WATER TEMPERATURES REMAIN MILD WITH VALUES AROUND THE MID- 50S AIDING TO KEEP CONDITIONS WARMER FOR THE SHORES. CONSIDERING SUCH POINTS...THE EVENING LOOKS TO BE BLUSTERY...MORE SO ALONG THE NEAR-SHORE AND ADJACENT WATERS. FREQUENT GUSTS OF AROUND 20 TO 25 MPH ARE EXPECTED ACROSS THE INTERIOR...WHILE GUSTS OF AROUND 35 MPH WILL IMPACT THE SHORES. A COLDER AIRMASS DIGGING IN WILL RESULT IN LOWS DOWN TO THE LOW- TO MID-30S WITH 20S ACROSS THE HIGHER TERRAIN. && .SHORT TERM /MONDAY NIGHT/... MONDAY... SFC RIDGE AXIS QUICKLY MOVES ACROSS THE REGION DURING THE MORNING THEN OFFSHORE. STILL A TAD BREEZY IN THE MORNING...THEN DIMINISHING WIND DURING THE AFTERNOON. SUNSHINE IN THE MORNING WILL GIVE WAY TO INCREASING CLOUDS IN THE AFTERNOON FROM WEST TO EAST AS THE ARCTIC FRONT APPROACHES. HOWEVER ANY PRECIP WILL HOLD OFF UNTIL LATER MON NIGHT. MAX TEMPS MOSTLY IN THE 40S...TO NEAR 50 IN THE COASTAL PLAIN. MONDAY NIGHT... MODELS ARE SIMILAR WITH TIMING OF THE ARCTIC FRONT AFTER MIDNIGHT IN THE WEST AND CLEARING THE COAST BY DAYBREAK. DEEP MOISTURE AXIS MOVES IN ALONG AND AHEAD OF THE FRONT AND GUIDANCE INDICATING GOOD FORCING WITH LOW LEVEL FRONTOGENESIS AND RIGHT ENTRANCE REGION OF A 130 KT UPPER LEVEL JET. THIS STRONGLY SUPPORTS A BAND OF RAIN/SNOW SHOWERS MOVING THROUGH SNE...AND COULD EVEN SEE SOME BRIEF HEAVIER SQUALLS PER AREA OF -EPV COLOCATED WITH THE FGEN BAND. FOR PTYPE...PRECIP SHOULD BEGIN AS RAIN THEN CHANGE TO SNOW AS COLDER AIR DEEPENS. ALONG THE COAST THE SHOWERS WILL CHANGE TO A BRIEF PERIOD OF SNOW SHOWERS LATE MON NIGHT INTO EARLY TUE BEFORE ENDING. MINOR ACCUM LESS THAN 1" POSSIBLE OVER THE HIGHER ELEVATIONS. && .LONG TERM /TUESDAY THROUGH SUNDAY/... HEADLINES... * RAIN/SNOW SQUALLS POSSIBLE TUESDAY MORNING * BLUSTERY NORTHWEST WINDS INTO MIDWEEK * HIGH PRESSURE FOR THE LATE-WEEK INTO EARLY WEEKEND * A RETURN TO MORE ACTIVE WEATHER POSSIBLE BY NEXT WEEK */OVERVIEW AND MODEL CONSENSUS... WHILE TRENDS ARE APPARENT...THE LARGE DEGREE OF ENSEMBLE SPREAD WITHIN FORECASTED ATMOSPHERIC TELECONNECTIONS LENDS TO BROAD-SCALE UNCERTAINTY AS TO OUTCOMES NEXT WEEK INTO THE FOLLOWING WEEKEND. THIS IS LIKELY THE CONSEQUENCE AS TO HOW POLAR LOWS ARE INDIVIDUALLY HANDLED AS WELL AS THEIR INTERACTION WITH PACIFIC DISTURBANCES THROUGH THE MARITIME FLOW. ENSEMBLE MEAN SOLUTIONS ARE MUCH LESS AMPLIFIED THAN THEIR DETERMINISTIC COUNTERPARTS. IF THE NAO/AO INDICES SHIFT NEGATIVE AS SUGGESTED...THEN LIKELY INTO THE LATER HALF OF NOVEMBER AN ACTIVE PATTERN WOULD BE EXPECTED ALONG WITH MORE SUBSTANTIAL TEMPERATURE VARIATIONS CLOSER TO RECORD EXTREMES. THOUGH DIFFERENCES IN OUTCOMES DO EXIST...TRENDS WITHIN THE H5 PATTERN ARE COHESIVE AMONG DETERMINISTIC SOLUTIONS ALLOWING FOR A COMPREHENSIVE BLEND. 10.12Z GFS/NAM AND 10.0Z GEFS MEAN CONTINUE TO BE SLIGHTLY FASTER THAN THE 10.12Z CANADIAN AND 10.0Z ECMWF WITH REGARDS TO THE ARCTIC COLD FRONT PUSHING OFFSHORE. +NAO/+AO DO SUGGEST A MORE PROGRESSIVE PATTERN DOWNSTREAM. GOOD AGREEMENT OF CANADIAN HIGH PRESSURE LINGERING INTO THE END OF THE WEEK...BUT POOR HANDLING OF AN UPSTREAM HUDSON BAY CLIPPER LOW AND ATTENDANT COLD FRONT THROUGH THE CENTRAL CONUS. THIS IS ABOUT THE POINT /FRIDAY/ WHEN SURFACE OUTCOME SPREAD GREATLY INCREASES LENDING TO OVERALL FORECAST UNCERTAINTY. WILL HIT UPON THE KEY THREATS AND IMPACTS WITHIN THE DAILIES BELOW. */DAY-TO-DAY DETAILS... */TUESDAY INTO TUESDAY NIGHT... ARCTIC COLD FRONT PUSHING OFFSHORE WITH ANAFRONT CHARACTERISTICS. BROAD-SCALE LIFT TO THE REAR OF AVAILABLE MOISTURE WILL YIELD LINGERING RAIN/SNOW SHOWERS FOR THE MORNING PERIOD. SQUALLS POSSIBLE WITH AN UNSTABLE BOUNDARY LATER. MINOR ACCUMULATION. COULD BE SOME VISIBILITY ISSUES WITH STRONGER SQUALLS DURING THE MORNING COMMUTE. FEEL THE PRESSURE GRADIENT WILL MAINTAIN AND TIGHTEN TO THE REAR OF THE DEPARTING SYSTEM. WITH STEEP LOW-LEVEL LAPSE RATES ALLOWING THE MIX-DOWN OF FASTER MOMENTUM TO THE SURFACE...WEST-NORTHWEST WIND GUSTS OF 25 TO 30 MPH NOT OUT OF THE QUESTION...DIMINISHING OVERNIGHT EXCEPT ALONG THE NEAR-SHORE AND ADJACENT WATERS. COLD AIR ADVECTION PROCEEDING...COLDEST NIGHT OF THE SEASON ON TAP. HIGHS AROUND THE UPPER-30S TO LOW-40S. LOWS AROUND THE LOW- TO MID- 20S. COLDER ACROSS HIGHER TERRAIN WITH TEENS. EFFECTIVE RADIATIONAL COOLING CERTAINLY PLAUSIBLE IN THE NORTHERN AND WESTERN INTERIOR... ESPECIALLY IN SHELTERED VALLEYS. */WEDNESDAY INTO WEDNESDAY NIGHT... ANOTHER DAY OF A WELL-MIXED BOUNDARY LAYER WILL YIELD NORTHWESTERLY WIND GUSTS AT THE SURFACE AROUND 15 MPH...SLIGHTLY STRONGER SOUTH AND EAST OVER THE WATERS. WINDS TAPER INTO THE EVENING BECOMING LIGHT AND VARIABLE OVERNIGHT. COLDEST AIR ACROSS THE REGION AROUND 0Z THURSDAY...WARM AIR ADVECTION PROCEEDING THEREAFTER. MAY LIMIT EFFECTIVE RADIATIONAL COOLING. STILL LOOKING AT OVERNIGHT LOWS OF THE LOW- TO MID-20S WITH TEENS ACROSS THE HIGHER TERRAIN AS HIGHS EARLIER IN THE DAY ONLY RISE INTO THE MID- TO UPPER-30S. */THURSDAY INTO SATURDAY... RETURN SOUTHERLY FLOW AND A MODERATING TEMPERATURE TREND GRADUALLY RISING SLIGHTLY ABOVE SEASONAL CONDITIONS. BOUNDARY LAYER MIXING WILL BE LIMITED UNDERNEATH A SUBSIDENCE INVERSION...BUT AN OCCASIONAL WEST-SOUTHWESTERLY WIND GUST OF 10 TO 15 MPH IS POSSIBLE. MOSTLY CLEAR CONDITIONS. */SUNDAY INTO NEXT WEEK... HIGH PRESSURE SHIFTING NORTH AND EAST. WINDS VEERING EAST- SOUTHEASTERLY IN RESPONSE TO AN APPROACHING SYSTEM. ACTIVE WEATHER POSSIBLE BY THE MIDWEEK PERIOD. && .AVIATION /23Z SUNDAY THROUGH FRIDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH MONDAY NIGHT/...HIGH CONFIDENCE. VFR. SCT-BKN 050 CIGS MAINLY WEST. W/NW WIND GUSTS AROUND 20-25 KTS OVER THE INTERIOR...WITH GUSTS AROUND 30 KTS ALONG THE SHORES. WHILE ACTIVITY DIMINISHES MONDAY AS WINDS VEER SOUTH-SOUTHWESTERLY EXPECT THE RETURN OF BLUSTERY CONDITIONS PRIOR TO A COLD FRONT SWEEPING THE TERMINALS MONDAY NIGHT. SCATTERED -SHRA/-SHSN WHICH COULD POSE MVFR/IFR IMPACTS IN BOTH CIGS AND VSBYS. KBOS TAF...HIGH CONFIDENCE IN TAF. KBDL TAF...HIGH CONFIDENCE IN TAF. OUTLOOK...TUESDAY THROUGH FRIDAY... */TUESDAY INTO TUESDAY NIGHT... VFR. -SHRA/-SHSN FOR THE MORNING WITH LOW-END VFR CIGS /MVFR OVER THE FAR SOUTH AND EAST/. CLEARING THEREAFTER. BLUSTERY NORTHWESTERLY WINDS AROUND 25 KTS /30 KTS SOUTH AND EAST/ TAPERING INTO EVENING EXCEPT ALONG THE NEAR-SHORE TERMINALS. */WEDNESDAY INTO WEDNESDAY NIGHT... VFR. NORTHWEST WINDS CONTINUING TO TAPER TO LIGHT AND VARIABLE OVERNIGHT. */THURSDAY INTO FRIDAY... VFR. WINDS BACKING SOUTHERLY WITH GUSTS UP TO AROUND 10 TO 15 KTS POSSIBLE. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH MONDAY NIGHT/...HIGH CONFIDENCE. GALE WARNINGS WILL CONTINUE ACROSS MOST OF THE WATERS TONIGHT FOR G35-40 KT. WE DOWNGRADED TO A STRONG SCA WITH G30 KT FOR BOS HARBOR AND NARRAGANSETT MAY. WINDS DIMINISH AND BECOME SW DURING TUE...BUT ANOTHER PULSE OF GUSTY WINDS TO 30 KT LIKELY MON NIGHT...INITIALLY SW AHEAD OF THE FRONT THEN SHIFTING TO NW LATE MON NIGHT. LOW PROB OF NEAR GALES. SCT SHOWERS EXPECTED LATE MON NIGHT. OUTLOOK...TUESDAY THROUGH FRIDAY... */TUESDAY INTO TUESDAY NIGHT... COLD FRONT SWEEPS THE WATERS WITH LINGERING RAIN SHOWERS TO THE REAR. THEREAFTER BLUSTERY NORTHWEST WINDS WITH GUSTS UP TO AROUND 30 KTS SLOWLY TAPERING INTO THE EVENING. SEAS BECOMING MORE CHOPPY. SMALL CRAFT ADVISORIES...LOW CONFIDENCE GALE HEADLINES. */WEDNESDAY INTO WEDNESDAY NIGHT... NORTHWEST WINDS TAPERING WITH GUSTS AROUND 20 KTS. SEAS TO SLOWLY DEAMPLIFY. EXPECTING A CONTINUATION OF SMALL CRAFT ADVISORIES MAINLY FOR SEAS. */THURSDAY INTO FRIDAY... WINDS TURNING SOUTHERLY. GUSTS AROUND 10 TO 15 KTS POSSIBLE. OTHERWISE WINDS AND SEAS BELOW SMALL CRAFT ADVISORY THRESHOLDS. && .CLIMATE... RECORD LOW TEMPERATURES FOR NOVEMBER 13TH - 14TH... BOSTON... 14 /1883/ - 16 /1905/ HARTFORD... 18 /2001/ - 15 /1986/ PROVIDENCE...20 /2001/ - 16 /1905/ WORCESTER... 15 /1986/ - 10 /1986/ && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...GALE WARNING UNTIL 7 AM EST MONDAY FOR ANZ231>234-250-251-254. SMALL CRAFT ADVISORY UNTIL 10 AM EST MONDAY FOR ANZ230-236. GALE WARNING UNTIL 7 AM EST MONDAY FOR ANZ235-237-255-256. && $$ SYNOPSIS...KJC/SIPPRELL NEAR TERM...KJC/SIPPRELL SHORT TERM...KJC LONG TERM...SIPPRELL AVIATION...KJC/SIPPRELL MARINE...KJC/SIPPRELL CLIMATE...SIPPRELL
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1003 PM EST SUN NOV 10 2013 .SYNOPSIS... DRY HIGH PRESSURE WILL DOMINATE THROUGH MONDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE TUESDAY OR EARLY WEDNESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... A DRY COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TONIGHT. INCREASED MIXING ASSOCIATED WITH RELATIVELY WARM WATER TEMPERATURES WILL RESULT IN BREEZY CONDITIONS BEHIND THE FRONT ON AREA LAKES. THE HRRR INDICATES LAKE WIND ADVISORY CRITERIA ON LAKE MARION. THE PRESSURE GRADIENT APPEARS A LITTLE LESS FARTHER WEST. SATELLITE TRENDS SUPPORT MOSTLY CLEAR SKIES. MIXING SHOULD HELP HOLD UP TEMPERATURES. WE LEANED TOWARD THE WARMER TEMPERATURE GUIDANCE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... DRY HIGH PRESSURE DOMINATES THROUGH MONDAY. MODELS IN GOOD AGREEMENT WITH PATTERN CHANGE TUESDAY AS HIGHLY AMPLIFIED POSITIVELY TILTED UPPER-LEVEL TROUGH DEVELOPS IN THE EASTERN STATES...RIDGE OUT WEST. THIS TROUGH WILL TRANSPORT VERY COLD AIR FOR THIS TIME OF YEAR INTO THE SOUTHEAST...ARCTIC AIR MASS ORIGIN. LATEST MODELS RUN SUGGEST MORE CLOUDINESS BY EARLY AFTERNOON AS FRONT APPROACHES SO CUT TEMPERATURES FROM PREVIOUS FORECAST AND INCREASED WINDS BEHIND THE FRONT AS STRONG COLD ADVECTION DEVELOPS. THE FRONT SHOULD PUSH THROUGH THE AREA BY LATE TUESDAY. THE COLDEST AIR OF THE SEASON WILL SPREAD ACROSS THE REGION TUESDAY NIGHT. PRECIPITATION MAY MOVE THROUGH THE AREA...ALTHOUGH QPF EXPECTED TO BE QUITE LOW. MODELS APPEAR TO BE COMING MORE INTO ALIGNMENT WITH THE UPCOMING WEATHER EVENT. MODELS ARE TRENDING LESS AGGRESSIVE IN BRINGING IN ANY SORT OF BRIEF WINTRY MIX THAN PREVIOUS RUNS. IN FACT...LATEST GFS AND NAM KEEP PRECIPITATION ALL LIQUID FOR LATE TUESDAY NIGHT. NAM AND GFS BUFKIT INDICATING RELATIVELY SHALLOW MOISTURE WELL BELOW THE SNOW GROWTH ZONE. BEST SYNOPTIC LIFT WILL BE MAINLY OVER THE NC MOUNTAINS. POPS AND QPFS REMAIN LOW. OVERNIGHT LOWS SHOULD DIP INTO THE LOWER TO MIDDLE 30S EARLY WEDNESDAY MORNING...BUT THE BULK OF THE MOISTURE WILL HAVE MOVED EAST OF THE AREA BY THE TIME THE COLDEST TEMPERATURES ARRIVE AROUND SUNRISE WEDNESDAY. HIGHS WEDNESDAY WILL RANGE FROM THE MID 40S NORTH TO THE LOWER 50S SOUTH. WITH A DEVELOPING TIGHT PRESSURE GRADIENT...IT WILL BECOME RATHER BREEZY TUESDAY NIGHT INTO WEDNESDAY WITH SUSTAINED WIND SPEEDS OF 15 TO 25 MPH FROM THE NORTH AND NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WINDS WILL SUBSIDE BY LATE WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. HIGH PRESSURE EXPECTED TO CONTINUE INTO FRIDAY. THE GFS AND ECMWF SHOW A DEVELOPING WARM FRONT WITH WEAK ISENTROPIC LIFT SUPPORTING LOW CHANCE POPS SATURDAY AND SUNDAY. TEMPERATURES BELOW NORMAL THROUGH FRIDAY...MUCH BELOW WEDNESDAY AND THURSDAY. TEMPERATURES WILL MODERATE SATURDAY AND SUNDAY AHEAD OF THE NEXT FRONTAL SYSTEM. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE 24-HOUR TAF PERIOD. A DRY FRONT WILL MOVE ACROSS THE AREA TONIGHT. DRIER AIR ALONG WITH A LOW LEVEL 30 KT JET WILL LIMIT ANY CHANCE OF FOG FORMATION. THE LOW LEVEL JET LATER TONIGHT THEN DECREASING MONDAY MORNING WILL KEEP THE WINDS UP AFTER MIDNIGHT THROUGH LATE MONDAY MORNING. EXTENDED AVIATION OUTLOOK...DRY WEATHER FORECAST INTO TUESDAY. A COLD FRONT AND UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO EARLY WEDNESDAY...PROVIDING A SLIGHT CHANCE OF LIGHT PRECIPITATION...AND ASSOCIATED RESTRICTIONS. BREEZY CONDITIONS WILL BE POSSIBLE AS WELL TUE NT/WED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...LAKE WIND ADVISORY UNTIL 11 AM EST MONDAY FOR SCZ031-036>038. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
816 PM EST SUN NOV 10 2013 .SYNOPSIS... DRY HIGH PRESSURE WILL DOMINATE THROUGH MONDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE TUESDAY OR EARLY WEDNESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... A DRY COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TONIGHT. INCREASED MIXING ASSOCIATED WITH RELATIVELY WARM WATER TEMPERATURES WILL RESULT IN BREEZY CONDITIONS BEHIND THE FRONT ON ON AREA LAKES. THE HRRR INDICATES LAKE WIND ADVISORY CRITERIA ON LAKE MARION. THE PRESSURE GRADIENT APPEARS A LITTLE LESS FARTHER WEST. SATELLITE TRENDS SUPPORT MOSTLY CLEAR SKIES. MIXING SHOULD HELP HOLD UP TEMPERATURES. WE LEANED TOWARD THE WARMER TEMPERATURE GUIDANCE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... DRY HIGH PRESSURE DOMINATES THROUGH MONDAY. MODELS IN GOOD AGREEMENT WITH PATTERN CHANGE TUESDAY AS HIGHLY AMPLIFIED POSITIVELY TILTED UPPER-LEVEL TROUGH DEVELOPS IN THE EASTERN STATES...RIDGE OUT WEST. THIS TROUGH WILL TRANSPORT VERY COLD AIR FOR THIS TIME OF YEAR INTO THE SOUTHEAST...ARCTIC AIR MASS ORIGIN. LATEST MODELS RUN SUGGEST MORE CLOUDINESS BY EARLY AFTERNOON AS FRONT APPROACHES SO CUT TEMPERATURES FROM PREVIOUS FORECAST AND INCREASED WINDS BEHIND THE FRONT AS STRONG COLD ADVECTION DEVELOPS. THE FRONT SHOULD PUSH THROUGH THE AREA BY LATE TUESDAY. THE COLDEST AIR OF THE SEASON WILL SPREAD ACROSS THE REGION TUESDAY NIGHT. PRECIPITATION MAY MOVE THROUGH THE AREA...ALTHOUGH QPF EXPECTED TO BE QUITE LOW. MODELS APPEAR TO BE COMING MORE INTO ALIGNMENT WITH THE UPCOMING WEATHER EVENT. MODELS ARE TRENDING LESS AGGRESSIVE IN BRINGING IN ANY SORT OF BRIEF WINTRY MIX THAN PREVIOUS RUNS. IN FACT...LATEST GFS AND NAM KEEP PRECIPITATION ALL LIQUID FOR LATE TUESDAY NIGHT. NAM AND GFS BUFKIT INDICATING RELATIVELY SHALLOW MOISTURE WELL BELOW THE SNOW GROWTH ZONE. BEST SYNOPTIC LIFT WILL BE MAINLY OVER THE NC MOUNTAINS. POPS AND QPFS REMAIN LOW. OVERNIGHT LOWS SHOULD DIP INTO THE LOWER TO MIDDLE 30S EARLY WEDNESDAY MORNING...BUT THE BULK OF THE MOISTURE WILL HAVE MOVED EAST OF THE AREA BY THE TIME THE COLDEST TEMPERATURES ARRIVE AROUND SUNRISE WEDNESDAY. HIGHS WEDNESDAY WILL RANGE FROM THE MID 40S NORTH TO THE LOWER 50S SOUTH. WITH A DEVELOPING TIGHT PRESSURE GRADIENT...IT WILL BECOME RATHER BREEZY TUESDAY NIGHT INTO WEDNESDAY WITH SUSTAINED WIND SPEEDS OF 15 TO 25 MPH FROM THE NORTH AND NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WINDS WILL SUBSIDE BY LATE WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. HIGH PRESSURE EXPECTED TO CONTINUE INTO FRIDAY. THE GFS AND ECMWF SHOW A DEVELOPING WARM FRONT WITH WEAK ISENTROPIC LIFT SUPPORTING LOW CHANCE POPS SATURDAY AND SUNDAY. TEMPERATURES BELOW NORMAL THROUGH FRIDAY...MUCH BELOW WEDNESDAY AND THURSDAY. TEMPERATURES WILL MODERATE SATURDAY AND SUNDAY AHEAD OF THE NEXT FRONTAL SYSTEM. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE 24-HOUR TAF PERIOD. A DRY FRONT WILL MOVE ACROSS THE AREA TONIGHT. DRIER AIR ALONG WITH A LOW LEVEL 30 KT JET WILL LIMIT ANY CHANCE OF FOG FORMATION. THE LOW LEVEL JET LATER TONIGHT THEN DECREASING MONDAY MORNING WILL KEEP THE WINDS UP AFTER MIDNIGHT THROUGH LATE MONDAY MORNING. EXTENDED AVIATION OUTLOOK...DRY WEATHER FORECAST INTO TUESDAY. A COLD FRONT AND UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO EARLY WEDNESDAY...PROVIDING A SLIGHT CHANCE OF LIGHT PRECIPITATION...AND ASSOCIATED RESTRICTIONS. BREEZY CONDITIONS WILL BE POSSIBLE AS WELL TUE NT/WED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...LAKE WIND ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST MONDAY FOR SCZ031-036>038. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
637 PM EST SUN NOV 10 2013 .SYNOPSIS... DRY HIGH PRESSURE WILL DOMINATE THROUGH MONDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE TUESDAY OR EARLY WEDNESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... A DRY COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TONIGHT. INCREASED MIXING ASSOCIATED WITH RELATIVELY WARM WATER TEMPERATURES WILL RESULT IN BREEZY CONDITIONS BEHIND THE FRONT ON ON AREA LAKES. THE HRRR INDICATES LAKE WIND ADVISORY CRITERIA ON LAKE MARION. THE PRESSURE GRADIENT APPEARS A LITTLE LESS FARTHER WEST. SATELLITE TRENDS SUPPORT MOSTLY CLEAR SKIES. MIXING SHOULD HELP HOLD UP TEMPERATURES. WE LEANED TOWARD THE WARMER TEMPERATURE GUIDANCE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... DRY HIGH PRESSURE DOMINATES THROUGH MONDAY. MODELS IN GOOD AGREEMENT WITH PATTERN CHANGE TUESDAY AS HIGHLY AMPLIFIED POSITIVELY TILTED UPPER-LEVEL TROUGH DEVELOPS IN THE EASTERN STATES...RIDGE OUT WEST. THIS TROUGH WILL TRANSPORT VERY COLD AIR FOR THIS TIME OF YEAR INTO THE SOUTHEAST...ARCTIC AIR MASS ORIGIN. LATEST MODELS RUN SUGGEST MORE CLOUDINESS BY EARLY AFTERNOON AS FRONT APPROACHES SO CUT TEMPERATURES FROM PREVIOUS FORECAST AND INCREASED WINDS BEHIND THE FRONT AS STRONG COLD ADVECTION DEVELOPS. THE FRONT SHOULD PUSH THROUGH THE AREA BY LATE TUESDAY. THE COLDEST AIR OF THE SEASON WILL SPREAD ACROSS THE REGION TUESDAY NIGHT. PRECIPITATION MAY MOVE THROUGH THE AREA...ALTHOUGH QPF EXPECTED TO BE QUITE LOW. MODELS APPEAR TO BE COMING MORE INTO ALIGNMENT WITH THE UPCOMING WEATHER EVENT. MODELS ARE TRENDING LESS AGGRESSIVE IN BRINGING IN ANY SORT OF BRIEF WINTRY MIX THAN PREVIOUS RUNS. IN FACT...LATEST GFS AND NAM KEEP PRECIPITATION ALL LIQUID FOR LATE TUESDAY NIGHT. NAM AND GFS BUFKIT INDICATING RELATIVELY SHALLOW MOISTURE WELL BELOW THE SNOW GROWTH ZONE. BEST SYNOPTIC LIFT WILL BE MAINLY OVER THE NC MOUNTAINS. POPS AND QPFS REMAIN LOW. OVERNIGHT LOWS SHOULD DIP INTO THE LOWER TO MIDDLE 30S EARLY WEDNESDAY MORNING...BUT THE BULK OF THE MOISTURE WILL HAVE MOVED EAST OF THE AREA BY THE TIME THE COLDEST TEMPERATURES ARRIVE AROUND SUNRISE WEDNESDAY. HIGHS WEDNESDAY WILL RANGE FROM THE MID 40S NORTH TO THE LOWER 50S SOUTH. WITH A DEVELOPING TIGHT PRESSURE GRADIENT...IT WILL BECOME RATHER BREEZY TUESDAY NIGHT INTO WEDNESDAY WITH SUSTAINED WIND SPEEDS OF 15 TO 25 MPH FROM THE NORTH AND NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WINDS WILL SUBSIDE BY LATE WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. HIGH PRESSURE EXPECTED TO CONTINUE INTO FRIDAY. THE GFS AND ECMWF SHOW A DEVELOPING WARM FRONT WITH WEAK ISENTROPIC LIFT SUPPORTING LOW CHANCE POPS SATURDAY AND SUNDAY. TEMPERATURES BELOW NORMAL THROUGH FRIDAY...MUCH BELOW WEDNESDAY AND THURSDAY. TEMPERATURES WILL MODERATE SATURDAY AND SUNDAY AHEAD OF THE NEXT FRONTAL SYSTEM. && .AVIATION /00Z MONDAY THROUGH SATURDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE 24-HOUR TAF PERIOD. SATELLITE IMAGERY SHOWS THAT THE CLOUDS OF EARLIER TODAY HAVE MOVED SOUTH AND EAST OF THE AREA. A DRY FRONT WILL MOVE ACROSS THE AREA THIS EVENING. DRIER AIR ALONG WITH A LOW LEVEL 30 KT JET WILL LIMIT ANY CHANCE OF FOG FORMATION. THE LOW LEVEL JET LATER TONIGHT THEN DECREASING MONDAY MORNING WILL KEEP THE WINDS UP AFTER MIDNIGHT THROUGH LATE MONDAY MORNING. EXTENDED AVIATION OUTLOOK...DRY WEATHER FORECAST INTO TUESDAY. A COLD FRONT AND UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO EARLY WEDNESDAY...PROVIDING A SLIGHT CHANCE OF LIGHT PRECIPITATION...AND ASSOCIATED RESTRICTIONS. BREEZY CONDITIONS WILL BE POSSIBLE AS WELL TUE NT/WED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...LAKE WIND ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST MONDAY FOR SCZ031-036>038. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
609 PM EST SUN NOV 10 2013 .SYNOPSIS... DRY HIGH PRESSURE WILL DOMINATE THROUGH MONDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE TUESDAY OR EARLY WEDNESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... A DRY COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TONIGHT. INCREASED MIXING ASSOCIATED WITH RELATIVELY WARM WATER TEMPERATURES WILL RESULT IN BREEZY CONDITIONS BEHIND THE FRONT ON ON AREA LAKES. THE HRRR INDICATES LAKE WIND ADVISORY CRITERIA ON LAKE MARION. THE PRESSURE GRADIENT APPEARS A LITTLE LESS FARTHER WEST. SATELLITE TRENDS SUPPORT MOSTLY CLEAR SKIES. MIXING SHOULD HELP HOLD UP TEMPERATURES. WE LEANED TOWARD THE WARMER TEMPERATURE GUIDANCE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... DRY HIGH PRESSURE DOMINATES THROUGH MONDAY. MODELS IN GOOD AGREEMENT WITH PATTERN CHANGE TUESDAY AS HIGHLY AMPLIFIED POSITIVELY TILTED UPPER-LEVEL TROUGH DEVELOPS IN THE EASTERN STATES...RIDGE OUT WEST. THIS TROUGH WILL TRANSPORT VERY COLD AIR FOR THIS TIME OF YEAR INTO THE SOUTHEAST...ARCTIC AIR MASS ORIGIN. LATEST MODELS RUN SUGGEST MORE CLOUDINESS BY EARLY AFTERNOON AS FRONT APPROACHES SO CUT TEMPERATURES FROM PREVIOUS FORECAST AND INCREASED WINDS BEHIND THE FRONT AS STRONG COLD ADVECTION DEVELOPS. THE FRONT SHOULD PUSH THROUGH THE AREA BY LATE TUESDAY. THE COLDEST AIR OF THE SEASON WILL SPREAD ACROSS THE REGION TUESDAY NIGHT. PRECIPITATION MAY MOVE THROUGH THE AREA...ALTHOUGH QPF EXPECTED TO BE QUITE LOW. MODELS APPEAR TO BE COMING MORE INTO ALIGNMENT WITH THE UPCOMING WEATHER EVENT. MODELS ARE TRENDING LESS AGGRESSIVE IN BRINGING IN ANY SORT OF BRIEF WINTRY MIX THAN PREVIOUS RUNS. IN FACT...LATEST GFS AND NAM KEEP PRECIPITATION ALL LIQUID FOR LATE TUESDAY NIGHT. NAM AND GFS BUFKIT INDICATING RELATIVELY SHALLOW MOISTURE WELL BELOW THE SNOW GROWTH ZONE. BEST SYNOPTIC LIFT WILL BE MAINLY OVER THE NC MOUNTAINS. POPS AND QPFS REMAIN LOW. OVERNIGHT LOWS SHOULD DIP INTO THE LOWER TO MIDDLE 30S EARLY WEDNESDAY MORNING...BUT THE BULK OF THE MOISTURE WILL HAVE MOVED EAST OF THE AREA BY THE TIME THE COLDEST TEMPERATURES ARRIVE AROUND SUNRISE WEDNESDAY. HIGHS WEDNESDAY WILL RANGE FROM THE MID 40S NORTH TO THE LOWER 50S SOUTH. WITH A DEVELOPING TIGHT PRESSURE GRADIENT...IT WILL BECOME RATHER BREEZY TUESDAY NIGHT INTO WEDNESDAY WITH SUSTAINED WIND SPEEDS OF 15 TO 25 MPH FROM THE NORTH AND NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WINDS WILL SUBSIDE BY LATE WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. HIGH PRESSURE EXPECTED TO CONTINUE INTO FRIDAY. THE GFS AND ECMWF SHOW A DEVELOPING WARM FRONT WITH WEAK ISENTROPIC LIFT SUPPORTING LOW CHANCE POPS SATURDAY AND SUNDAY. TEMPERATURES BELOW NORMAL THROUGH FRIDAY...MUCH BELOW WEDNESDAY AND THURSDAY. TEMPERATURES WILL MODERATE SATURDAY AND SUNDAY AHEAD OF THE NEXT FRONTAL SYSTEM. && .AVIATION /23Z SUNDAY THROUGH FRIDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE 24-HOUR TAF PERIOD. SATELLITE IMAGERY SHOWS EXPECTED DECREASE IN CLOUDINESS ACROSS THE REGION AS THE MAIN UPPER IMPULSE MOVES EAST OF THE AREA. A DRY FRONT WILL MOVE THROUGH THIS EVENING. DRIER AIR ALONG WITH SOME WIND IS EXPECTED TO PRECLUDE FOG FORMATION LATE TONIGHT/EARLY MONDAY MORNING. EXTENDED AVIATION OUTLOOK...DRY WEATHER FORECAST INTO TUESDAY. A COLD FRONT AND UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO EARLY WEDNESDAY...PROVIDING A SLIGHT CHANCE OF LIGHT PRECIPITATION...AND ASSOCIATED RESTRICTIONS. BREEZY CONDITIONS WILL BE POSSIBLE AS WELL TUE NT/WED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...LAKE WIND ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST MONDAY FOR SCZ031-036>038. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
548 AM CST SAT NOV 9 2013 .DISCUSSION... 338 AM CST MULTIPLE ISSUES FOR THE MORNING FORECAST UPDATE...BUT MAINLY FOCUSING ON TEMPERATURES AND PCPN TRENDS FOR EARLY NEXT WEEK. FOR THE REMAINDER OF THE EARLY MORNING HOURS AND THROUGH THE DAY TODAY...THE MAIN ISSUE WILL BE THE STRONG...GUSTY WINDS IN ADVANCE OF A WEAK COLD FRONT AND AN ASSOCIATED LOW PRESSURE SYSTEM MOVING THROUGH THE UPPER MISSISSIPPI VALLEY. THROUGH THE REMAINDER OF THE EARLY MORNING HOURS...WINDS WILL GRADUALLY SUBSIDE WHILE SHIFTING FROM SLY TO SWLY. EXPECT THAT THE GUSTS UP TO AROUND 30 MPH AT ISSUANCE TIME WILL SUBSIDE TO 15 TO 25 MPH BY DAYBREAK. AS THE FRONTAL TROUGH MOVES THROUGH THE AREA WINDS WILL THEN GRADUALLY BECOME MORE WESTERLY...BUT WILL REMAIN RATHER BRISK THROUGH THE AFTERNOON UNTIL SUNSET. OTHERWISE...THERE SHOULD BE AMPLE SUNSHINE TODAY...WITH HIGHS IN THE MIDDLE TO UPPER 50S. HIGH PRESSURE MOVING IN BEHIND THE WEAK COLD FRONT WILL KEEP SKIES MOSTLY CLEAR OVERNIGHT AND WITH WINDS DROPPING OFF AS WELL AS DRIER AIR FILTERING OVER THE REGION...EXPECT THAT TEMPS SHOULD RADIATE DOWN INTO THE LOWER 30S...WITH A FEW ISOLD SPOTS DROPPING INTO THE UPPER 20S. UNDER BROAD NWLY FLOW ALOFT AND WITH THE COOL HIGH PRESSURE MOVING RIGHT OVER THE LOCAL AREA ON SUNDAY...TEMPERATURES WILL BE A BIT LOWER WITH HIGHS IN THE MIDDLE TO UPPER 40S...THOUGH SKIES WILL BE MOSTLY CLEAR AND WINDS WILL BE LIGHT. BY MONDAY...THE FOCUS WILL BEGIN TO SHIFT TO THE IMPACTS OF A COLD FRONT DROPPING OUT OF CANADA ON THE LEADING EDGE OF AN UNSEASONABLE ARCTIC HIGH PRESSURE SYSTEM. THERE HAS BEEN SOME DISAGREEMENT AMONG THE MODEL GUIDANCE ON THE SPEED WITH WHICH THE FRONT WILL PUSH SOUTHWARD...BUT HAVE SETTLED ON A SLOWER SOLUTION AS ADVERTISED BY THE ECMWF/GEM/NAM WITH THE GFS REMAINING A FAST OUTLIER. THIS WOULD PUSH THE COLD FRONT APPROACHING THE IL/WI BORDER MONDAY MORNING AND THEN STEADILY PROGRESSING SOUTH THROUGH THE CWA. THIS WILL HAVE A STRONG IMPACT ON TEMPERATURE TRENDS THROUGH THE DAY...WITH THE NORTHERN PORTIONS OF THE CWA LIKELY SEE THE HIGH TEMPERATURE DURG THE EARLY MORNING HOURS...WHILE THE SOUTHERN PORTIONS OF THE CWA SHOULD SEE THE MAX TEMP AT AROUND NOON BEFORE DROPPING OFF AS THE STRONG COLD ADVECTION SETS UP BEHIND THE FRONT. THERE SHOULD BE SOME MOISTURE POOLING ALONG THE FRONT...SO SOME LIGHT PCPN IS POSSIBLE...STARTING OUT AS SOME LIGHT SHRA AHEAD OF THE BOUNDARY... AND THEN CHANGING OVER THE A RAIN/SNOW MIX OR SOME SNOW SHOWERS BY MONDAY EVENING. HOWEVER...EVEN WHEN THE PCPN CHANGES OVER TO ALL SNOW MONDAY EVENING...NO ACCUMULATION IS EXPECTED. THE BIGGER CONCERN WILL BE THE TEMPERATURE TREND MONDAY NIGHT INTO TUESDAY MORNING. AS THE HIGH CONTINUES TO SETTLE THROUGH THE MISSOURI VALLEY...SKIES WILL CLEAR OUT AND AN EVEN DRIER ARCTIC AIRMASS WILL SETTLE OVER THE REGION. FOR TUESDAY MORNING...EXPECT MUCH OF THE CWA TO DROP INTO THE LOWER TO MIDDLE 20S...WITH SOME OF THE LOW-LYING...SHELTERED AREAS DROPPING INTO THE TEENS. THE ONLY OTHER SIGNIFICANT CHANGE TO THE GOING FORECAST WILL BE AN ADJUSTMENT TO THE LAKE EFFECT SNOW SHOWERS EXPECTED FOR TUESDAY AS WELL AS ADJUSTING THE HIGH TEMPERATURE FOR TUESDAY. THE CENTER OF THE HIGH SHOULD TAKE A SLIGHTLY MORE WESTERLY TRACK THROUGH ERN NEBRASKA AND KANSAS...WHICH WOULD THEN BRING A MORE NWLY COMPONENT TO THE SFC WINDS OVER LAKE MICHIGAN. WHILE THERMAL PROFILES WILL STILL BE CONDUCIVE TO LAKE EFFECT SNOW SHOWERS...WITH 850MB TEMPS OF -12 TO -14C OVER THE WARM LAKE WATERS WHICH ARE STILL AROUND 50F...THE MORE NWLY FETCH WILL FORCE ANY LAKE EFFECT SNOW INTO NWRN INDIANA AND WRN MICHIGAN...WITH THE MOST LIKELY IMPACT ON THE LOCAL CWA BEING FOR PORTER COUNTY...THOUGH ALL OF FAR NWRN INDIANA COULD SEE AT LEAST SOME SNOW. THE BIGGER IMPACT WILL BE ON THE HIGH TEMPERATURES FOR TUESDAY. HAVE HAD SOME CONCERN THAT THE MODELS WERE WAY TOO WARM AND NOT HANDLING THE MAX TEMPS VERY WELL FOR TUESDAY. AND THIS IS STILL THE CASE FOR MUCH OF THE GUIDANCE. GIVEN THAT THE DAYTIME HIGH TEMPERATURES ASSOCIATED WITH THIS SYSTEM WHILE IT IS STILL OVER NRN CANADA ARE SUB-ZERO...HAVE OPTED TO TREND LOWER THAN EVEN THE COLDEST GUIDANCE BY A LITTLE AND STILL HAVE SOME CONCERN THAT MAX TEMPS FORECAST FOR TUESDAY ARE STILL TOO HIGH. BUT FOR NOW...GIVEN THE FORECAST 850MB TEMPS OF -12 TO -14C OVER THE AREA...HAVE GONE WITH HIGHS OF 33-34F SOUTH OF A LINE FROM CHICAGO TO PONTIAC...WITH 30-32F HIGHS TO THE NORTH OF THIS LINE. THERE IS STILL A CHANCE THAT MORE OF THE CWA MAY NOT SEE TEMPS RISE ABOVE THE FREEZING MARK IF THE CENTER OF THE HIGH TAKES A MORE ELY TRACK. FOR THE REMAINDER OF THE FORECAST PERIOD...FROM WEDNESDAY THROUGH FRIDAY...EXPECT THAT TEMPERATURES WILL REMAIN WELL BELOW NORMAL...WITH A VERY SLOW WARMING TREND. BY FRIDAY...HIGHS SHOULD STILL ONLY BE IN THE MIDDLE TO UPPER 40S. OVERNIGHT LOWS WILL BE DOWNRIGHT COLD FOR WEDNESDAY MORNING WITH LOWS IN THE MIDDLE TO UPPER TEENS OVER PORTIONS OF THE CWA AWAY FROM THE LAKEFRONT AND URBANIZED COOK COUNTY. BUT EVEN THE WARMER AREAS WILL STILL DROP INTO THE MIDDLE 20S. ALSO...AS THE REGION REMAINS UNDER THE INFLUENCE OF THE HIGH PRESSURE...SEE LITTLE CHANCE FOR ANY PCPN THROUGH THE REST OF THE WEEK. KREIN && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * SOUTHWEST WINDS ARND 15-19KT WITH GUSTS BETWEEN 21-25KT THRU 16Z THEN VEERING WEST TO 18-21KT AND GUSTS NEARING 28-32KT. * LOW-LEVEL WIND SHEAR AT 2KFT AGL TO 55KT FROM THE S TO SW THRU 14Z THEN WINDS ALOFT DECREASE. * WINDS CONTINUE TO VEER NORTHWEST BY LATE TONIGHT...WITH GUSTS SLOWLY DECREASING TO ARND 16-18KT. BEACHLER //DISCUSSION...UPDATED 12Z... CLOUDS CONTINUE TO PEEL OFF TO THE EAST...WITH WINDS TURNING SOUTHWESTERLY EARLY THIS MORNING. WSR-88D KLOT CONTINUES TO INDICATE WINDS ALOFT AT 2KFT AGL AROUND 50KT...HOWEVER THE TREND HAS BEEN A STEADY DECLINE IN THE FREQUENCY. WILL MAINTAIN THE MENTION OF LLVL WS FOR ANOTHER 1-2 HOURS. WITH MINIMAL CLOUD COVER THIS MORNING...ANY HEATING WILL INCREASE THE MIXING AND ALLOW THE CURRENT GUSTS BETWEEN 20-25KT TO INCREASE TO 25-30KT BY MIDDAY. SOME GUIDANCE WAS INDICATING THAT GUSTS COULD GO EVEN HIGHER BY EARLY THIS AFTN TO AROUND 30-33KT...HOWEVER AT THIS TIME FELT MORE CONFIDENT STICKING WITH GUSTS JUST UNDER 30KT. SOME HIGH CLOUDS WILL FLOAT OVERHEAD TODAY...WITH SOME LOWER CLOUDS ARND 4-5KFT AGL DEVELOPING. SOUTHWEST WINDS WILL CONTINUE TO TURN WESTERLY...THEN EVENTUALLY LATER TONIGHT WINDS WILL VEER TO NORTHWEST. WINDS WILL CONTINUE TO BE BREEZY THROUGHOUT THE DAY...THEN DECREASE SLIGHTLY BY SUNSET. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS. * HIGH CONFIDENCE IN LLVL WS ENDING BY 14Z. * MEDIUM CONFIDENCE IN PRECISE TIMING OF WINDS TURNING W TO NW. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...MAINLY VFR. MONDAY...CHC OF RAIN IN THE MORNING WITH A CHC FOR A MIX WITH OR CHANGE TO ALL SNOW INCREASING INTO THE AFTERNOON AND EVE. TUESDAY...CHC FOR MVFR. WEDNESDAY-FRIDAY...MAINLY VFR. BEACHLER && .MARINE... 226 AM CST MARINE CONCERNS/HAZARDS... SPORADIC GALES CONTINUE FOR THE OPEN WATERS...WILL CONTINUE THE GALE WARNING THIS MORNING THROUGH MID-MORNING. PERHAPS A FEW GALES TO 40 KT MAY OCCUR FOR THE OPEN WATERS EARLY THIS MORNING. GALES EARLY THIS MORNING FOR THE NEARSHORE WATERS...WILL QUICKLY DIMINISH TO 20-25KT GUSTS BY DAYBREAK. GALES BEGIN TO RAMP BACK UP ACROSS THE NORTHERN HALF OF THE LAKE THIS AFTERNOON...THEN OVERSPREAD THE CENTRAL/SOUTHERN SECTIONS OF THE OPEN WATERS TONIGHT THROUGH SUNDAY MORNING. GALES LOOK LIKELY AGAIN MONDAY AND POSSIBLY TUE/WED...SO A VERY ACTIVE PATTERN SETTING UP. STRONG AREA OF LOW PRESSURE OVER WESTERN LAKE SUPERIOR WILL CONTINUE TO PRESS EAST THIS MORNING...TO JUST NORTH OF LAKE HURON THIS EVENING. THIS LOW WILL MAINTAIN THE STRENGTH AS IT CONTINUES TO SLIDE EAST INTO QUEBEC SUNDAY MORNING. A STRONG RIDGE OF HIGH PRESSURE OVER CENTRAL CANADA WILL QUICKLY SLIDE SOUTHEAST ACROSS THE PLAINS TONIGHT...REACHING THE MID-MISSOURI VALLEY SUNDAY. BETWEEN THE DEPARTING LOW PRESSURE AND STRONG HIGH PRESSURE WILL BE A TIGHT PRESSURE GRADIENT...WHICH WILL TRANSLATE INTO NORTHTWEST GALES FOR THE OPEN WATERS OF THE LAKE TONIGHT THROUGH SUNDAY MORNING. THE GRADIENT THEN BEGINS TO WEAKEN SUN AFTERNOON...WITH A LULL IN THE GALES. HOWEVER WITH THE PATTERN REMAINING VERY PROGRESSIVE...THE HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE GREAT LAKES SUNDAY NIGHT WITH WINDS BACKING TO WEST AND THE GRADIENT BEGINNING TO TIGHTEN ACROSS THE NORTHERN HALF OF THE LAKE. AT THIS TIME IT APPEARS GALES WILL NOT RETURN UNTIL MONDAY. FOR MON/TUE A SHARP COLD FRONT WILL APPROACH THE LAKE WITH A STRONG GRADIENT DEVELOPING...ASSOCIATED WITH A POTENT AND LARGE AREA OF HIGH PRESSURE DRIVING SOUTH FROM CENTRAL CANADA INTO THE CENTRAL PLAINS. THIS WILL SETUP A LONG DURATION NORTH FETCH FOR LAKE MICHIGAN...ALONG WITH POSSIBLY A LONG DURATION OF GALES. GIVEN THE LONG DURATION OF GALES EARLY IN THE WEEK...AND NORTH FETCH...WAVES WILL LIKELY BE LARGE FOR THE SOUTNERN HALF OF THE LAKE. AT THIS TIME GUIDANCE INDICATES WAVES FOR THE SOUTHERN HALF TO BE 7 TO 10 FT...ALTHOUGH DEPENDING ON WIND DIRECTION THESE WAVES COULD BE MUCH LARGER. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM SATURDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565...3 PM SATURDAY TO 9 AM SUNDAY. GALE WARNING...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777- LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 PM SATURDAY TO 9 AM SUNDAY. SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 AM SUNDAY. SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 3 PM SUNDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 525 AM CST Sat Nov 9 2013 .DISCUSSION... ISSUED 325 AM CST Sat Nov 9 2013 Much of the Midwest between systems this morning as high pressure slides to the east and an low pushes across the great lakes. Cold front expected to pass through ILX today, bringing slightly cooler air, but dry. Fairly progressive pattern in fast flow across the CONUS today will continue through much of the forecast pd. Much more amplified flow anticipated with next big forecast issue...a low passing through southern Canada and bringing a front as well Monday/Mon night. Within the more amplified flow, the Arctic air opens up and pushes into the Midwest with much colder temperatures with that front. Models starting to dig a trof in the SW going into next weekend. Looks like a hint at a pattern change to a possible split flow and not too stable just yet in the extended. Forecast at this point remains conservative overall with very few changes. SHORT TERM...Today and tomorrow... Breezy conditions today as approaching front compressing some isobars across Central Illinois. Some warming anticipated to push temps into the upper 50s/lower 60s before the cooler air with the weak cold front this afternoon. Pretty good temp drop anticipated tonight as skies clear out under the ridge and radiational cooling is maximized. Tomorrows highs about 10 degrees below todays. Tomorrow nights lows a bit warmer, though concerned that the guidance is warming too much as the southerly component to the winds does not kick in until early morning, and the cloud cover is lacking particularly in the east. May need an adjustment, depending on the speed of the cloud cover increase ahead of the next front. LONG TERM...Monday through Friday... Next front a result of a deeper trof digging in over the region as much cooler air taps into the Arctic airmass to the north. Precip will be short lived...but persisting behind the front resulting in a switch over to a mixed precip. Models have been speeding up a bit with the progression of this particular system. 00z NAM and GFS falling in line as well, even pulling ahead of the timing of the ECMWF. Differences, however, show up with available moisture for this system...and the NAM is producing far less RH in the boundary layer until the Ohio River Valley. Tuesdays high temperatures confined to the 30s behind the front. Remainder of the 7 days dry and temperatures slowly recovering from the cold blast, albeit slowly climbing to the upper 40s/lower 50s by the end of the week. && .AVIATION... ISSUED 525 AM CST Sat Nov 9 2013 VFR conditions will continue at all TAF sites next 24hrs. Expecting skies to be clear through the period with maybe a little bit of cirrus, but not enough to mention. Only issue is winds. Low level wind shear continues this morning with 50kts at 2kft so will keep WS mentioned in the TAFs until surface winds pick up in a couple of hours. Then winds will be southwest and gusting to just under 24kts. The dry cold front will sweep through this afternoon with winds remaining gusty during the afternoon. Then at 00z, expecting winds to decrease quickly and be at 11kts or less. CMI will see the front come through and winds decrease at the same time. Then expecting clear skies and west-northwest winds during the evening and overnight at all sites. Auten && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
Area Forecast Discussion National Weather Service Lincoln IL 348 AM CST Sat Nov 9 2013 .DISCUSSION... ISSUED 325 AM CST Sat Nov 9 2013 Much of the Midwest between systems this morning as high pressure slides to the east and an low pushes across the great lakes. Cold front expected to pass through ILX today, bringing slightly cooler air, but dry. Fairly progressive pattern in fast flow across the CONUS today will continue through much of the forecast pd. Much more amplified flow anticipated with next big forecast issue...a low passing through southern Canada and bringing a front as well Monday/Mon night. Within the more amplified flow, the Arctic air opens up and pushes into the Midwest with much colder temperatures with that front. Models starting to dig a trof in the SW going into next weekend. Looks like a hint at a pattern change to a possible split flow and not too stable just yet in the extended. Forecast at this point remains conservative overall with very few changes. SHORT TERM...Today and tomorrow... Breezy conditions today as approaching front compressing some isobars across Central Illinois. Some warming anticipated to push temps into the upper 50s/lower 60s before the cooler air with the weak cold front this afternoon. Pretty good temp drop anticipated tonight as skies clear out under the ridge and radiational cooling is maximized. Tomorrows highs about 10 degrees below todays. Tomorrow nights lows a bit warmer, though concerned that the guidance is warming too much as the southerly component to the winds does not kick in until early morning, and the cloud cover is lacking particularly in the east. May need an adjustment, depending on the speed of the cloud cover increase ahead of the next front. LONG TERM...Monday through Friday... Next front a result of a deeper trof digging in over the region as much cooler air taps into the Arctic airmass to the north. Precip will be short lived...but persisting behind the front resulting in a switch over to a mixed precip. Models have been speeding up a bit with the progression of this particular system. 00z NAM and GFS falling in line as well, even pulling ahead of the timing of the ECMWF. Differences, however, show up with available moisture for this system...and the NAM is producing far less RH in the boundary layer until the Ohio River Valley. Tuesdays high temperatures confined to the 30s behind the front. Remainder of the 7 days dry and temperatures slowly recovering from the cold blast, albeit slowly climbing to the upper 40s/lower 50s by the end of the week. HJS && .AVIATION... ISSUED 1044 PM CST Fri Nov 8 2013 Strong compact vort max moving across upper Mississippi Valley tonight continues to produce gusty south winds and a strong low- level jet above the boundary layer. KILX VWP indicating 51 kts at 1300ft AGL. Latest RUC suggests LLJ may intensify a bit more before shifting east and weakening by sunrise. Will retain LLWS wording on ongoing TAFs. The combination of clouds in place and the gusty winds has prevented much of a nocturnal inversion from developing. As the night progresses, upstream observations and IR imagery suggest that some partial clearing is likely and may be sufficient enough to reduce sfc winds somewhat sooner than aloft, Will include this trend in the new set of terminals. Latest model suite is a bit drier than previous run with respect to mid-level moisture and will reduce cloud coverage forecast to SCT for Saturday and SKC Saturday evening. A weak cold front trailing the system moving across the Great lakes should produce a wind shift from SW to NW during the later part of the day with a drop off in speed during the evening. Barker && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1203 AM CST SAT NOV 9 2013 .DISCUSSION... 255 PM CST THE WEATHER PATTERN WILL BE VERY ACTIVE OVER THE NEXT SEVERAL DAYS ACROSS THE CENTRAL AND EASTERN CONUS...WITH BIG CHANGES ON THE WAY FOR EARLY NEXT WEEK. THE MAIN WEATHER CONCERNS WILL FIRST FOCUS ON THE WINDS AND TEMPERATURES TONIGHT AND SATURDAY...ASSOCIATED WITH A STORM SYSTEM TRACKING ACROSS THE UPPER GREAT LAKES. ATTENTION THEN TURNS TO EARLY NEXT WEEK...WITH A SHARP COLD PUSH AND POSSIBLY SOME SNOW SHOWERS EXPECTED TO DROP ACROSS THE AREA. WATER VAPOR IMAGERY CURRENTLY SHOWS A RATHER POTENT MID-LEVEL SHORT WAVE DISTURBANCE AND AN ASSOCIATED SURFACE LOW TRANSLATING EASTWARD ACROSS THE DAKOTAS EARLY THIS AFTERNOON. STRONG PRESSURE FALLS IN EXCESS OF 6 MB/3HR ARE REALLY KICKING UP SOUTHWESTERLY LOW LEVEL WINDS AND WAA ACROSS THE PLAINS. THE WESTERLY DOWN SLOPE COMPONENT TO THESE WINDS ACROSS THE HIGH PLAINS HAS ALLOWED TEMPERATURES AT 850 MB TO WARM AROUND +14 TO 15 C AT KLBF AND KDDC THIS MORNING PER THE 12 UTC RAOBS. THE 12 UTC RAOBS ALSO INDICATED WINDS SPEEDS UP AROUND 40KT AT 850 MB ACROSS THESE AREAS OF KANSAS AND NEBRASKA...AND AREA PROFILER AND VWP DATA INDICATE THAT THESE WINDS HAVE FURTHER INCREASED TO AROUND 50 KT THROUGH THE MORNING. AS THIS SYSTEM CONTINUES ITS EASTWARD MOVEMENT ACROSS THE UPPER MIDWEST TONIGHT...THE SURFACE WARM FRONT WILL LIFT NORTHWARD ACROSS THE AREA...AND THIS STRONGER LOW LEVEL WIND FIELD WILL SET UP RIGHT ACROSS THE AREA. THEREFORE...SOME STRONGER GUSTY SOUTHWESTERLY WINDS WILL DEVELOP TONIGHT AND ON SATURDAY...AND TEMPERATURES WILL ALSO WARM NICELY ON SATURDAY AFTER A RELATIVELY MILD NIGHT TONIGHT. GUIDANCE IS CONSISTENT IN SUGGESTING THAT 850 AND 925 MB TEMPERATURES WILL RISE TO 2-4 AND 6-8 DEGREES CELSIUS...RESPECTIVELY ACROSS THE AREA. UNDER A WELL MIXED BOUNDARY LAYER WITH GUSTY WEST-SOUTHWESTERLY WINDS IN THE WARM SECTOR OF THE SYSTEM...THIS SHOULD YIELD TEMPERATURES IN THE MID 50S NORTH AND THE LOW 60S SOUTH....AND THIS THINKING IS CONSISTENT WITH MOST STATISTICAL GUIDANCE AND THE GOING FORECAST...SO LITTLE CHANGE IS NEEDED. AS MENTIONED ABOVE...SOUTHWESTERLY WINDS WILL INCREASE TONIGHT AS STRONG PRESSURE FALLS OVERSPREAD THE UPPER GREAT LAKES REGION...IN ADVANCE OF THE SURFACE LOW. CURRENT INDICATIONS ARE THAT 20 TO 25 MPH WINDS WILL DEVELOP ACROSS THE AREA OVERNIGHT...THEN BEGIN TO VEER MORE WESTERLY THROUGH THE DAY ON SATURDAY AS THE SURFACE LOW APPROACHES SOUTHEASTERN ONTARIO. WIND GUSTS OF 30 TO 35 MPH LOOK TO BE A GOOD BET ALSO...ESPECIALLY AFTER DAYBREAK ON SATURDAY. SO ALTHOUGH IT WILL BE WARMER ON SATURDAY...IT WILL ALSO BE WINDY. THERE IS STILL A SMALL CHANCE OF SOME LIGHT SHOWERS THIS EVENING...MAINLY FAR NORTH...AS THE MID LEVEL WAVE PASSES ACROSS SOUTHERN WISCONSIN. REGIONAL RADAR IMAGERY HAS BEEN INDICATING SOME WEAK VIRGA TYPE ECHOS OUT WEST ACROSS IOWA. THIS AREA IS IN AN AREA OF GOOD ISENTROPIC ASCENT. HOWEVER...POOR LOW LEVEL MOISTURE AND HENCE HIGH CONDENSATION PRESSURE DEFICIENT ARE NOT ALLOWING FOR MUCH TO DEVELOP OUT OF THE HIGH BASED CLOUD COVER. THIS ACTIVITY SHOULD PROGRESS EASTWARD ACROSS NORTHERN ILLINOIS AND SOUTHERN WISCONSIN THIS EVENING AHEAD OF THE MID LEVEL WAVE. SOME MID AND HIGH LEVEL CLOUDS ARE A DEFINITE THIS EVENING...BUT I AM NOT EXPECTING MORE THAN A FEW SPRINKLES OR VERY LIGHT RAIN SHOWERS FROM THIS ACTIVITY THIS EVENING. COOLER WEATHER RETURNS SATURDAY NIGHT INTO SUNDAY FOLLOWING THE SYSTEMS COLD FRONTAL PASSAGE. SURFACE HIGH PRESSURE WILL BUILD ACROSS THE MID MISSISSIPPI RIVER VALLEY AND DOMINATE THE AREA FOR SUNDAY. TEMPERATURES LOOK TO BE IN THE 40S TO NEAR 50 IN SOME AREAS. THE BIG STORY FOR NEXT WEEK WILL BE THE TRANSITION TO A COLD PATTERN ACROSS THE AREA. A RATHER COMPLEX UPPER AIR PATTERN IS FORECAST TO EVOLVE ACROSS THE PACIFIC AND NORTH AMERICA BY EARLY NEXT WEEK. OVERALL...THIS PATTERN WILL FEATURE BUILDING HEIGHTS ACROSS WESTERN NORTH AMERICA...DOWNSTREAM OF AN ANONYMOUSLY STRONG RIDGE ACROSS THE NORTH CENTRAL PACIFIC...JUST WEST OF THE DATE LINE...AND A DEEP TROUGH/LOW ACROSS THE EASTERN PACIFIC. THIS PATTERN SHIFT WILL ALLOW ANOTHER TROUGH...WITH A COLD AIRMASS ORIGINATING FROM THE YUKON TERRITORIES OF NORTHWESTERN CANADA...TO DROP ACROSS THE GREAT LAKES REGION EARLY NEXT WEEK. GUIDANCE CONTINUES TO SHOW THIS STRONG PUSH OF COLD AIR DROPPING ACROSS THE AREA BEHIND A COLD FRONTAL PASSAGE ON MONDAY. THERE IS STILL SOME TIMING UNCERTAINTIES WITH THE COLD FRONTAL PASSAGE ON MONDAY...BUT CONFIDENCE IN A COLD PATTERN SETTING UP IS INCREASING FOR THE EXTENDED PERIOD OF THE FORECAST. THE PUSH A COLD AIR APPEARS TO SET UP A STRONG BAROCLINIC ZONE ALONG AND IN THE WAKE OF THE FRONTAL BOUNDARY ON MONDAY/MONDAY EVENING. THIS LOOKS TO RESULT IN SHARPLY DROPPING TEMPERATURES ON MONDAY...DEPENDING ON THE TIMING OF THE FRONTAL BOUNDARY. THE OTHER CONCERN WILL BE THE POSSIBILITIES OF A PERIOD SNOW SHOWERS FOLLOWING THE FRONTAL PASSAGE. THE STRONG BAROCLINIC ZONE...APPEARS THAT IT COULD RESULT IN THE DEVELOPMENT OF A GOOD BAND OF FRONTOGENESIS IN THE VICINITY OF THE FRONTAL ZONE AND AHEAD OF THE SOUTHWARD DIGGING UPPER TROUGH. THIS SOUTHWARD DIGGING TROUGH COULD ALSO SET UP A FAVORABLE UPPER LEVEL JET STREAK PATTERN FOR BETTER FORCING IN THE WAKE OF THE FRONTAL ZONE...WITH AN ENTRANCE REGION OF A 100+ KT UPPER JET POSSIBLY SETTING UP ACROSS NORTHERN ILLINOIS MONDAY AFTERNOON/EVENING. THEREFORE...IT APPEARS THAT THIS WILL BE AN GOOD ANAFRONT TYPE FRONTAL SYSTEM...WITH MOST THE PRECIP FALLING IN THE COLD SECTOR. AS A RESULT OF THIS...THERE IS A DECENT POSSIBILITY FOR SNOW SHOWERS TO DEVELOP IN THE WAKE OF THIS FRONTAL BOUNDARY AS THE COLD AIR SPILLS SOUTHWARD. IN ADDITION...THE POTENTIAL FOR SOME MODERATE TO FORCING FOR ASCENT FROM THE FGEN...COULD ALSO RESULT IN A SMALL WINDOW OF SOME MODERATE TO HEAVIER SNOW SHOWERS. THIS WILL HAVE TO BE MONITORED OVER THE NEXT FEW DAYS. ALTHOUGH THIS WILL NOT BE A REAL SNOW MAKER FOR US...THERE IS THE POTENTIAL FOR SOME MINOR ACCUMULATIONS IF THIS STRONGER FORCING DOES MATERIALS. A VERY STRONG SURFACE HIGH...AROUND 1045 MB...IS EXPECTED TO BUILD SOUTHWARD ACROSS THE PLAINS STATES INTO TUESDAY IN THE WAKE OF THIS FRONTAL BOUNDARY. THIS LOOKS TO SET UP A GOOD NORTHERLY FETCH DOWN LAKE MICHIGAN...AND WITH 850 MB TEMPERATURES LIKELY DIPPING TO OR EVEN COLDER THAN -10 DEGREES CELSIUS AND LAKE SURFACE TEMPERATURES AROUND 10 DEGREES CELSIUS...THIS WILL SET UP A THERMODYNAMIC PROFILE FEATURING DELTA T`S IN EXCESS OF 20 DEGREES AND EQUILIBRIUM HEIGHTS AT OR JUST ABOVE 10,000 FT AGL. THEREFORE...IT APPEARS THAT THERE COULD BE A GOOD SETUP FOR LAKE EFFECT SNOW SHOWERS FOR NORTHWESTERN INDIANA MONDAY NIGHT AND TUESDAY. SOME ACCUMULATIONS ARE POSSIBLY WITH THIS ACTIVITY...BUT IT IS WAY TO EARLY FOR AMOUNTS. FOR THE REMAINDER OF THE AREA...AWAY FROM THE LAKE EFFECT POTENTIAL...COLD WILL BE THE MAIN STORY. WITH THE 850 TEMPS PROGGED TO DROP DOWN AROUND -10...SURFACE TEMPERATURES MAY STRUGGLE TO GET MUCH ABOVE FREEZING ON TUESDAY...AND OVERNIGHT LOWS WILL EASILY DROP INTO THE LOW 20S AND TEENS AWAY FROM THE CITY. TEMPERATURES WILL TRY TO MODERATE SOME LATE IN THE WEEK SOUTHWEST FLOW SETS UP ON THE BACK SIDE OF THE SURFACE HIGH...BUT OVERALL CONDITIONS WILL REMAIN BELOW NORMAL THROUGH THE PERIOD. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * SOUTH WINDS ARND 15-19KT WITH GUSTS BETWEEN 21-25KT THRU 09Z. * LOW-LEVEL WIND SHEAR AT 2KFT AGL TO 55KT FROM THE S TO SW THRU DAYBREAK. * SOUTH WINDS VEERING SOUTHWEST WITH A BRIEF BREAK IN THE GUSTS BEFORE DAYBREAK...THEN GUSTS RETURN TO 25-30KT BY MIDDAY. BEACHLER //DISCUSSION...UPDATED 06Z... VERY TIGHT PRESSURE GRADIENT OVER NORTHERN IL/NORTHWEST IN AIRFIELDS HAS ALLOWED A STRONG CORE OF WINDS ALOFT AT 2KFT AGL TO 55-60 KTS TO DEVELOP LLVL WS OVER THE TAF SITES. GUIDANCE CONTINUES TO INDICATE THAT THIS CORE OF WINDS WILL QUICKLY PEEL OFF TO THE EAST BY 09Z. THIS WILL LIKELY RESULT IN DECOUPLED WINDS AT THE SFC AND A BRIEF PERIOD OF GUSTS AND WIND SPEEDS DECREASING ARND 09-12Z. THEN SHORTLY AFT DAYBREAK MIXING WILL RETURN AND HELP BRING SPEEDS AND GUSTS BACK BY MIDDAY SAT TO 25-30KT AS WINDS SLOWLY TURN SOUTHWEST. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS. * HIGH CONFIDENCE IN LLVL WS. * MEDIUM CONFIDENCE IN PRECISE TIMING OF WINDS TURNING SW TO W. BEACHLER //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...VFR. MONDAY...CHC OF RAIN IN THE MORNING WITH A CHC FOR A MIX WITH OR CHANGE TO ALL SNOW INCREASING INTO THE AFTERNOON AND EVE. TUESDAY...CHC FOR MVFR. WEDNESDAY-THURSDAY...VFR LIKELY. MTF && .MARINE... 316 PM CST ACTIVE WEATHER TO CONTINUE ACROSS LAKE MICHIGAN WITH STRONG SOUTHERLY WINDS EXPECTED TO DEVELOP THIS EVENING AHEAD OF A DEEPENING AREA OF LOW PRESSURE. THIS LOW CURRENTLY OVER THE NORTHERN PLAINS WILL TRANSLATE EAST ACROSS LAKE SUPERIOR BY SATURDAY AFTERNOON. MEANWHILE...SOUTH TO SOUTHWEST WINDS WILL RAMP UP TO GALES THIS EVENING. VERTICAL MIXING WILL BE INHIBITED DUE TO WARM ADVECTION...BUT SOME OF THE MOMENTUM FROM WINDS PUSHING 60 KTS AT ABOUT 2500-3000 FT WILL LIKELY BE TRANSPORTED DOWN AT TIMES...WITH A BRIEF PERIOD SURFACE GUSTS EXPECTED TO TOP OUT AROUND 40-45 KTS WITH OCCASIONAL GUSTS TO 50 KTS A POSSIBILITY. A GALE WARNING REMAINS IN EFFECT THIS EVENING AND TONIGHT...THOUGH DID PUSH BACK THE START TIME A FEW HOURS FOR THE NORTH HALF OF THE LAKE AS THE WINDS APPEAR TO BE SLIGHTLY SLOWER SPREADING NORTH ACROSS THE LAKE. A SHORT LULL IN THE GALES IS EXPECTED SATURDAY LATE MORNING AND EARLY AFTERNOON AS THE GRADIENT BECOMES A BIT BAGGY WITHIN THE FRONTAL TROUGH...BUT THE WINDS INCREASE AGAIN SATURDAY EVENING/NIGHT AS THE GRADIENT TIGHTENS AGAIN BEHIND THE FRONT AND COLD ADVECTION ALLOWS FOR DEEPER MIXING. A GALE WATCH REMAINS IN EFFECT FOR THE ENTIRE LAKE THIS PERIOD. ANOTHER LOW WILL MOVE OVER JAMES BAY MONDAY WITH A STRONG COLD FRONT PUSHING ACROSS THE GREAT LAKES. NORTHWEST GALES ARE ONCE AGAIN A POSSIBILITY BEHIND THE FRONT FROM MIDDAY MONDAY...TAPERING MONDAY NIGHT AS HIGH PRESSURE BEGINS TO BUILD OVER THE REGION. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM SATURDAY. GALE WATCH...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565...3 PM SATURDAY TO 9 AM SUNDAY. GALE WATCH...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777- LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 PM SATURDAY TO 9 AM SUNDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 AM SATURDAY. SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743...4 AM SATURDAY TO 9 AM SUNDAY. SMALL CRAFT ADVISORY...LMZ744-LMZ745...4 AM SATURDAY TO 3 PM SUNDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1102 PM CST Fri Nov 8 2013 .DISCUSSION... ISSUED 823 PM CST Fri Nov 8 2013 Increased wind gusts this evening. Otherwise forecast on track. Pressure falls are centered over Illinois this evening leading to gusty conditions continuing onto the evening. Pressure fall center has been weakening past hour or so and shifting closer to the expected track of low pressure over southeast North Dakota will continue to move rapidly east. Barker && .AVIATION... ISSUED 1044 PM CST Fri Nov 8 2013 Strong compact vort max moving across upper Mississippi Valley tonight continues to produce gusty south winds and a strong low- level jet above the boundary layer. KILX VWP indicating 51 kts at 1300ft AGL. Latest RUC suggests LLJ may intensify a bit more before shifting east and weakening by sunrise. Will retain LLWS wording on ongoing TAFs. The combination of clouds in place and the gusty winds has prevented much of a nocturnal inversion from developing. As the night progresses, upstream observations and IR imagery suggest that some partial clearing is likely and may be sufficient enough to reduce sfc winds somewhat sooner than aloft, Will include this trend in the new set of terminals. Latest model suite is a bit drier than previous run with respect to mid-level moisture and will reduce cloud coverage forecast to SCT for Saturday and SKC Saturday evening. A weak cold front trailing the system moving across the Great lakes should produce a wind shift from SW to NW during the later part of the day with a drop off in speed during the evening. Barker && .PREV DISCUSSION... ISSUED 300 PM CST Fri Nov 8 2013 The weather pattern will remain zonal with fast moving weather systems through early next week. Monday night, an Arctic trough will dig into the midwest and push our coldest air of the season into Illinois. While a period of light snow will be possible Monday night, no accumulation is expected. Below normal temps will prevail Monday night through Wed at least. SHORT TERM...Tonight through Monday night. Mid and high clouds will drift across the skies tonight, as low pressure moves from the Dakotas into the western Great Lakes. Southerly winds feeding into that system will help keep our lows warmer than last night. The warmer air will surge into the western areas first, keeping lows in the lower 40s NW of the IL river, while lows drop into the upper 30s southeast of I-70. Saturday should turn into a pleasant Fall day as highs climb into the lower 60s in many areas. A dry cold front will usher a brief airmass change for Sunday, as highs struggle to climb into the lower 50s. Monday should see some improvement in temperatures south of I-74 as the next low moves across southern Canada and an Arctic cold front approaches Illinois. The timing of arrival of that front is still a bit in question. In general, it appears the front will move through IL during the day Monday, and much colder air will arrive for Monday night. Post-frontal rain showers are expected to develop Monday afternoon. The cold air rushing into the area will work to change the precip to snow Monday evening, but dry air aloft will be working to end the precip at the same time. So any change over to snow should be brief enough to prevent any snow accumulation. Also, the ground temps should remain above freezing long enough to melt any snowfall. LONG TERM...Tuesday through Friday. Any snow showers Monday night will be east of Illinois by sunrise on Tuesday, with high temps well below normal for Tuesday afternoon. We expect highs to remain the in the 30s in most areas, which are usually highs for the 2nd week of December. Lows will likely dip into the teens north of I-72/74 Tuesday night under clear skies and light winds. A gradual warming trend will occur the remainder of the week as the Arctic high settles into the southeastern states, and southerly winds persist for a few days. It will still feel like Fall however, with highs by Friday only in the upper 40s to around 50. EJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1239 PM EST SAT NOV 9 2013 .SYNOPSIS... ISSUED AT 1227 PM EST SAT NOV 9 2013 THE FIRST OF TWO COLD FRONTS WILL MOVE THROUGH THE REGION LATE THIS AFTERNOON INTO THIS EVENING...RETURNING TEMPERATURES BACK TO NEAR OR SLIGHTLY BELOW NORMAL LEVELS. A STRONGER COLD FRONT WILL SWEEP IN MONDAY USHERING IN THE COLDEST AIR OF THE SEASON SO FAR. AFTERNOON HIGHS IN THE MIDDLE 50S TO AROUND 60 ARE EXPECTED TODAY WITH LOWS INTO THE 30S TONIGHT. BY TUESDAY AND WEDNESDAY...AFTERNOON HIGHS WILL ONLY BE IN THE 30S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 438 AM EST SAT NOV 9 2013 SQUEEZE BTWN CLIPPER SYS MOVING RAPIDLY EWD ACRS THE NRN LAKES AND STG RIDGING CNTRD OVR THE SERN US YIELDING AN INCREASINGLY BREEZY DAY GOING FWD AS FAIRLY PRONOUNCED RISE/FALL COUPLET ACRS THE UPR MIDWEST PROGRESSES EWD THROUGH THE LAKES. PEAK SFC GUSTS LOOK TO OCCUR IN 15-18Z WINDOW TIMED W/STG MOMENTUM XFER AND GEOSTROPHIC FLW W/00Z GUIDANCE AS A WHOLE LOOKING A BIT WEAK. SHRT TERM RUC PROGS WOULD INDICATE 40KT GUSTS FOR A TIME LT MORNING ACRS NW OH WITHIN RETREATING LLJ CORE AND QUITE PSBL ESP IF SIG INSOLATION DVLPS. OTRWS SHALLOW CDFNTL BNDRY TO SHIFT THROUGH CWA LT THIS AFTN/EVE W/MOD FOLLOWING CAA SURGE ESP LT TONIGHT AS LL FLW VEERS MORE SUBSTANTIALLY NWRLY. MOS ADJUSTED GUIDANCE LOOKS A BIT WARM COMPARED TO 2M PROGS AND ADJUSTED SLIGHTLY DOWNWARD FM PREV FCST...ESP SW THIRD AWAY FM ANY LK CLD INFLUENCE. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 438 AM EST SAT NOV 9 2013 A STRONG ARCTIC FRONT WILL MOVE ACROSS THE AREA LATE MONDAY/MONDAY EVENING. THE GFS CONTINUES TO BE A LITTLE FASTER WITH THE FRONT THAN THE NAM...WITH GFS GUIDANCE HIGH TEMPS MONDAY OVER 10 DEGREES COLDER THAN THE NAM OVER SOME NORTHERN LOCATIONS BEHIND THE FRONT. ALSO... THE GFS IS LESS FAVORABLE FOR LAKE EFFECT SNOW INITIALLY WITH A NORTH TO NORTH/NORTHEAST FETCH. THE SRF/ECMWF AND NAM ALL SUPPORT A MORE NORTH/NORTHWEST FETCH WITH PARCELS TRAVELLING OVER MUCH OF THE LONG AXIS OF LAKE MICHIGAN. THESE MODELS ALSO ARE FAVORABLE FOR LAKE EFFECT SNOW GIVEN THE LOCATION OF THE DENDRITIC GROWTH ZONE AND INCREASING INVERSION HEIGHTS. CONCERN FOR HEAVIER LAKE EFFECT SNOW BANDS DEVELOPING MONDAY NIGHT AS DELTA T VALUES REFLECT EXTREME INSTABILITY. OTHERWISE...LOW LEVEL WINDS WILL BACK TUESDAY NIGHT INTO WEDNESDAY...ENDING LAKE EFFECT SNOW SHOWERS. KEPT TEMPERATURES COLD TUESDAY THROUGH THURSDAY. THE ECMWF APPEARS ON TRACK WITH TEMPERATURES AND APPEARS TO HANDLE THIS SCENARIO VERY WELL. THE COLDEST TEMPERATURES SHOULD BE TUESDAY NIGHT WITH LOWS FALLING INTO THE LOWER 20S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1227 PM EST SAT NOV 9 2013 MAIN CONCERN THROUGH THE TAF PERIOD WITH BE PERIODS OF GUSTY WINDS AS OTHERWISE VFR CONDITIONS PREVAIL. SFC LOW WILL PASS BY WELL TO THE NORTH. A COLD FRONT EXTENDED FROM EASTERN WISCONSIN INTO EASTERN IOWA WITH A LARGE AREA OF STRATUS/STRATOCU IN ITS WAKE. THIS IS EXPECTED TO REMAIN NORTH OF BOTH TAF SITES...BUT COULD HAVE A BRIEF IMPACT AT KSBN GIVEN PROXIMITY TO THE CLOUD SHIELD. STRONG LL WIND FIELD AHEAD OF THE FRONT WAS BEING MIXED DOWN WITH OCCASIONAL GUSTS TO AROUND 30 KTS EXPECTED INTO THIS AFTERNOON. AS THE FRONT PASSES WINDS WILL SHIFT MORE WEST AND NORTHWEST AND DIMINISH BRIEFLY BEFORE PICKING BACK UP AGAIN THIS EVENING AND CONTINUING INTO THE OVERNIGHT HOURS. ENOUGH MIXING SHOULD TAKE PLACE TO KEEP LLWS OUT OF THE TAFS BUT WILL STILL BE A BUMPY RIDE. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST SUNDAY FOR LMZ043-046. && $$ SYNOPSIS...FISHER SHORT TERM...T LONG TERM...SKIPPER AVIATION...FISHER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
632 AM EST SAT NOV 9 2013 .SYNOPSIS... ISSUED AT 438 AM EST SAT NOV 9 2013 AN AREA OF LOW PRESSURE WILL MOVE ACROSS THE NORTHERN GREAT LAKES WITH BREEZY CONDITIONS THROUGH THIS AFTERNOON. DRY WEATHER IS EXPECTED THROUGH THE WEEKEND. HIGHS THIS AFTERNOON WILL TOP OUT IN THE MID TO UPPER 50S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 438 AM EST SAT NOV 9 2013 SQUEEZE BTWN CLIPPER SYS MOVING RAPIDLY EWD ACRS THE NRN LAKES AND STG RIDGING CNTRD OVR THE SERN US YIELDING AN INCREASINGLY BREEZY DAY GOING FWD AS FAIRLY PRONOUNCED RISE/FALL COUPLET ACRS THE UPR MIDWEST PROGRESSES EWD THROUGH THE LAKES. PEAK SFC GUSTS LOOK TO OCCUR IN 15-18Z WINDOW TIMED W/STG MOMENTUM XFER AND GEOSTROPHIC FLW W/00Z GUIDANCE AS A WHOLE LOOKING A BIT WEAK. SHRT TERM RUC PROGS WOULD INDICATE 40KT GUSTS FOR A TIME LT MORNING ACRS NW OH WITHIN RETREATING LLJ CORE AND QUITE PSBL ESP IF SIG INSOLATION DVLPS. OTRWS SHALLOW CDFNTL BNDRY TO SHIFT THROUGH CWA LT THIS AFTN/EVE W/MOD FOLLOWING CAA SURGE ESP LT TONIGHT AS LL FLW VEERS MORE SUBSTANTIALLY NWRLY. MOS ADJUSTED GUIDANCE LOOKS A BIT WARM COMPARED TO 2M PROGS AND ADJUSTED SLIGHTLY DOWNWARD FM PREV FCST...ESP SW THIRD AWAY FM ANY LK CLD INFLUENCE. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 438 AM EST SAT NOV 9 2013 A STRONG ARCTIC FRONT WILL MOVE ACROSS THE AREA LATE MONDAY/MONDAY EVENING. THE GFS CONTINUES TO BE A LITTLE FASTER WITH THE FRONT THAN THE NAM...WITH GFS GUIDANCE HIGH TEMPS MONDAY OVER 10 DEGREES COLDER THAN THE NAM OVER SOME NORTHERN LOCATIONS BEHIND THE FRONT. ALSO... THE GFS IS LESS FAVORABLE FOR LAKE EFFECT SNOW INITIALLY WITH A NORTH TO NORTH/NORTHEAST FETCH. THE SRF/ECMWF AND NAM ALL SUPPORT A MORE NORTH/NORTHWEST FETCH WITH PARCELS TRAVELLING OVER MUCH OF THE LONG AXIS OF LAKE MICHIGAN. THESE MODELS ALSO ARE FAVORABLE FOR LAKE EFFECT SNOW GIVEN THE LOCATION OF THE DENDRITIC GROWTH ZONE AND INCREASING INVERSION HEIGHTS. CONCERN FOR HEAVIER LAKE EFFECT SNOW BANDS DEVELOPING MONDAY NIGHT AS DELTA T VALUES REFLECT EXTREME INSTABILITY. OTHERWISE...LOW LEVEL WINDS WILL BACK TUESDAY NIGHT INTO WEDNESDAY...ENDING LAKE EFFECT SNOW SHOWERS. KEPT TEMPERATURES COLD TUESDAY THROUGH THURSDAY. THE ECMWF APPEARS ON TRACK WITH TEMPERATURES AND APPEARS TO HANDLE THIS SCENARIO VERY WELL. THE COLDEST TEMPERATURES SHOULD BE TUESDAY NIGHT WITH LOWS FALLING INTO THE LOWER 20S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 632 AM EST SAT NOV 9 2013 VFR FCST THIS PD. FAIRLY PRONOUNCED RISE/FALL COUPLET MIGRATING THROUGH THE WRN LAKES. PEAK GUSTS STILL XPCD IN 15-18Z TIME FRAME COINCIDENT W/MAXIMIZED MOMENTUM XFER AFT RAPID MID MORNING MIXOUT. BASED ON UPSTREAM OBS AS OF 11Z...BUMPED TAF FCST WINDS A BIT AGAIN AT KFWA AS CORE OF LLJ PERSISTS OVERHEAD. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 7 PM EST SUNDAY FOR LMZ043-046. GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LMZ043-046. && $$ SYNOPSIS...T SHORT TERM...T LONG TERM...SKIPPER AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
439 AM EST SAT NOV 9 2013 .SYNOPSIS... ISSUED AT 438 AM EST SAT NOV 9 2013 AN AREA OF LOW PRESSURE WILL MOVE ACROSS THE NORTHERN GREAT LAKES WITH BREEZY CONDITIONS THROUGH THIS AFTERNOON. DRY WEATHER IS EXPECTED THROUGH THE WEEKEND. HIGHS THIS AFTERNOON WILL TOP OUT IN THE MID TO UPPER 50S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 438 AM EST SAT NOV 9 2013 SQUEEZE BTWN CLIPPER SYS MOVING RAPIDLY EWD ACRS THE NRN LAKES AND STG RIDGING CNTRD OVR THE SERN US YIELDING AN INCREASINGLY BREEZY DAY GOING FWD AS FAIRLY PRONOUNCED RISE/FALL COUPLET ACRS THE UPR MIDWEST PROGRESSES EWD THROUGH THE LAKES. PEAK SFC GUSTS LOOK TO OCCUR IN 15-18Z WINDOW TIMED W/STG MOMENTUM XFER AND GEOSTROPHIC FLW W/00Z GUIDANCE AS A WHOLE LOOKING A BIT WEAK. SHRT TERM RUC PROGS WOULD INDICATE 40KT GUSTS FOR A TIME LT MORNING ACRS NW OH WITHIN RETREATING LLJ CORE AND QUITE PSBL ESP IF SIG INSOLATION DVLPS. OTRWS SHALLOW CDFNTL BNDRY TO SHIFT THROUGH CWA LT THIS AFTN/EVE W/MOD FOLLOWING CAA SURGE ESP LT TONIGHT AS LL FLW VEERS MORE SUBSTANTIALLY NWRLY. MOS ADJUSTED GUIDANCE LOOKS A BIT WARM COMPARED TO 2M PROGS AND ADJUSTED SLIGHTLY DOWNWARD FM PREV FCST...ESP SW THIRD AWAY FM ANY LK CLD INFLUENCE. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 438 AM EST SAT NOV 9 2013 A STRONG ARCTIC FRONT WILL MOVE ACROSS THE AREA LATE MONDAY/MONDAY EVENING. THE GFS CONTINUES TO BE A LITTLE FASTER WITH THE FRONT THAN THE NAM...WITH GFS GUIDANCE HIGH TEMPS MONDAY OVER 10 DEGREES COLDER THAN THE NAM OVER SOME NORTHERN LOCATIONS BEHIND THE FRONT. ALSO... THE GFS IS LESS FAVORABLE FOR LAKE EFFECT SNOW INITIALLY WITH A NORTH TO NORTH/NORTHEAST FETCH. THE SRF/ECMWF AND NAM ALL SUPPORT A MORE NORTH/NORTHWEST FETCH WITH PARCELS TRAVELLING OVER MUCH OF THE LONG AXIS OF LAKE MICHIGAN. THESE MODELS ALSO ARE FAVORABLE FOR LAKE EFFECT SNOW GIVEN THE LOCATION OF THE DENDRITIC GROWTH ZONE AND INCREASING INVERSION HEIGHTS. CONCERN FOR HEAVIER LAKE EFFECT SNOW BANDS DEVELOPING MONDAY NIGHT AS DELTA T VALUES REFLECT EXTREME INSTABILITY. OTHERWISE...LOW LEVEL WINDS WILL BACK TUESDAY NIGHT INTO WEDNESDAY...ENDING LAKE EFFECT SNOW SHOWERS. KEPT TEMPERATURES COLD TUESDAY THROUGH THURSDAY. THE ECMWF APPEARS ON TRACK WITH TEMPERATURES AND APPEARS TO HANDLE THIS SCENARIO VERY WELL. THE COLDEST TEMPERATURES SHOULD BE TUESDAY NIGHT WITH LOWS FALLING INTO THE LOWER 20S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY) ISSUED AT 438 AM EST SAT NOV 9 2013 VFR FCST THIS PD. FAIRLY PRONOUNCED RISE/FALL COUPLET MIGRATING THROUGH THE WRN LAKES THIS MORNING W/SFC GUSTS SURPRISING TO THE UPSIDE AS MID-HIGH CLD CVR IN ASSOCN/W UPR TROUGH SWINGING THROUGH THE NRN LAKES AND SWRLY LL WAA SQUELCHING ANY BNDRY LYR COOLING. PEAK GUSTS XPCD IN 15-18Z TIME FRAME COINCIDENT W/MAXIMIZED MOMENTUM XFER AFT RAPID MID MORNING MIXOUT. BASED ON UPSTREAM OBS AS OF 09Z...MAY NEED TO BEST PRIOR TAF FCST WINDS A BIT AGAIN ESP AT KFWA AS CORE OF LLJ PERSISTS OVERHEAD. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LMZ043-046. && $$ SYNOPSIS...T SHORT TERM...T LONG TERM...SKIPPER AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
757 PM EST SUN NOV 10 2013 .SYNOPSIS... L0W PRESSURE IN THE GULF OF MAINE WILL TRACK EAST INTO THE MARITIMES TONIGHT AND MONDAY. WEAK HIGH PRESSURE WILL BRIEFLY BUILD OVER THE AREA MONDAY THEN A STRONG COLD FRONT WILL CROSS THE STATE MONDAY NIGHT.&& .NEAR TERM /THROUGH MONDAY/... UPDATE 1955 EDT: CANCELLED WINTER WEATHER ADVISORY BASED ON OBSERVATIONS...RADAR...AND SHORT TERM MODEL TRENDS. LITTLE OR NO ADDITIONAL ACCUMULATIONS ARE EXPECTED. UPDATED ZONES ACCORDINGLY. UPDATE 1800 EDT: A BAND OF LIGHT TO MODERATE SNOW CONTINUES TO WEAKEN ACROSS THE CROWN OF MAINE AS OF 6 PM. ANOTHER BAND OF MAINLY LIGHT SNOW FROM MILLINOCKET TO DANFORTH WAS LIFTING NORTHWARD. BASED ON RADAR TRENDS AND THE LATEST HRRR MODEL GUIDANCE WILL CONTINUE THE WINTER WEATHER ADVISORY FOR ZONES 1>6. THE HRRR SHOWS THE STEADY SNOW ENDING BY 03 UTC/10 PM FOR ALL ZONES. WILL REEVALUATE THE ADVISORY END TIME FOR NORTHEAST ZONES BY 9 PM. LOW PRESSURE WILL CONTINUE TO REDEVELOP ALONG THE COAST WITH SNOW CONTINUING TO AFFECT NORTHERN PARTS OF THE FORECAST AREA INTO THIS EVENING IN ASSOCIATION WITH THE MID AND UPPER LEVEL LOW AS IT MOVES THROUGH...SNOW WILL BE HEAVIEST AND STEADIEST OVER EASTERN AROOSTOOK COUNTY BETWEEN PRESQUE ISLE AND HOULTON WHERE ANOTHER 1-3 INCHES WILLB BE POSSIBLE IN ADDITION TO WHAT HAS ALREADY FALLEN. FURTHER SOUTH THE STEADIEST AND HEAVIEST PRECIPITATION HAS COME TO AN END WITH LINGERING RAIN/SNOW SHOWERS WINDING DOWN THROUGH THIS EVENING AS TEMPERATURES BEGIN TO COOL. FLURRIES AND SNOW SHOWERS WILL CONTINUE TO AFFECT NORTHERN AND WESTERN AREAS OVERNIGHT BUT ANY ADDITIONAL ACCUMULATION AFTER MIDNIGHT WILL BE MINOR IF ANY. THESE FLURRIES WIND DOWN MONDAY MORNING WITH OTHERWISE DRY WEATHER EXPECTED MONDAY UNDER A MIX OF SUN AND CLOUDS SOUTH AND MAINLY CLOUDY SKIES NORTH.&& && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... A DEEP TROUGH OF LOW PRESSURE TRACKING INTO QUEBEC MONDAY NIGHT WILL PULL A STRONG COLD FRONT TOWARD THE REGION. THE FRONT WILL CROSS THE AREA LATE MONDAY EVENING. SNOW SHOWERS AND POSSIBLY A BRIEF HEAVIER SNOW SQUALL WILL MOVE THROUGH CENTRAL AND NORTHERN AREAS AS THE FRONT PUSHES ACROSS MONDAY EVENING. SOME RAIN SHOWERS ARE POSSIBLE DOWNEAST. GUSTY WEST TO SOUTHWEST WINDS WILL THEN BRING IN COLDER AIR LATER MONDAY NIGHT. WET ROADS MAY BECOME ICY AS TEMPS FALL MONDAY NIGHT AND SKIES PARTIALLY CLEAR. TUESDAY WILL BE BLUSTERY AND COLD AS THE TROUGH MOVES BY TO THE NORTH. TEMPS WILL REMAIN BELOW FREEZING OVER CENTRAL AND NORTHERN AREAS AND WIND CHILLS MAY REMAIN IN THE TEENS IN MANY SPOTS. SOME FLURRIES ARE LIKELY ACROSS THE FAR NORTH AND HIGHER ELEVATIONS TO THE WEST. THIS WILL BE FOLLOWED BY A CLEAR TO PARTLY CLOUDY AND COLD NIGHT TUESDAY NIGHT WITH A BREEZE LIKELY CONTINUING. SOME WARM ADVECTION WILL BRING A MOSTLY CLOUDY DAY OVER THE NORTH WEDNESDAY WHERE SOME SNOW SHOWERS MAY BE AROUND ACROSS MAINLY HIGHER ELEVATIONS. DOWNEAST WILL BE CLEAR TO PARTLY CLOUDY ON WEDNESDAY AND A CHILLY BREEZE WILL CONTINUE ACROSS THE REGION AS HIGH PRESSURE BUILDS TOWARD THE MID ATLANTIC COAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A LARGE AREA OF HIGH PRESSURE WILL BE SETTLING ONTO THE EAST COAST THROUGH THE LAKE WEEK PERIOD BRINGING A STRETCH OF DRY WEATHER. SKIES WILL BECOME MOSTLY CLEAR WEDNESDAY NIGHT AND A LIGHT SOUTHWESTERLY BREEZE MAY CONTINUE. THURSDAY INTO FRIDAY WILL THEN BE MOSTLY SUNNY DOWNEAST AND SUNNY TO PARTLY CLOUDY OVER THE NORTH. TEMPS WILL MODERATE A BIT THROUGH THE END OF THE WEEK BEING A COUPLE DEGREES WARMER FRIDAY THAN ON THURSDAY. DRY AND SEASONABLE WEATHER WILL CONTINUE SATURDAY. THE HIGH WILL MOVE EAST OF THE AREA SUNDAY AS SOME WARM ADVECTION MOISTURE BRINGS INCREASING CLOUDS. SOME SHOWERS WILL BE POSSIBLE LATE SUNDAY ESPECIALLY IN WESTERN AREAS AS THE MOISTURE BUILDS INTO THE AREA. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... NEAR TERM: EXPECT MAINLY IFR IN THE NORTH THROUGH AFTERNOON IN SNOW WITH IMPROVEMENT TO MVFR LATER THIS EVENING INTO THE OVERNIGHT AS SNOW WINDS DOWN AND EVENTUAL IMPROVEMENT TO VFR HEADING INTO MONDAY. FOR THE SOUTHERN TERMINALS THE STEADIEST PRECIPITATION HAS MOVED OUT HOWEVER STILL EXPECT STRATUS TO BRING MVFR/IFR INTO THIS EVENING WITH CONDITIONS IMPROVING TO VFR BY LATER TONIGHT. SHORT TERM: MVFR CONDITIONS MONDAY EVENING MAY BRIEFLY LOWER TO IFR IN SNOW SHOWERS NORTH AND RAIN SHOWERS DOWNEAST LATE MONDAY EVENING. CONDITIONS SHOULD THEN IMPROVE TO VFR LATE MONDAY NIGHT. TUESDAY WILL BRING VFR CONDITIONS DOWNEAST AND VFR TO MVFR CONDITIONS OVER THE NORTH WITH STRONG GUSTY WINDS. VFR CONDITIONS ARE EXPECTED TUESDAY NIGHT. CONDITIONS WILL REMAIN VFR DOWNEAST ON WEDNESDAY BUT MAY BECOME MVFR IN SOME STRATUS ACROSS THE NORTH ON WEDNESDAY. VFR CONDITIONS ARE THEN EXPECTED THURSDAY INTO SATURDAY AS HIGH PRESSURE BUILDS SOUTH OF THE AREA. && .MARINE... NEAR TERM: WINDS/SEAS WILL INCREASE TO SCA LEVELS INTO EARLY THIS EVENING WITH THESE CONDITIONS CONTINUING THROUGH MONDAY MORNING BEFORE DIMINISHING IN THE AFTERNOON. SHORT TERM: A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED MONDAY NIGHT THROUGH TUESDAY NIGHT FOR WINDS GUSTING UP TO 30 KT. WINDS WILL THEN LIKELY DROP BELOW SCA ON WEDNESDAY AND REMAIN BELOW SCA THROUGH LATE WEEK AS HIGH PRESSURE MOVES OFF THE MID ATLC COAST. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST MONDAY FOR ANZ050>052. && $$ NEAR TERM...FITZSIMMONS/OKULSKI SHORT TERM...BLOOMER LONG TERM...BLOOMER AVIATION...FITZSIMMONS/OKULSKI/BLOOMER MARINE...FITZSIMMONS/OKULSKI/BLOOMER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1252 PM EST SAT NOV 9 2013 .SYNOPSIS... SURFACE HIGH PRESSURE WILL SLOWLY BUILD TOWARD THE REGION TODAY. LOW PRESSURE FROM CENTRAL CANADA WILL APPROACH TONIGHT AND CROSS THE REGION ON SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... CLOUD COVER WILL SLOWLY ERODE LATE THIS AFTERNOON FROM SOUTH TO NORTH AND ALLOW SOME CLEARING TONIGHT WITH LOWS DIPPING TO THE LOW TO MID 20S NORTH AND UPPER 20S TO AROUND 30F FOR BANGOR AND DOWN EAST. OTHERWISE...THE FOCUS IS ON SUNDAY`S SYSTEM. THE LOW PRESSURE SYSTEM WILL INTENSIFY SOUTHEAST OF MAINE LATER SUNDAY WHILE A SURFACE LOW IN QUEBEC FILLS. AS THE UPPER TROUGH SHARPENS AND TAKES ON A NEGATIVE TILT...PRECIPITATION WILL INCREASE DURING SUNDAY AFTERNOON FOR WASHINGTON COUNTY AND ALONG THE EASTERN BORDER NORTH TO THE SJV. WHILE MANY AREAS NORTH OF BANGOR WILL GET A QUICK INCH OF SNOW IN THE MORNING...WARM AIR ADVECTION AND THE RESULTING WARM BOUNDARY LAYER IS EXPECTED TO KEEP PRECIPITATION MOSTLY RAIN SOUTH OF HOULTON AND THE KATAHDIN REGION. IN NORTHERN AROOSTOOK COUNTY...CRITICAL THICKNESSES AND BOUNDARY LAYER CONDITIONS ARE EXPECTED TO SUPPORT ALL SNOW FOR THE ENTIRE DAY. WITH INSTABILITY ALOFT...GOOD DENDRITIC GROWTH AND THE POTENTIAL FOR BANDED SNOW IN NE MAINE...HAVE INCREASED THE SNOWFALL FORECAST TOWARDS 2 TO 4 INCHES IN NE AROOSTOOK COUNTY. AS ALWAYS WITH EARLY SEASON SNOWS...ELEVATION WILL PLAY A LARGE ROLE WITH THE HIGHER AMOUNTS ABOVE 1000 FT. PREVIOUS DISCUSSION A BAND OF SNOW SHOWERS WAS AFFECTING POTIONS OF NORTHERN AND NORTHEASTERN AROOSTOOK COUNTY EARLY THIS MORNING. LATEST HRRR MODEL SUGGESTS THAT THESE SHOULD DIMINISH BY SUNRISE. HAVE INCLUDED A SLIGHT CHANCE FOR SNOW SHOWERS FOR THE PRE-DAWN HOURS THIS MORNING. ANY SNOW ACCUMULATION WILL BE LESS THAN AN INCH. A TROF OF LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES EARLY TODAY. HIGH PRESSURE CENTERED ACROSS THE MID ATLANTIC REGION WILL SLIDE EAST TODAY WITH SURFACE RIDGING EXTENDED NORTH ACROSS THE REGION THIS AFTERNOON AND INTO THIS EVENING. AFTER A MOSTLY CLOUDY START...WE SHOULD BEGIN TO SEE DRIER AIR WORKING INTO THE REGION BY THIS AFTERNOON WITH SKIES BECOMING PARTLY TO MOSTLY SUNNY ACROSS THE NORTH AND PARTLY CLOUDY DOWNEAST. GUSTY NORTHWEST WINDS EARLY TODAY SHOULD BEGIN TO DIMINISH LATER THIS AFTERNOON AS THE RIDGE STARTS TO BUILD ACROSS THE REGION. HIGH TEMPERATURES TODAY WILL BE NEAR TO SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR. HIGHS WILL RANGE FROM THE MID/UPPER 30S NORTH AND UPPER 30S TO LOWER 40S CENTRAL AND DOWNEAST. AFTER A MAINLY CLEAR START THIS EVENING...CLOUDS WILL QUICKLY BEGIN TO INCREASE IN ADVANCE OF LOW PRESSURE TRACKING EAST ACROSS THE UPPER GREAT LAKES REGION. LIGHT PRECIPITATION IN THE FORM OF SNOW WILL BEGIN TO OVERSPREAD THE REGION BEFORE DAYBREAK SUNDAY ACROSS MOST AREAS. ALONG THE DOWNEAST COAST THE PRECIPITATION MAY INITIALLY START AS SNOW AND THEN MIX WITH OR CHANGE TO RAIN BY DAYBREAK. LOWS TONIGHT WILL OCCUR EARLY THIS EVENING AND THEN LEVEL OFF OR SLOWLY RISE AS CLOUDS CONTINUE TO THICKEN OVERNIGHT. LOWS TONIGHT WILL RANGE FROM THE MID 20S NORTH AND LOW 30S CENTRAL AND DOWNEAST. && .SHORT TERM /SUNDAY THROUGH MONDAY/... MODELS REMAIN IN VRY GOOD AGREEMENT CONCERNING THE SYSTEM EXPECTED TO AFFECT OUR FA SUN INTO SUN EVE... PRIMARY SFC LOW PRES PROGGED OVR SWRN QUEBEC AT 12Z SUN W/ AN ATTENDANT OCLD FRONT XTNDG SEWRD ACROSS NWRN-SERN NEW ENGLAND. THIS LOW IS FCST TO THEN MV EWRD ACROSS SRN QUEBEC ON SUN W/ MODEL CONSENSUS SUGGESTING SOME SECONDARY TRIPLE POINT LOW DVLPMNT VCNTY OF SERN MAINE/NERN BAY OF FUNDY BY SUN EVE. EXPECT A SWATH OF PRECIP N AND E OF THE SFC OCLN TO AFFECT THE AREA ON SUN W/ LIKELY TO CAT POPS SPREADING ENEWRD ACROSS MUCH OF THE AREA SUN AM THEN EXITING THE FA LATE SUN/SUN EVE. BNDRY LAYER TEMPS/CRITICAL THICKNESS STILL SUGGEST MAINLY RAIN DOWNEAST/A MX OF RAIN/SNOW CENTRAL AND MAINLY WET SNOW N. QPF FCSTS STILL SUPPORT .2-.3 INCHES OF LIQUID W/ SEVERAL INCHES OF SNOW PSBL N AND W SPCLY HYR TERRAIN. PRECIP SHUTS OFF QUICKLY FOLLOWING PASSAGE OF THE SFC OCNL FROM SW-NE LATE SUN W/ A RIDGE OF SFC HIGH PRES THEN EXPECTED TO BRIEFLY BUILD OVR THE FA SUN NGT INTO MON. TEMPS WILL REMAIN A BIT BLO SEASONAL NORMS ON SUN BUT EXPECT QUITE A BIT OF CLDS TO LINGER SUN NGT LIKELY KEEPING TEMPS FROM FALLING SIGNIFICANTLY. WEAK WAA ON MON AHEAD OF THE NXT SYSTEM SUGGESTS TEMPS WILL WARM A BIT TO NR SEASONAL NORMS... && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... A SFC RIDGE OF HIGH PRES OVR THE REGION MON EVE WILL SHIFT E AS A STRONG COLD FRONT APPROACHES FROM THE NW... THIS FRONT IS PROGGED TO CROSS THE FA MON NGT/ERLY TUE W/ COLD AND DRY CANADIAN AIR TO FOLLOW FOR TUE. THIS PTRN WILL REMAIN IN CONTROL THRU MID WEEK THE RETURN FLOW SUGGESTS MODERATING TEMPS FOR THE LATTER PORTION OF THE WEEK. PTRN APPEARS TO REMAIN DRY THRU THE PD HOWEVER AS ALL MODELS NOW AGREE THAT ANY COASTAL SYSTEM LATER IN THE WEEK WILL REMAIN WELL S AND E OF THE AREA. POPULATED THE LONG TERM GRIDS W/ THE XTND SUPER BLEND CONSENSUS W/ NO MAJOR CHANGES MADE... && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... NEAR TERM: MVFR CIGS AND SCT -SHSN CAN BE EXPECTED AT KFVE/KCAR/KPQI/KHUL EARLY THIS MORNING WITH VFR CIGS KBGR/KBHB. THE NORTHERN TERMINALS SHOULD ALL GO TO VFR BY LATER THIS MORNING. VFR CONDITIONS WILL START THINGS THIS EVENING WITH CONDITIONS BECOMING MVFR AFT 06Z SUN MRNG IN CIGS AND DEVELOPING -SN. SHORT TERM: TWO SYSTEMS ARE EXPECTED TO AFFECT OUR AVIATION TERMINALS SUNDAY-WED... THE FIRST INVOLVES A CANADIAN CLIPPER AND AN ATTENDANT OCLD FRONT WHICH WILL SWING ACROSS THE FA ON SUN. THIS SYSTEM WILL LIKELY PRODUCE A PD OF WDSPRD MVFR/IFR W/ RAIN S/A MX OF RAIN AND SNOW CENTRAL AND MAINLY WET SNOW N. THIS SYSTEM EXITS SUN NGT W/ A BRIEF RIDGE OF HIGH PRES FOR MON THEN A STRONG ARCTIC COLD FRONT IS EXPECTED TO CROSS THE FA MON NGT/ERLY TUE. THIS SECOND SYSTEM IS ALSO EXPECTED TO BRING A PD OF MVFR/IFR ACROSS THE AREA. OUTSIDE OF THESE 2 SYSTEMS...MAINLY VFR CONDS ARE EXPECTED THO ALWAYS THE THREAT OF SOME MVFR CIGS IN THE CAA NW FLOW IN THE WAKE OF BOTH THESE SYSTEMS ACROSS THE NRN TAF SITES... && .MARINE... UPDATE... WILL MAINTAIN END TIME FOR THE SCA AT 3PM WITH WINDS AND SEAS CONTINUING TO DIMINISH. EXPECT ISSUANCE OF A NEW SCA FOR SUNDAY AFTERNOON. NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THIS MORNING. WINDS/SEAS WILL DIMINISH BELOW SMALL CRAFT ADVISORY LEVELS THIS AFTERNOON AND REMAIN THROUGH TONIGHT. SHORT TERM: SCA CONDS ARE EXPECTED SUN INTO MON AS LOW PRES PASSES N OF THE WATERS AND DRAGS AN ATTENDANT OCLD FRONT ACROSS THE REGION... && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR ANZ050>052. && $$ NEAR TERM...DUDA/MCW SHORT TERM...KHW LONG TERM...KHW AVIATION...DUDA/MCW/KHW MARINE...DUDA/MCW/KHW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
940 AM EST SAT NOV 9 2013 .SYNOPSIS... SURFACE HIGH PRESSURE WILL SLOWLY BUILD TOWARD THE REGION TODAY. LOW PRESSURE FROM CENTRAL CANADA WILL APPROACH TONIGHT AND CROSS THE REGION ON SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... LOWERED HIGHS FOR TODAY...INCREASED CLOUD COVER IN NORTHERN ZONES AND INCREASED WIND GUSTS. OTHERWISE...THE FOCUS IS ON SUNDAY`S SYSTEM. THE LOW PRESSURE SYSTEM WILL INTENSIFY SOUTHEAST OF MAINE LATER SUNDAY WHILE A SURFACE LOW IN QUEBEC FILLS. AS THE UPPER TROUGH SHARPENS AND TAKES ON A NEGATIVE TILT...PRECIPITATION WILL INCREASE DURING SUNDAY AFTERNOON. WARM AIR ADVECTION AND THE RESULTING WARM BOUNDARY LAYER IS EXPECTED TO KEEP PRECIPITATION MOSTLY RAIN SOUTH OF HOULTON AND THE KATAHDIN REGION. HOWEVER...IN NORTHERN AROOSTOOK COUNTY...CRITICAL THICKNESSES AND BOUNDARY LAYER CONDITIONS ARE EXPECTED TO SUPPORT ALL SNOW. WITH INSTABILITY ALOFT...GOOD DENDRITIC GROWTH AND THE POTENTIAL FOR BANDED SNOW IN NE MAINE...SIGNS ARE POINTING TO INCREASING SNOWFALL FORECASTS TOWARDS 2 TO 4 INCHES OR MORE. AS ALWAYS WITH EARLY SEASON SNOWS...ELEVATION WILL PLAY A LARGE ROLE WITH THE HIGHER AMOUNTS ABOVE 1000 FT. PREVIOUS DISCUSSION A BAND OF SNOW SHOWERS WAS AFFECTING POTIONS OF NORTHERN AND NORTHEASTERN AROOSTOOK COUNTY EARLY THIS MORNING. LATEST HRRR MODEL SUGGESTS THAT THESE SHOULD DIMINISH BY SUNRISE. HAVE INCLUDED A SLIGHT CHANCE FOR SNOW SHOWERS FOR THE PRE-DAWN HOURS THIS MORNING. ANY SNOW ACCUMULATION WILL BE LESS THAN AN INCH. A TROF OF LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES EARLY TODAY. HIGH PRESSURE CENTERED ACROSS THE MID ATLANTIC REGION WILL SLIDE EAST TODAY WITH SURFACE RIDGING EXTENDED NORTH ACROSS THE REGION THIS AFTERNOON AND INTO THIS EVENING. AFTER A MOSTLY CLOUDY START...WE SHOULD BEGIN TO SEE DRIER AIR WORKING INTO THE REGION BY THIS AFTERNOON WITH SKIES BECOMING PARTLY TO MOSTLY SUNNY ACROSS THE NORTH AND PARTLY CLOUDY DOWNEAST. GUSTY NORTHWEST WINDS EARLY TODAY SHOULD BEGIN TO DIMINISH LATER THIS AFTERNOON AS THE RIDGE STARTS TO BUILD ACROSS THE REGION. HIGH TEMPERATURES TODAY WILL BE NEAR TO SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR. HIGHS WILL RANGE FROM THE MID/UPPER 30S NORTH AND UPPER 30S TO LOWER 40S CENTRAL AND DOWNEAST. AFTER A MAINLY CLEAR START THIS EVENING...CLOUDS WILL QUICKLY BEGIN TO INCREASE IN ADVANCE OF LOW PRESSURE TRACKING EAST ACROSS THE UPPER GREAT LAKES REGION. LIGHT PRECIPITATION IN THE FORM OF SNOW WILL BEGIN TO OVERSPREAD THE REGION BEFORE DAYBREAK SUNDAY ACROSS MOST AREAS. ALONG THE DOWNEAST COAST THE PRECIPITATION MAY INITIALLY START AS SNOW AND THEN MIX WITH OR CHANGE TO RAIN BY DAYBREAK. LOWS TONIGHT WILL OCCUR EARLY THIS EVENING AND THEN LEVEL OFF OR SLOWLY RISE AS CLOUDS CONTINUE TO THICKEN OVERNIGHT. LOWS TONIGHT WILL RANGE FROM THE MID 20S NORTH AND LOW 30S CENTRAL AND DOWNEAST. && .SHORT TERM /SUNDAY THROUGH MONDAY/... MODELS REMAIN IN VRY GOOD AGREEMENT CONCERNING THE SYSTEM EXPECTED TO AFFECT OUR FA SUN INTO SUN EVE... PRIMARY SFC LOW PRES PROGGED OVR SWRN QUEBEC AT 12Z SUN W/ AN ATTENDANT OCLD FRONT XTNDG SEWRD ACROSS NWRN-SERN NEW ENGLAND. THIS LOW IS FCST TO THEN MV EWRD ACROSS SRN QUEBEC ON SUN W/ MODEL CONSENSUS SUGGESTING SOME SECONDARY TRIPLE POINT LOW DVLPMNT VCNTY OF SERN MAINE/NERN BAY OF FUNDY BY SUN EVE. EXPECT A SWATH OF PRECIP N AND E OF THE SFC OCLN TO AFFECT THE AREA ON SUN W/ LIKELY TO CAT POPS SPREADING ENEWRD ACROSS MUCH OF THE AREA SUN AM THEN EXITING THE FA LATE SUN/SUN EVE. BNDRY LAYER TEMPS/CRITICAL THICKNESS STILL SUGGEST MAINLY RAIN DOWNEAST/A MX OF RAIN/SNOW CENTRAL AND MAINLY WET SNOW N. QPF FCSTS STILL SUPPORT .2-.3 INCHES OF LIQUID W/ SEVERAL INCHES OF SNOW PSBL N AND W SPCLY HYR TERRAIN. PRECIP SHUTS OFF QUICKLY FOLLOWING PASSAGE OF THE SFC OCNL FROM SW-NE LATE SUN W/ A RIDGE OF SFC HIGH PRES THEN EXPECTED TO BRIEFLY BUILD OVR THE FA SUN NGT INTO MON. TEMPS WILL REMAIN A BIT BLO SEASONAL NORMS ON SUN BUT EXPECT QUITE A BIT OF CLDS TO LINGER SUN NGT LIKELY KEEPING TEMPS FROM FALLING SIGNIFICANTLY. WEAK WAA ON MON AHEAD OF THE NXT SYSTEM SUGGESTS TEMPS WILL WARM A BIT TO NR SEASONAL NORMS... && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... A SFC RIDGE OF HIGH PRES OVR THE REGION MON EVE WILL SHIFT E AS A STRONG COLD FRONT APPROACHES FROM THE NW... THIS FRONT IS PROGGED TO CROSS THE FA MON NGT/ERLY TUE W/ COLD AND DRY CANADIAN AIR TO FOLLOW FOR TUE. THIS PTRN WILL REMAIN IN CONTROL THRU MID WEEK THE RETURN FLOW SUGGESTS MODERATING TEMPS FOR THE LATTER PORTION OF THE WEEK. PTRN APPEARS TO REMAIN DRY THRU THE PD HOWEVER AS ALL MODELS NOW AGREE THAT ANY COASTAL SYSTEM LATER IN THE WEEK WILL REMAIN WELL S AND E OF THE AREA. POPULATED THE LONG TERM GRIDS W/ THE XTND SUPER BLEND CONSENSUS W/ NO MAJOR CHANGES MADE... && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... NEAR TERM: MVFR CIGS AND SCT -SHSN CAN BE EXPECTED AT KFVE/KCAR/KPQI/KHUL EARLY THIS MORNING WITH VFR CIGS KBGR/KBHB. THE NORTHERN TERMINALS SHOULD ALL GO TO VFR BY LATER THIS MORNING. VFR CONDITIONS WILL START THINGS THIS EVENING WITH CONDITIONS BECOMING MVFR AFT 06Z SUN MRNG IN CIGS AND DEVELOPING -SN. SHORT TERM: TWO SYSTEMS ARE EXPECTED TO AFFECT OUR AVIATION TERMINALS SUNDAY-WED... THE FIRST INVOLVES A CANADIAN CLIPPER AND AN ATTENDANT OCLD FRONT WHICH WILL SWING ACROSS THE FA ON SUN. THIS SYSTEM WILL LIKELY PRODUCE A PD OF WDSPRD MVFR/IFR W/ RAIN S/A MX OF RAIN AND SNOW CENTRAL AND MAINLY WET SNOW N. THIS SYSTEM EXITS SUN NGT W/ A BRIEF RIDGE OF HIGH PRES FOR MON THEN A STRONG ARCTIC COLD FRONT IS EXPECTED TO CROSS THE FA MON NGT/ERLY TUE. THIS SECOND SYSTEM IS ALSO EXPECTED TO BRING A PD OF MVFR/IFR ACROSS THE AREA. OUTSIDE OF THESE 2 SYSTEMS...MAINLY VFR CONDS ARE EXPECTED THO ALWAYS THE THREAT OF SOME MVFR CIGS IN THE CAA NW FLOW IN THE WAKE OF BOTH THESE SYSTEMS ACROSS THE NRN TAF SITES... && .MARINE... NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THIS MORNING. WINDS/SEAS WILL DIMINISH BELOW SMALL CRAFT ADVISORY LEVELS THIS AFTERNOON AND REMAIN THROUGH TONIGHT. SHORT TERM: SCA CONDS ARE EXPECTED SUN INTO MON AS LOW PRES PASSES N OF THE WATERS AND DRAGS AN ATTENDANT OCLD FRONT ACROSS THE REGION... && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR ANZ050>052. && $$ NEAR TERM...DUDA/MCW SHORT TERM...KHW LONG TERM...KHW AVIATION...DUDA/KHW MARINE...DUDA/KHW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
618 AM EST SAT NOV 9 2013 .SYNOPSIS... SURFACE HIGH PRESSURE WILL SLOWLY BUILD TOWARD THE REGION TODAY. LOW PRESSURE FROM CENTRAL CANADA WILL APPROACH TONIGHT AND CROSS THE REGION ON SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATE...MADE MINOR ADJUSTMENTS TO SKY/POP/TEMP GRIDS FOR THE NEXT FEW HOURS BUT REST OF FORECAST STILL ON TRACK. PREVIOUS DISCUSSION A BAND OF SNOW SHOWERS WAS AFFECTING POTIONS OF NORTHERN AND NORTHEASTERN AROOSTOOK COUNTY EARLY THIS MORNING. LATEST HRRR MODEL SUGGESTS THAT THESE SHOULD DIMINISH BY SUNRISE. HAVE INCLUDED A SLIGHT CHANCE FOR SNOW SHOWERS FOR THE PRE-DAWN HOURS THIS MORNING. ANY SNOW ACCUMULATION WILL BE LESS THAN AN INCH. A TROF OF LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES EARLY TODAY. HIGH PRESSURE CENTERED ACROSS THE MID ATLANTIC REGION WILL SLIDE EAST TODAY WITH SURFACE RIDGING EXTENDED NORTH ACROSS THE REGION THIS AFTERNOON AND INTO THIS EVENING. AFTER A MOSTLY CLOUDY START...WE SHOULD BEGIN TO SEE DRIER AIR WORKING INTO THE REGION BY THIS AFTERNOON WITH SKIES BECOMING PARTLY TO MOSTLY SUNNY ACROSS THE NORTH AND PARTLY CLOUDY DOWNEAST. GUSTY NORTHWEST WINDS EARLY TODAY SHOULD BEGIN TO DIMINISH LATER THIS AFTERNOON AS THE RIDGE STARTS TO BUILD ACROSS THE REGION. HIGH TEMPERATURES TODAY WILL BE NEAR TO SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR. HIGHS WILL RANGE FROM THE MID/UPPER 30S NORTH AND UPPER 30S TO LOWER 40S CENTRAL AND DOWNEAST. AFTER A MAINLY CLEAR START THIS EVENING...CLOUDS WILL QUICKLY BEGIN TO INCREASE IN ADVANCE OF LOW PRESSURE TRACKING EAST ACROSS THE UPPER GREAT LAKES REGION. LIGHT PRECIPITATION IN THE FORM OF SNOW WILL BEGIN TO OVERSPREAD THE REGION BEFORE DAYBREAK SUNDAY ACROSS MOST AREAS. ALONG THE DOWNEAST COAST THE PRECIPITATION MAY INITIALLY START AS SNOW AND THEN MIX WITH OR CHANGE TO RAIN BY DAYBREAK. LOWS TONIGHT WILL OCCUR EARLY THIS EVENING AND THEN LEVEL OFF OR SLOWLY RISE AS CLOUDS CONTINUE TO THICKEN OVERNIGHT. LOWS TONIGHT WILL RANGE FROM THE MID 20S NORTH AND LOW 30S CENTRAL AND DOWNEAST. && .SHORT TERM /SUNDAY THROUGH MONDAY/... MODELS REMAIN IN VRY GOOD AGREEMENT CONCERNING THE SYSTEM EXPECTED TO AFFECT OUR FA SUN INTO SUN EVE... PRIMARY SFC LOW PRES PROGGED OVR SWRN QUEBEC AT 12Z SUN W/ AN ATTENDANT OCLD FRONT XTNDG SEWRD ACROSS NWRN-SERN NEW ENGLAND. THIS LOW IS FCST TO THEN MV EWRD ACROSS SRN QUEBEC ON SUN W/ MODEL CONSENSUS SUGGESTING SOME SECONDARY TRIPLE POINT LOW DVLPMNT VCNTY OF SERN MAINE/NERN BAY OF FUNDY BY SUN EVE. EXPECT A SWATH OF PRECIP N AND E OF THE SFC OCLN TO AFFECT THE AREA ON SUN W/ LIKELY TO CAT POPS SPREADING ENEWRD ACROSS MUCH OF THE AREA SUN AM THEN EXITING THE FA LATE SUN/SUN EVE. BNDRY LAYER TEMPS/CRITICAL THICKNESS STILL SUGGEST MAINLY RAIN DOWNEAST/A MX OF RAIN/SNOW CENTRAL AND MAINLY WET SNOW N. QPF FCSTS STILL SUPPORT .2-.3 INCHES OF LIQUID W/ SEVERAL INCHES OF SNOW PSBL N AND W SPCLY HYR TERRAIN. PRECIP SHUTS OFF QUICKLY FOLLOWING PASSAGE OF THE SFC OCNL FROM SW-NE LATE SUN W/ A RIDGE OF SFC HIGH PRES THEN EXPECTED TO BRIEFLY BUILD OVR THE FA SUN NGT INTO MON. TEMPS WILL REMAIN A BIT BLO SEASONAL NORMS ON SUN BUT EXPECT QUITE A BIT OF CLDS TO LINGER SUN NGT LIKELY KEEPING TEMPS FROM FALLING SIGNIFICANTLY. WEAK WAA ON MON AHEAD OF THE NXT SYSTEM SUGGESTS TEMPS WILL WARM A BIT TO NR SEASONAL NORMS... && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... A SFC RIDGE OF HIGH PRES OVR THE REGION MON EVE WILL SHIFT E AS A STRONG COLD FRONT APPROACHES FROM THE NW... THIS FRONT IS PROGGED TO CROSS THE FA MON NGT/ERLY TUE W/ COLD AND DRY CANADIAN AIR TO FOLLOW FOR TUE. THIS PTRN WILL REMAIN IN CONTROL THRU MID WEEK THE RETURN FLOW SUGGESTS MODERATING TEMPS FOR THE LATTER PORTION OF THE WEEK. PTRN APPEARS TO REMAIN DRY THRU THE PD HOWEVER AS ALL MODELS NOW AGREE THAT ANY COASTAL SYSTEM LATER IN THE WEEK WILL REMAIN WELL S AND E OF THE AREA. POPULATED THE LONG TERM GRIDS W/ THE XTND SUPER BLEND CONSENSUS W/ NO MAJOR CHANGES MADE... && .AVIATION /11Z SATURDAY THROUGH WEDNESDAY/... NEAR TERM: MVFR CIGS AND SCT -SHSN CAN BE EXPECTED AT KFVE/KCAR/KPQI/KHUL EARLY THIS MORNING WITH VFR CIGS KBGR/KBHB. THE NORTHERN TERMINALS SHOULD ALL GO TO VFR BY LATER THIS MORNING. VFR CONDITIONS WILL START THINGS THIS EVENING WITH CONDITIONS BECOMING MVFR AFT 06Z SUN MRNG IN CIGS AND DEVELOPING -SN. SHORT TERM: TWO SYSTEMS ARE EXPECTED TO AFFECT OUR AVIATION TERMINALS SUNDAY-WED... THE FIRST INVOLVES A CANADIAN CLIPPER AND AN ATTENDANT OCLD FRONT WHICH WILL SWING ACROSS THE FA ON SUN. THIS SYSTEM WILL LIKELY PRODUCE A PD OF WDSPRD MVFR/IFR W/ RAIN S/A MX OF RAIN AND SNOW CENTRAL AND MAINLY WET SNOW N. THIS SYSTEM EXITS SUN NGT W/ A BRIEF RIDGE OF HIGH PRES FOR MON THEN A STRONG ARCTIC COLD FRONT IS EXPECTED TO CROSS THE FA MON NGT/ERLY TUE. THIS SECOND SYSTEM IS ALSO EXPECTED TO BRING A PD OF MVFR/IFR ACROSS THE AREA. OUTSIDE OF THESE 2 SYSTEMS...MAINLY VFR CONDS ARE EXPECTED THO ALWAYS THE THREAT OF SOME MVFR CIGS IN THE CAA NW FLOW IN THE WAKE OF BOTH THESE SYSTEMS ACROSS THE NRN TAF SITES... && .MARINE... NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THIS MORNING. WINDS/SEAS WILL DIMINISH BELOW SMALL CRAFT ADVISORY LEVELS THIS AFTERNOON AND REMAIN THROUGH TONIGHT. SHORT TERM: SCA CONDS ARE EXPECTED SUN INTO MON AS LOW PRES PASSES N OF THE WATERS AND DRAGS AN ATTENDANT OCLD FRONT ACROSS THE REGION... && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR ANZ050>052. && $$ NEAR TERM...DUDA SHORT TERM...KHW LONG TERM...KHW AVIATION...DUDA/KHW MARINE...DUDA/KHW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
405 AM EST SAT NOV 9 2013 .SYNOPSIS... SURFACE HIGH PRESSURE WILL SLOWLY BUILD TOWARD THE REGION TODAY. LOW PRESSURE FROM CENTRAL CANADA WILL APPROACH TONIGHT AND CROSS THE REGION ON SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... A BAND OF SNOW SHOWERS WAS AFFECTING POTIONS OF NORTHERN AND NORTHEASTERN AROOSTOOK COUNTY EARLY THIS MORNING. LATEST HRRR MODEL SUGGESTS THAT THESE SHOULD DIMINISH BY SUNRISE. HAVE INCLUDED A SLIGHT CHANCE FOR SNOW SHOWERS FOR THE PRE-DAWN HOURS THIS MORNING. ANY SNOW ACCUMULATION WILL BE LESS THAN AN INCH. A TROF OF LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES EARLY TODAY. HIGH PRESSURE CENTERED ACROSS THE MID ATLANTIC REGION WILL SLIDE EAST TODAY WITH SURFACE RIDGING EXTENDED NORTH ACROSS THE REGION THIS AFTERNOON AND INTO THIS EVENING. AFTER A MOSTLY CLOUDY START...WE SHOULD BEGIN TO SEE DRIER AIR WORKING INTO THE REGION BY THIS AFTERNOON WITH SKIES BECOMING PARTLY TO MOSTLY SUNNY ACROSS THE NORTH AND PARTLY CLOUDY DOWNEAST. GUSTY NORTHWEST WINDS EARLY TODAY SHOULD BEGIN TO DIMINISH LATER THIS AFTERNOON AS THE RIDGE STARTS TO BUILD ACROSS THE REGION. HIGH TEMPERATURES TODAY WILL BE NEAR TO SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR. HIGHS WILL RANGE FROM THE MID/UPPER 30S NORTH AND UPPER 30S TO LOWER 40S CENTRAL AND DOWNEAST. AFTER A MAINLY CLEAR START THIS EVENING...CLOUDS WILL QUICKLY BEGIN TO INCREASE IN ADVANCE OF LOW PRESSURE TRACKING EAST ACROSS THE UPPER GREAT LAKES REGION. LIGHT PRECIPITATION IN THE FORM OF SNOW WILL BEGIN TO OVERSPREAD THE REGION BEFORE DAYBREAK SUNDAY ACROSS MOST AREAS. ALONG THE DOWNEAST COAST THE PRECIPITATION MAY INITIALLY START AS SNOW AND THEN MIX WITH OR CHANGE TO RAIN BY DAYBREAK. LOWS TONIGHT WILL OCCUR EARLY THIS EVENING AND THEN LEVEL OFF OR SLOWLY RISE AS CLOUDS CONTINUE TO THICKEN OVERNIGHT. LOWS TONIGHT WILL RANGE FROM THE MID 20S NORTH AND LOW 30S CENTRAL AND DOWNEAST. && .SHORT TERM /SUNDAY THROUGH MONDAY/... MODELS REMAIN IN VRY GOOD AGREEMENT CONCERNING THE SYSTEM EXPECTED TO AFFECT OUR FA SUN INTO SUN EVE... PRIMARY SFC LOW PRES PROGGED OVR SWRN QUEBEC AT 12Z SUN W/ AN ATTENDANT OCLD FRONT XTNDG SEWRD ACROSS NWRN-SERN NEW ENGLAND. THIS LOW IS FCST TO THEN MV EWRD ACROSS SRN QUEBEC ON SUN W/ MODEL CONSENSUS SUGGESTING SOME SECONDARY TRIPLE POINT LOW DVLPMNT VCNTY OF SERN MAINE/NERN BAY OF FUNDY BY SUN EVE. EXPECT A SWATH OF PRECIP N AND E OF THE SFC OCLN TO AFFECT THE AREA ON SUN W/ LIKELY TO CAT POPS SPREADING ENEWRD ACROSS MUCH OF THE AREA SUN AM THEN EXITING THE FA LATE SUN/SUN EVE. BNDRY LAYER TEMPS/CRITICAL THICKNESS STILL SUGGEST MAINLY RAIN DOWNEAST/A MX OF RAIN/SNOW CENTRAL AND MAINLY WET SNOW N. QPF FCSTS STILL SUPPORT .2-.3 INCHES OF LIQUID W/ SEVERAL INCHES OF SNOW PSBL N AND W SPCLY HYR TERRAIN. PRECIP SHUTS OFF QUICKLY FOLLOWING PASSAGE OF THE SFC OCNL FROM SW-NE LATE SUN W/ A RIDGE OF SFC HIGH PRES THEN EXPECTED TO BRIEFLY BUILD OVR THE FA SUN NGT INTO MON. TEMPS WILL REMAIN A BIT BLO SEASONAL NORMS ON SUN BUT EXPECT QUITE A BIT OF CLDS TO LINGER SUN NGT LIKELY KEEPING TEMPS FROM FALLING SIGNIFICANTLY. WEAK WAA ON MON AHEAD OF THE NXT SYSTEM SUGGESTS TEMPS WILL WARM A BIT TO NR SEASONAL NORMS... && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... A SFC RIDGE OF HIGH PRES OVR THE REGION MON EVE WILL SHIFT E AS A STRONG COLD FRONT APPROACHES FROM THE NW... THIS FRONT IS PROGGED TO CROSS THE FA MON NGT/ERLY TUE W/ COLD AND DRY CANADIAN AIR TO FOLLOW FOR TUE. THIS PTRN WILL REMAIN IN CONTROL THRU MID WEEK THE RETURN FLOW SUGGESTS MODERATING TEMPS FOR THE LATTER PORTION OF THE WEEK. PTRN APPEARS TO REMAIN DRY THRU THE PD HOWEVER AS ALL MODELS NOW AGREE THAT ANY COASTAL SYSTEM LATER IN THE WEEK WILL REMAIN WELL S AND E OF THE AREA. POPULATED THE LONG TERM GRIDS W/ THE XTND SUPER BLEND CONSENSUS W/ NO MAJOR CHANGES MADE... && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... NEAR TERM: MVFR CIGS AND SCT -SHSN CAN BE EXPECTED AT KFVE/KCAR/KPQI/KHUL EARLY THIS MORNING WITH VFR CIGS KBGR/KBHB. THE NORTHERN TERMINALS SHOULD ALL GO TO VFR BY LATER THIS MORNING. VFR CONDITIONS WILL START THINGS THIS EVENING WITH CONDITIONS BECOMING MVFR AFT 06Z SUN MRNG IN CIGS AND DEVELOPING -SN. SHORT TERM: TWO SYSTEMS ARE EXPECTED TO AFFECT OUR AVIATION TERMINALS SUNDAY-WED... THE FIRST INVOLVES A CANADIAN CLIPPER AND AN ATTENDANT OCLD FRONT WHICH WILL SWING ACROSS THE FA ON SUN. THIS SYSTEM WILL LIKELY PRODUCE A PD OF WDSPRD MVFR/IFR W/ RAIN S/A MX OF RAIN AND SNOW CENTRAL AND MAINLY WET SNOW N. THIS SYSTEM EXITS SUN NGT W/ A BRIEF RIDGE OF HIGH PRES FOR MON THEN A STRONG ARCTIC COLD FRONT IS EXPECTED TO CROSS THE FA MON NGT/ERLY TUE. THIS SECOND SYSTEM IS ALSO EXPECTED TO BRING A PD OF MVFR/IFR ACROSS THE AREA. OUTSIDE OF THESE 2 SYSTEMS...MAINLY VFR CONDS ARE EXPECTED THO ALWAYS THE THREAT OF SOME MVFR CIGS IN THE CAA NW FLOW IN THE WAKE OF BOTH THESE SYSTEMS ACROSS THE NRN TAF SITES... && .MARINE... NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THIS MORNING. WINDS/SEAS WILL DIMINISH BELOW SMALL CRAFT ADVISORY LEVELS THIS AFTERNOON AND REMAIN THROUGH TONIGHT. SHORT TERM: SCA CONDS ARE EXPECTED SUN INTO MON AS LOW PRES PASSES N OF THE WATERS AND DRAGS AN ATTENDANT OCLD FRONT ACROSS THE REGION... && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR ANZ050>052. && $$ NEAR TERM...DUDA SHORT TERM...KHW LONG TERM...KHW AVIATION...DUDA/KHW MARINE...DUDA/KHW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
411 PM EST SAT NOV 9 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 400 PM EST SAT NOV 9 2013 LOOKING AT WV IMAGERY...THE FIRST SHORTWAVE THAT MOVED THROUGH THE REGION EARLY THIS MORNING HAS SHIFTED EAST INTO FAR SOUTHEASTERN ONTARIO WHILE A SECOND SHORTWAVE IS CURRENTLY SLIDING EAST ACROSS NORTHERN LOWER MICHIGAN. AT THE SURFACE...A 1000MB LOW CURRENTLY OVER EASTERN LAKE SUPERIOR WILL SLIDE EAST TONIGHT...ALLOWING COOLER 850MB TEMPS...FALLING FROM CURRENT VALUES OF -3 TO -5C (NORTHEAST AND SOUTHWEST LAKE SUPERIOR RESPECTIVELY) ON RAP ANALYSIS TO -7.5C BY 12Z SUNDAY. THIS COLDER AIR...COMBINED WITH LINGERING DEEP MOISTURE FROM THE LOW SHOULD LEAD TO AN INCREASE IN LAKE ENHANCED PRECIPITATION THIS EVENING. IN ADDITION...A SHORTWAVE CURRENTLY DROPPING SOUTHEAST FROM CENTRAL SASKATCHEWAN WILL SLIDE ACROSS THE CWA THIS EVENING AND AID THE PRECIPITATION. AT THE PRESENT TIME...MAINLY RAIN SHOWERS (AT LEAST BASED OFF WEBCAMS) ARE OVER THE NORTHWEST HALF OF UPPER MICHIGAN ALONG THE NORTHERN EDGE OF THE COLDER AIR SLIDING EAST ALONG THE MI/WI BORDER. THIS PRECIPITATION SHOULD CONTINUE EAST OVER THE NEXT SEVERAL HOURS. A SURFACE TROUGH THEN SWEEPS SOUTHEAST BEHIND THE LOW THIS EVENING AND SHIFT WINDS FROM THE WEST TO THE NORTHWEST. ALONG AND SHORTLY AFTER THIS MOVES THROUGH IS WHEN THE STRONGEST SHOWERS WILL OCCUR DUE TO FORCING FROM THE TROUGH AND THEN LAKE ENHANCEMENT ON THE BACK SIDE OF THE TROUGH. LAKE ENHANCEMENT WON/T BE TOO LARGE OF A FACTOR...SINCE 850MB TEMPS DO WARM SLIGHTLY (TO -4C) BEFORE FALLING TOWARDS SUNDAY MORNING. EVEN WITH INVERSION HEIGHTS GENERALLY IN THE 5-7KFT...THE MARGINAL DELTA-T VALUES OF 11-14 SHOW UP IN THE LAKE INDUCED CAPE VALUES ONLY AROUND 100-150J/KG. THE MOST FAVORABLE TIME FOR LAKE ENHANCEMENT WILL ACTUALLY BE AROUND THE TIME THE DEEPEST MOISTURE WILL BE DEPARTING LATE TONIGHT. EVEN WITH THE LIMITING FACTOR OF THE LAKE ENHANCEMENT...THERE SHOULD BE A FEW HOUR PERIOD OF STRONGER UPSLOPE SHOWERS IN THE NORTHWEST WIND FAVORED LOCATIONS OVER NORTHWESTERN UPPER MICHIGAN THIS EVENING AND THEN OVER THE EAST DURING THE OVERNIGHT HOURS. THE LAKE EFFECT SNOW PARAMETER HIGHLIGHTS THIS IDEA FAIRLY WELL IN THE LATE EVENING AND EARLY OVERNIGHT HOURS AND HAVE THE HIGHEST POPS DURING THAT TIMEFRAME. AS FOR QPF...HAVE MOST LOCATIONS OVER THE WEST BETWEEN 0.1-0.4INCH WITH THE HIGHEST VALUES OVER THE SPINE OF THE KEWEENAW PENINSULA AND THE WESTERN SLOPES OF THE HURON MOUNTAINS. FARTHER EAST...ONLY HAVE A 0.1-0.2IN OVER THE NORTHWEST WIND FAVORED LOCATIONS OVER THE EAST DUE TO THE LATER ARRIVAL OF THE SURFACE TROUGH. SINCE IT WILL BE COLD ENOUGH FOR SNOW ALOFT...PRECIPITATION TYPE COMES DOWN TO THE NEAR SURFACE TEMPERATURES. LOOKING AT LOW LEVEL TEMPERATURES IN SOUNDINGS AND WETBULB ZERO HEIGHTS...THINK THERE WILL BE A MIX OF RAIN SNOW NEAR LAKE SUPERIOR AND OVER THE KEWEENAW/EAST IN THE EVENING. BUT AS THE DIURNAL COOLING AND COLDER AIR DROPPING IN TONIGHT...EXPECT A CHANGE OVER TO ALL SNOW IN MOST LOCATIONS OVERNIGHT. SNOW RATIOS SHOULD STAY ON THE LOW SIDE...AROUND 10-1 THROUGH THE NIGHT SINCE BUFKIT SOUNDINGS ARE SHOWING THE CLOUD LAYER STAYING BELOW THE DGZ THROUGH THE NIGHT. THUS...HAVE A GENERAL 1-2 INCHES OVER THE INTERIOR WEST EXCEPT THE FAVORED UPSLOPE AREAS NEAR TWIN LAKES WHERE 2-3 INCHES COULD FALL. OVER THE WESTERN SLOPES OF THE HURON MOUNTAINS...COULD SEE AMOUNTS IN THE 3-4 INCH RANGE...BUT WILL NOT ISSUE AN ADVISORY FOR BARAGA COUNTY DUE TO THE LIMITED POPULATION IMPACT (MOST OF THE POPULATION WILL SEE UNDER 2 INCHES). DO HAVE SOME UNCERTAINTY ON AMOUNTS ALONG THE SPINE OF THE KEWEENAW...AS MODELS ARE SHOWING WETBULB0 VALUES FALLING BELOW 700FT BUT SURFACE TEMPERATURES STAYING IN THE MID 30S. SINCE THERE IS LITTLE SNOW ON THE GROUND ON WEBCAMS...WONDERING HOW MUCH ACCUMULATION WILL OCCUR. DID GO WITH 1-1.5IN ALONG THE HIGHEST ELEVATION LOCATIONS...WHICH IS A GOOD IN BETWEEN VALUE BASED ON THE BORDERLINE TEMPERATURES. A HIGH PRESSURE RIDGE WILL BEGIN SLIDING OVER THE FAR WEST LATE TONIGHT AND PROCEED TO CROSS THE REST OF THE CWA DURING THE DAY ON SUNDAY. THIS INCREASE IN DRIER AIR...SUBSIDENCE...AND BACKING WINDS WILL LEAD TO DECREASING SHOWERS FROM WEST TO EAST LATE TONIGHT AND THROUGH THE DAY ON SUNDAY. THINK THERE WILL BE A FAIRLY QUICK DIMINISHING TREND DUE TO THE MARGINAL DELTA-T VALUES FOR PURE LAKE EFFECT...SO ONCE THE DEEPER MOISTURE PULLS OUT THE SHOWERS SHOULD FALL APART AND HAVE SHOWN THAT IDEA WITH THE POPS THROUGH THE DAY. FORESEE SOME PEAKS OF SUN OVER THE INTERIOR SOUTH CENTRAL LOCATIONS DURING THE MORNING...BEFORE MID/HIGH CLOUDS BEGIN TO STREAM IN AHEAD OF THE NEXT TROUGH THAT WILL PASS THROUGH ON SUNDAY NIGHT. HIGHS ON SUNDAY WILL BE IN THE UPPER 30S WEST AND AROUND 40 EAST. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 400 PM EST SAT NOV 9 2013 A SHARP CHANGE TO WINTER WEATHER WILL BE IN THE OFFERING EARLY IN THE FORECAST PERIOD AS A STRONG COLD FRONT WILL PASS ACROSS THE AREA SUNDAY NIGHT. THIS WILL ALLOW THE COLDEST AIRMASS BY FAR OF THE SEASON TO MOVE ACROSS THE GREAT LAKES...WITH LAKE EFFECT SNOWFALL DEVELOPING IN EARNEST MONDAY AND CONTINUING INTO TUESDAY...ESPECIALLY EAST OF MARQUETTE. IN ADDITION...WINDY N-NW WINDS ARE EXPECTED BEHIND THE FRONT ALLOWING FOR BLOWING AND DRIFTING SNOW. AS FOR THE SPECIFICS...THE MODELS ARE IN EXCELLENT AGREEMENT WITH THE PATTERN SUNDAY NIGHT-TUESDAY. ALTHOUGH THE GFS MAY BE ABOUT 3 HR FASTER WITH THE FRONTAL PASSAGE...THE MODELS ARE IN VERY GOOD AGREEMENT IN SHOWING A NARROW BAND OF MOISTURE ACCOMPANYING THE FRONT SUNDAY NIGHT. ALTHOUGH THE FRONT WILL BE FAIRLY FAST MOVING...THE MODELS SUGGEST THAT UP TO 0.10 INCH OF PCPN WILL FALL WITH THE FRONT. WITH 850MB TEMPS AROUND -4C...EXPECT MOST OF THIS TO FALL AS SNOW EXCEPT NEAR THE LAKE. COULD SEE UP TO AN INCH OF SNOW ACROSS MUCH OF THE U.P. WITH WESTERN PARTS PERHAPS SEEING TWO INCHES WITH SOME FAVORABLE UPSLOPE FLOW. THEN...STRONG COLD ADVECTION AS THE ARCTIC HIGH BUILDS ACROSS THE NRN PLAINS/UPPER MS VLY WILL ALLOW 850MB TEMPS TO DROP TO -16C. THIS WILL YIELD GREAT AMOUNTS OF LAKE INDUCED INSTABILITY WITH LOW LEVEL LAPSE OF OVER 9C/KM AND INVERSION HEIGHTS AROUND 3 KM BY MONDAY AFTERNOON. THIS TYPE OF THERMODYNAMIC PROFILE WOULD SUGGEST THAT LAKE EFFECT MAY BECOME HEAVY AT TIMES...ESPECIALLY MONDAY INTO MONDAY NIGHT EAST OF MARQUETTE WHERE THE FETCH WILL BE THE LONGEST OWING TO N-NW PBL FLOW. HOWEVER...THE INTERESTING PROBLEM WITH THIS LES EVENT WILL BE THE EXTRAORDINARY HIGH PRESSURE AROUND 1047MB (OR OVER +3 STANDARD DEVIATION FROM THE MEAN) BUILDING ACROSS THE AREA IMMEDIATELY BEHIND THE FRONT. NOT ONLY WILL THIS LEAD TO QUITE WINDY CONDITIONS ACROSS MUCH OF THE FORECAST AREA...ESPECIALLY CLOSE TO LAKE SUPERIOR...BUT IT WILL ALSO USHER IN DRY AIR ALOFT AND STRONG SYNOPTIC SCALE SUBSIDENCE. IN ESSENCE...THIS EVENT WILL BE MORE LIKE A PURE LES EVENT IN JANUARY VS THE NORMAL LAKE ENHANCED EVENTS THAT WE NORMALLY SEE IN NOVEMBER. WILL PROBABLY SEE VERY DISTINCT LES BANDS DEVELOPING MONDAY AND CONTINUING INTO MONDAY NIGHT. THESE BANDS HAVE THE POTENTIAL TO DROP A SIGNIFICANT AMOUNT OF SNOW...HOWEVER THE CONCERN IS THAT THESE BANDS WILL BE SOMEWHAT TRANSIENT WITH THE PBL WINDS SHIFTING FROM AROUND 320 DEG TO 345 DEG ON MONDAY...THEN BACK TO 330 OR 320 DEG MONDAY NIGHT AS THE HIGH CONTINUES TO BUILD SOUTH. IN ADDITION...IT IS STILL UNCLEAR HOW MUCH EFFECT THE STRONG SUBSIDENCE AND DRYING WILL HAVE ON THE LES. THE NAM AND LOCAL WRF-ARW SUGGEST THAT THIS DRYING WILL HAVE A SIGNIFICANT EFFECT OVER THE WEST...WHICH MAY BE ACCURATE GIVEN THE LESSENED EFFECTIVE OVER WATER FETCH DUE TO THE STRONG WINDS. THESE SAME MODELS ALSO SUGGEST A PRIMARY BAND WITH A LAKE NIPIGON INFLUENCE INTO ALGER COUNTY MONDAY AFTN/MONDAY NIGHT. OVERALL...HAVE INCREASED POPS AND SNOWFALL AMOUNTS COMPARED TO ALL GUIDANCE NUMBERS ON MONDAY INTO MONDAY NIGHT. WITH ALL OF THAT SAID...THE CURRENT THINKING IS THAT MONDAY WILL END UP BEING A FAIRLY WINDY AND SNOWY DAY DOWNWIND OF LAKE SUPERIOR...ESPECIALLY EAST OF MARQUETTE. STILL UNCERTAIN HOW MUCH SNOW WILL NECESSARILY FALL DUE TO THE REASONS GIVEN ABOVE...BUT IT SEEMS REASONABLE TO EXPECT MODERATE SNOWFALL IN ALGER/NRN SCHOOLCRAFT AND LUCE COUNTIES MONDAY INTO TUESDAY. THROWING IN THE STRONG WINDS...WE MAY HAVE OUR FIRST SIGNIFICANT LAKE EFFECT SNOW STORM OF 2013/2014 FOR THESE AREAS. THOUGHT ABOUT ISSUING A WINTER STORM WATCH...BUT OPTED TO HOLD OFF GIVEN THE UNCERTAINTY OF SNOW AMOUNTS. AS FOR AREAS ACROSS THE WEST INTO KEWEENAW...STILL PLENTY OF LAKE INDUCED INSTABILITY BUT THESE AREAS WILL BE ALSO CLOSER TO THE HIGH. WITH THE STRONG WINDS...IT IS POSSIBLE THAT THE KEWEENAW WILL NOT SEE MUCH MORE THAN A FEW INCHES DESPITE FAVORABLE N-NW WINDS. FURTHER SOUTHWEST...AM THINKING THAT THERE WILL BE PERSISTENT SNOW MONDAY INTO MONDAY NIGHT...BUT NOT NECESSARILY ANYTHING HEAVY DUE TO THE LOWER INVERSION HEIGHTS AND MORE DRY AIR. LAKE EFFECT SHOULD START TO DIMINISH ON TUESDAY AS THE SURFACE RIDGE MOVES WELL SOUTH INTO THE SOUTHERN PLAINS...AND HEIGHTS RISE ACROSS THE AREA. BY WEDNESDAY...THE FLOW WILL BECOME MUCH MORE ZONAL ACROSS THE NORTHERN TIER WITH A WARMING TREND TO NEAR OR ABOVE NORMAL BY THURSDAY. THE NEXT SYSTEM IS EXPECTED TO AFFECT THE UPPER GREAT LAKES FRIDAY INTO SATURDAY. THE GFS AND ECMWF ARE VERY DRY WITH THIS SYSTEM...AND FOR NOW WILL GO WITH A DRY FORECAST ALTHOUGH THERE MAY BE A FEW RAIN SHOWERS AROUND WITH THE WEAK FRONTAL PASSAGE FRI AFTN/FRI NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1255 PM EST SAT NOV 9 2013 A LOW PRESSURE SYSTEM TRACKING EAST ACROSS EASTERN LAKE SUPERIOR WILL LEAD TO GUSTY WEST AND THEN NORTHWEST WINDS THROUGH THE PERIOD ALONG WITH LAKE ENHANCED RAIN AND SNOW SHOWERS. WITH PLENTY OF LOW LEVEL MOISTURE AROUND...EXPECT MVFR TO IFR CEILINGS TO PREVAIL FOR MUCH OF THE PERIOD. EXPECT THE WORST CONDITIONS TO OCCUR THIS EVENING INTO THE FIRST PART OF THE OVERNIGHT HOURS OVER THE WEST AS A SURFACE TROUGH BRINGS INCREASING COLD AIR AND SNOW SHOWERS. THINK VISIBILITIES WILL APPROACH IFR VALUES WITH THE STRONGEST SHOWERS AT KIWD/KCMX (ALTHOUGH THERE IS SOME CONCERN OF A RAIN/SNOW MIX AT KCMX). WITH THE NORTHWEST WINDS...KSAW IS LESS FAVORABLE FOR STRONGER SHOWERS AND WILL KEEP CONDITIONS AT MVFR. A HIGH PRESSURE RIDGE BUILDING INTO UPPER MICHIGAN LATE TONIGHT AND SUNDAY WILL LEAD TO A DIMINISHING TREND IN THE SHOWERS AND CLOUDS THROUGH THE MORNING HOURS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 400 PM EST SAT NOV 9 2013 A FAIRLY ACTIVE PERIOD OVER THE UPPER GREAT LAKES OVER THE NEXT COUPLE OF DAYS. A LOW PRESSURE SYSTEM CURRENTLY EXITING EASTERN LAKE SUPERIOR HAS LED TO WEST TO NORTHWESTERLY GALES TO 35KTS OVER PORTIONS OF LAKE SUPERIOR THIS AFTERNOON. EXPECT THESE WINDS TO CONTINUE THROUGH EARLY TOMORROW MORNING OVER EASTERN LAKE SUPERIOR. A HIGH PRESSURE RIDGE WILL QUICKLY MOVE OVER THE WESTERN LAKE LATE TONIGHT AND THE REST OF THE LAKE ON SUNDAY...DIMINISHING THE WINDS BELOW 30KTS. BUT AS THE RIDGE SHIFTS EAST...SOUTHWESTERLY WINDS WILL STAY IN THE 20-30KT RANGE AHEAD OF THE NEXT TROUGH APPROACHING THE AREA. AFTER THE TROUGH MOVES THROUGH SUNDAY NIGHT...ANOTHER PERIOD OF OF NORTHWESTERLY GALES OF 35-40KTS ARE EXPECTED OVER THE CENTRAL/EASTERN LAKE ON MONDAY. THE GALE WATCH THAT WAS ISSUED LAST NIGHT FOR MONDAY AND MONDAY NIGHT WILL CONTINUE. A STRONG HIGH TRAVELLING THROUGH THE CENTRAL PLAINS ON MONDAY NIGHT AND TUESDAY WILL BRING A STRONG RIDGE OVER THE AREA FOR TUESDAY AND DIMINISH WINDS BELOW 25KTS. ONCE AGAIN...WINDS WILL BACK TO THE SOUTHWEST ON WEDNESDAY AHEAD OF ANOTHER TROUGH THAT WILL CROSS THE UPPER GREAT LAKES ON THURSDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM LATE SUNDAY NIGHT THROUGH TUESDAY MORNING FOR LSZ263>267. GALE WARNING UNTIL 1 PM EST SUNDAY FOR LSZ266-267. GALE WARNING UNTIL 10 AM EST SUNDAY FOR LSZ265. GALE WARNING UNTIL 4 AM EST /3 AM CST/ SUNDAY FOR LSZ240>242-263. GALE WARNING UNTIL 11 AM EST SUNDAY FOR LSZ248>251. LAKE MICHIGAN... GALE WARNING FROM 10 PM THIS EVENING TO 7 AM EST SUNDAY FOR LMZ221-248-250. && $$ SHORT TERM...SRF LONG TERM...MRD AVIATION...SRF MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
628 PM CST SUN NOV 10 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 256 PM CST SUN NOV 10 2013 INCREASING CLOUD COVER HALTED THE GOOD WARMING THAT TOOK PLACE THIS MORNING...BUT TEMPERATURES HAVE STILL REACHED NEAR NORMAL LEVELS. AN ARCTIC COLD FRONT LOCATED ALONG INTERSTATE 94 IN NORTH DAKOTA...EXTENDING INTO NORTHWEST MINNESOTA WILL SURGE SOUTH THIS EVENING AND CLEAR THE ENTIRE AREA BY EARLY MONDAY MORNING. TEMPERATURES ARE QUITE COLD ACROSS CANADA WITH HIGHS ONLY IN THE SINGLE DIGITS...BUT EXPECTING THIS COLD AIRMASS TO MODIFY BY 10-15 DEGREES DUE TO LACK OF SNOW COVER ACROSS THE UPPER MIDWEST. GUSTY NORTHWEST WINDS BEHIND THE FRONT WILL BRING WIND CHILLS DOWN INTO THE SINGLE DIGITS AS AIR TEMPERATURES FALL THROUGH THE 20S. SOMETHING TO WATCH IS A NARROW BAND OF LIGHT SNOW ALONG AND JUST BEHIND THE FRONT ACROSS NORTHERN MN AND ND. THIS BAND IS PROGGED TO SLIDE SOUTH WITH THE FRONT ACROSS MAINLY CENTRAL MN AND WRN WI TONIGHT...AND FAR SOUTHERN MN MONDAY MORNING. ONE THING THIS BAND WILL HAVE TO CONTEND WITH IS A LOT OF DRY AIR IN THE BOUNDARY LAYER. AS THE FRONT ACCELERATES SOUTHWARD TONIGHT...THE WINDOW OF OPPORTUNITY WILL NARROW WHEN FORCING COINCIDES WITH NEAR BOUNDARY LAYER SATURATION. THUS...ONLY ANTICIPATING A BRIEF PERIOD OF LIGHT SNOW SHOWERS AT ANY GIVEN LOCATION...IF IT EVEN HAPPENS AT ALL. WILL MAINTAIN MEDIUM POPS ACROSS THE AFOREMENTIONED AREAS LATE TONIGHT AND EARLY MONDAY. A 1045 MB HIGH WILL BUILD INTO THE NORTHERN PLAINS MONDAY WITH STRONG CAA LIMITING ANY RECOVERY FROM TONIGHT/S LOWS. VERY DRY AIR WILL BRING RAPID CLEARING AS PW VALUES OF NEAR A TENTH OF AN INCH ARRIVE MONDAY AFTERNOON. NOT SURPRISINGLY...THESE VALUES WOULD BE NEAR THE RECORD LOW FOR THE MONTH. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 256 PM CST SUN NOV 10 2013 LARGE HIGH PRESSURE AREA WILL DROP SOUTH OVER THE CENTRAL CONUS MONDAY NIGHT AND TUESDAY. THIS WILL PROVIDE SOME COLD OVERNIGHT LOWS INTO TUESDAY. SURFACE FLOW BECOMES MORE SOUTHERLY ON THE BACKSIDE OF THE HIGH TUESDAY NIGHT WITH A WARMING TREND RETURNING TO THE REGION FOR THE REMAINDER OF THE WEEK. THERE IS A SMALL THREAT OF RAIN AND SNOW OVER THE SOUTHEAST CWA THURSDAY INTO THURSDAY NIGHT AS A WEAK SHORT WAVE MOVES ACROSS THE AREA. MOISTURE WILL BE LACKING HOWEVER...AND IF IT OCCURS IT WOULD BE INSIGNIFICANT. LONGER RANGE MODELS CARVE OUT A TROUGH OVER THE WESTERN CONUS INTO NEXT WEEKEND. A LEADING SHORT WAVE IS FORECAST TO LIFT NORTHEAST AND AFFECT THE AREA LATER SATURDAY INTO SUNDAY. AT THE MOMENT...MOST OF THIS WOULD BE IN THE FORM OF RAIN...BUT THERE IS A SMALL CHANCE OF A MIX SATURDAY MORNING...IF THE MOISTURE ARRIVES EARLY ENOUGH. LATER IN THE PERIOD...THE NAO TELECONNECTION IS TRENDING STRONGLY NEGATIVE ONCE AGAIN. THIS WOULD CONFIRM THE SIGNAL THE LONGER TERM MODELS ARE PRESENTLY SHOWING...WITH A SIGNIFICANT STORM POSSIBLY AFFECTING THE AREA NEXT WEEK...FOLLOWED BY MUCH COLDER AIR. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 628 PM CST SUN NOV 10 2013 ARCTIC FRONT CONTINUES MOVING IN...WITH A NARROW AREA OF MVFR CEILINGS EVIDENT IN NORTH DAKOTA OBSERVATIONS...AS FAR WEST AS JAMESTOWN. SOME BRIEF SNOW SHOWERS ALSO IN SOME OBS INCLUDING FARGO BETWEEN 23Z-00Z. LATEST RAP LATCHES ON TO THIS...AND THERE IS SOME HINT OF THIS AS SEEN IN BUFKIT AND IN THE LAMP GUIDANCE. HAVE ADDED MVFR CEILINGS LATE EVENING OR OVERNIGHT FOR 2-4 HOURS AT MOST SITES PLUS SOME SNOW SHOWERS. GUSTY NORTH WINDS WILL ALSO ARRIVE WITH THE FRONT. AIR MASS DRIES OUT SIGNIFICANTLY AND CLEAR SKIES SHOULD BE WIDESPREAD BY LATE MORNING. KMSP...TWO MAIN CONCERNS AND/OR CHANGES. ADDED SOME SHORT-LIVED MVFR CEILING WITH FLURRIES AROUND 06Z...AND ALSO SLIGHTLY ADJUSTED THE TIMING OF THE WIND SHIFTS. NARROW SWATH OF MVFR CEILINGS EXTENDS INTO SOUTHEASTERN NORTH DAKOTA AS OF 00Z...AND THIS DOES LOOK TO MOVE SOUTHEAST ACROSS KMSP WITH FRONT. MAY BE SOME FLURRIES BRINGING VSBY DOWN TO 4SM AT BRIEF TIMES. AS FOR WIND...LEADING TROUGH WILL BRING WIND TO THE W OR NW LATE THIS EVENING BUT INCOMING SURGE OF COLD AIR AND NNW WINDS WITH GUSTS OVER 20 KNOTS WILL ARRIVE A COUPLE HOURS AFTER THE WNW WIND SHIFT. CLEARING SKIES BY 18Z BUT GUSTS SHOULD REMAIN AROUND 20 KNOTS THROUGH THE AFTERNOON WITH INCOMING ARCTIC AIR. /OUTLOOK FOR KMSP/ TUE...VFR. W WINDS 5-10 KTS. WED...VFR. SW WINDS 15 KTS. THU...VFR. WINDS VRB 5 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...BORGHOFF LONG TERM...DWE AVIATION...TDK
AREA FORECAST DISCUSSION
NWS JACKSON MS
1035 AM CST SAT NOV 9 2013 .UPDATE... THE FORECAST IS GENERALLY ON TRACK WITH A FEW ADJUSTMENTS MADE TO TEMPERATURE/DEWPOINT FORECASTS FOR THE REMAINDER OF TODAY INTO THIS EVENING. MORNING SOUNDINGS REVEAL THE VERY DRY SUB-CLOUD LAYER THAT IS LIMITING RAIN FROM REACHING THE GROUND AND THE LOW POPS FOR LIGHT RAIN AND SPRINKLES STILL LOOK GOOD. TEMPERATURES HAVE BEEN WARMING A LITTLE FASTER AS SOLID ALTOSTRATUS EXITS AND IS REPLACED BY A MORE BROKEN ALTOCUMULUS DECK ASSOCIATED WITH THE WEAK SHORTWAVE TROUGH. THE BREAKS IN THE CLOUDS SHOULD ALLOW FOR SLIGHTLY MORE WARMING AND HAVE RAISED TEMPERATURES A FEW DEGREES. OTHERWISE...NEW GLOBAL MODEL GUIDANCE STILL INDICATES A BIG COOL DOWN FOR THE MIDDLE OF THE UPCOMING WEEK. /EC/ && .AVIATION... VFR CONDS AND LGT SFC WINDS TO PREVAIL OVR THE NEXT 24 HRS. OCSNL -RA/DZ NOT OUT OF THE QUESTION N OF I-20 THIS AFTN AND EVENING. /BK/ && .PREV DISCUSSION... /ISSUED 335 AM CST SAT NOV 9 2013/ ..UNSEASONABLY COOL WEATHER WITH FIRST WIDESPREAD FREEZE EXPECTED MIDDLE OF NEXT WEEK... SHORT TERM...TODAY THROUGH SUNDAY NIGHT...MAIN CONCERN IN SHORT TERM IS CLOUDS/PRECIP FIRST 24 HOURS. IR IMAGERY THIS MORNING SHOWS COOLING TOPS OVER ARKLATEX REGION IN RIGHT ENTRANCE REGION OF UPPER JET OVER LOWER LAKES/OHIO VALLEY. RADAR SHOWS AN EXPANDING AREA OF DECENT REFLECTIVITY WITH THIS AREA AS WELL...BUT DUE TO DRY SUBCLOUD LAYER SURFACE OBSERVATIONS INDICATE MUCH OF THE RADAR RETURN IS VIRGA WITH ONLY SOME SPOTTY VERY LIGHT PRECIPITATION BEING REPORTED. 300/305K ISENTROPIC SURFACES INDICATE THAT BEST OVERLAY OF MID/UPPER LEVEL MOISTURE AND WEAK ASCENT WILL BE FOCUSED ACROSS NORTHERN AREAS TODAY AND THIS IS WHERE BEST CHANCE FOR ANY PRECIP SHOULD RESIDE. WHILE BUFR SOUNDINGS INDICATE THAT ATMOSPHERE BELOW ABOUT 750 MB WILL REMAIN QUITE DRY...RECENT TRENDS IN RADAR AS WELL AS REFLECTIVITY FORECASTS FROM HRRR AND HIGH RES WRF RUNS IMPLY ROBUST ENOUGH MID LEVEL PRECIP FOR SOME RAIN TO POSSIBLY GET THROUGH THE DRY LOW LEVELS TO THE SURFACE. THUS WILL ACCEPT THE 20/30 POPS FROM GFS MOS ACROSS NORTHERN AREAS...AND MENTION SPRINKLES ACROSS THE CENTRAL SECTIONS. WIDESPREAD CLOUDS AND GENERALLY NEUTRAL TEMPERATURE ADVECTION WOULD IMPLY DIURNAL WARMING WILL NOT BE TREMENDOUS TODAY MOST AREAS TODAY...AND HAVE WENT NEAR GFS MOS IN ONLY SHOWING 10-15 DEGREE RISE FROM CURRENT READINGS. MORE OF A DIURNAL RANGE EXPECTED IN SE AREAS WHERE TEMPS HAVE FALLEN INTO LOWER 40S...AND SOME SUNSHINE SHOULD ALLOW A MORE ROBUST TEMPERATURE RISE TODAY. TONIGHT 300/305K ISENTROPIC SURFACE MODEL FORECASTS SHOW AXIS OF MOISTURE AND WEAK ASCENT SHIFTING SOUTH ACROSS FORECAST AREA. ASCENT WILL BE WEAKENING AND MOISTURE THINNING OUT WITH SOUTHWARD PROGRESS...BUT GIVEN REFLECTIVITY FORECASTS FROM HIGH RES AND LOCAL WRF MODELS HARD TO ARGUE AGAINST KEEPING A LOW POP IN NORTHERN AND CENTRAL AREAS PER GFS MOS. MODELS SHOW MOISTURE/CLOUDS BEGINNING TO DECREASE LATE TONIGHT FROM THE W/NW WHICH COMBINED WITH GENERALLY LIGHT WINDS COULD ALLOW SOME BETTER RADIATIONAL COOLING. SHOULD ALSO BESOME INCREASE IN LOW LEVEL COLD ADVECTION AS INITIAL SURGE OF HIGH PRESSURE MOVES INTO THE MIDWEST...THUS WILL STICK WITH CURRENT FORECAST MINS IN THE MID TO UPPER 40S. SUNDAY LOOKS TO BE A NICER DAY WITH MUCH MORE SUNSHINE AND TEMPS WARMING INTO THE 70S. LIGHT WINDS AND LOW DEWPOINTS ALONG WITH PARTLY CLOUDY SKIES SHOULD ALLOW FOR A DECENT RADIATIONAL COOLING NIGHT SUNDAY NIGHT. GUIDANCE TEMPS SEEM REASONABLE THROUGH THIS PERIOD. LONG TERM...MONDAY THROUGH SATURDAY...A DEFINITE COOL DOWN LOOKS ON TAP FOR THE AREA IN THE EXTENDED. HIGH PRESSURE WILL PREVAIL ACROSS THE ARKLAMISS ON MONDAY WITH WARM TEMPERATURES IN THE LOW TO MID 70S. A STRONG COLD FRONT WILL APPROACH THE AREA MONDAY NIGHT AND MOVE INTO THE DELTA EARLY ON TUESDAY. THE FRONT WILL BE MAINLY DRY AS THERE WILL BE LITTLE MOISTURE TO WORK WITH...BUT THERE COULD BE A FEW LIGHT RAINSHOWERS TUESDAY AFTERNOON. THE SURFACE PRESSURE GRADIENT WILL BE VERY TIGHT BEHIND THE BOUNDARY SO EXPECT SOME PRETTY GUSTY NORTHERLY WINDS ON TUESDAY. TEMPERATURES WILL FALL THROUGH THE EVENING HOURS UNDER STRONG COLD AIR ADVECTION. BOTH THE GFS/ECMWF INDICATE COLD TEMPERATURES ACROSS THE AREA TUESDAY NIGHT WITH THE ECMWF H925 TEMPERATURES FALLING TO -4 TO -6C WITH THE GFS SLIGHTLY WARMER. THE WINDS WILL REMAIN BREEZY OVERNIGHT ..BUT EXPECT LOWS TO STILL FALL INTO THE MID/UPPER 20S ACROSS MUCH OF THE AREA. A COOL DAY IS ON TAP FOR WEDNESDAY AS H925 TEMPS RANGE FROM 0 TO -2C. HIGHS WILL ONLY CLIMB INTO THE UPPER 40S TO NEAR 50. ANOTHER COLD NIGHT IS ON TAP WEDNESDAY NIGHT AS THE SURFACE HIGH MOVES OVER THE REGION AND WITH LIGHT WINDS...STRONG RADIATIONAL COOLING WILL TAKE PLACE WITH LOWS FALLING INTO THE MID/UPPER 20S. THE SURFACE HIGH WILL SHIFT TO THE EAST ON THURSDAY AND THIS WILL ALLOW FOR EAST TO SOUTHEAST FLOW AND WARMER H925/H850 TEMPERATURES WITH HIGHS IN THE UPPER 50S TO NEAR 60. SURFACE RIDGING WILL CONTINUE TO PREVAIL ON FRIDAY WITH THE WARMING TREND CONTINUING UNDER SOUTHEASTERLY FLOW. MOISTURE WILL INCREASE ACROSS THE AREA FRIDAY NIGHT AND SATURDAY AND THIS COMBINED WITH SHORT WAVES MOVING ACROSS THE REGION WILL INCREASE THE CHANCE FOR SHOWERS OR THUNDERSTORMS DURING THIS PERIOD. STUCK PRETTY CLOSE TO GUIDANCE POPS/TEMPS THROUGH MOST OF THE PERIOD...BUT DID CUT BELOW GUIDANCE HIGHS ON WEDNESDAY AND ALSO BELOW GUIDANCE LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT IN THE USUAL COOLER LOCATIONS./15/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 64 47 73 44 / 13 20 4 8 MERIDIAN 67 45 73 42 / 10 21 5 7 VICKSBURG 64 47 73 43 / 17 19 4 7 HATTIESBURG 71 49 75 46 / 4 11 8 9 NATCHEZ 67 47 73 46 / 10 13 4 7 GREENVILLE 61 45 68 43 / 26 25 3 6 GREENWOOD 62 44 69 42 / 20 26 4 6 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON MS
335 AM CST SAT NOV 9 2013 ...UNSEASONABLY COOL WEATHER WITH FIRST WIDESPREAD FREEZE EXPECTED MIDDLE OF NEXT WEEK... .SHORT TERM...TODAY THROUGH SUNDAY NIGHT...MAIN CONCERN IN SHORT TERM IS CLOUDS/PRECIP FIRST 24 HOURS. IR IMAGERY THIS MORNING SHOWS COOLING TOPS OVER ARKLATEX REGION IN RIGHT ENTRANCE REGION OF UPPER JET OVER LOWER LAKES/OHIO VALLEY. RADAR SHOWS AN EXPANDING AREA OF DECENT REFLECTIVITY WITH THIS AREA AS WELL...BUT DUE TO DRY SUBCLOUD LAYER SURFACE OBSERVATIONS INDICATE MUCH OF THE RADAR RETURN IS VIRGA WITH ONLY SOME SPOTTY VERY LIGHT PRECIPITATION BEING REPORTED. 300/305K ISENTROPIC SURFACES INDICATE THAT BEST OVERLAY OF MID/UPPER LEVEL MOISTURE AND WEAK ASCENT WILL BE FOCUSED ACROSS NORTHERN AREAS TODAY AND THIS IS WHERE BEST CHANCE FOR ANY PRECIP SHOULD RESIDE. WHILE BUFR SOUNDINGS INDICATE THAT ATMOSPHERE BELOW ABOUT 750 MB WILL REMAIN QUITE DRY...RECENT TRENDS IN RADAR AS WELL AS REFLECTIVITY FORECASTS FROM HRRR AND HIGH RES WRF RUNS IMPLY ROBUST ENOUGH MID LEVEL PRECIP FOR SOME RAIN TO POSSIBLY GET THROUGH THE DRY LOW LEVELS TO THE SURFACE. THUS WILL ACCEPT THE 20/30 POPS FROM GFS MOS ACROSS NORTHERN AREAS...AND MENTION SPRINKLES ACROSS THE CENTRAL SECTIONS. WIDESPREAD CLOUDS AND GENERALLY NEUTRAL TEMPERATURE ADVECTION WOULD IMPLY DIURNAL WARMING WILL NOT BE TREMENDOUS TODAY MOST AREAS TODAY...AND HAVE WENT NEAR GFS MOS IN ONLY SHOWING 10-15 DEGREE RISE FROM CURRENT READINGS. MORE OF A DIURNAL RANGE EXPECTED IN SE AREAS WHERE TEMPS HAVE FALLEN INTO LOWER 40S...AND SOME SUNSHINE SHOULD ALLOW A MORE ROBUST TEMPERATURE RISE TODAY. TONIGHT 300/305K ISENTROPIC SURFACE MODEL FORECASTS SHOW AXIS OF MOISTURE AND WEAK ASCENT SHIFTING SOUTH ACROSS FORECAST AREA. ASCENT WILL BE WEAKENING AND MOISTURE THINNING OUT WITH SOUTHWARD PROGRESS...BUT GIVEN REFLECTIVITY FORECASTS FROM HIGH RES AND LOCAL WRF MODELS HARD TO ARGUE AGAINST KEEPING A LOW POP IN NORTHERN AND CENTRAL AREAS PER GFS MOS. MODELS SHOW MOISTURE/CLOUDS BEGINNING TO DECREASE LATE TONIGHT FROM THE W/NW WHICH COMBINED WITH GENERALLY LIGHT WINDS COULD ALLOW SOME BETTER RADIATIONAL COOLING. SHOULD ALSO BESOME INCREASE IN LOW LEVEL COLD ADVECTION AS INITIAL SURGE OF HIGH PRESSURE MOVES INTO THE MIDWEST...THUS WILL STICK WITH CURRENT FORECAST MINS IN THE MID TO UPPER 40S. SUNDAY LOOKS TO BE A NICER DAY WITH MUCH MORE SUNSHINE AND TEMPS WARMING INTO THE 70S. LIGHT WINDS AND LOW DEWPOINTS ALONG WITH PARTLY CLOUDY SKIES SHOULD ALLOW FOR A DECENT RADIATIONAL COOLING NIGHT SUNDAY NIGHT. GUIDANCE TEMPS SEEM REASONABLE THROUGH THIS PERIOD. .LONG TERM...MONDAY THROUGH SATURDAY...A DEFINITE COOL DOWN LOOKS ON TAP FOR THE AREA IN THE EXTENDED. HIGH PRESSURE WILL PREVAIL ACROSS THE ARKLAMISS ON MONDAY WITH WARM TEMPERATURES IN THE LOW TO MID 70S. A STRONG COLD FRONT WILL APPROACH THE AREA MONDAY NIGHT AND MOVE INTO THE DELTA EARLY ON TUESDAY. THE FRONT WILL BE MAINLY DRY AS THERE WILL BE LITTLE MOISTURE TO WORK WITH...BUT THERE COULD BE A FEW LIGHT RAINSHOWERS TUESDAY AFTERNOON. THE SURFACE PRESSURE GRADIENT WILL BE VERY TIGHT BEHIND THE BOUNDARY SO EXPECT SOME PRETTY GUSTY NORTHERLY WINDS ON TUESDAY. TEMPERATURES WILL FALL THROUGH THE EVENING HOURS UNDER STRONG COLD AIR ADVECTION. BOTH THE GFS/ECMWF INDICATE COLD TEMPERATURES ACROSS THE AREA TUESDAY NIGHT WITH THE ECMWF H925 TEMPERATURES FALLING TO -4 TO -6C WITH THE GFS SLIGHTLY WARMER. THE WINDS WILL REMAIN BREEZY OVERNIGHT ...BUT EXPECT LOWS TO STILL FALL INTO THE MID/UPPER 20S ACROSS MUCH OF THE AREA. A COOL DAY IS ON TAP FOR WEDNESDAY AS H925 TEMPS RANGE FROM 0 TO -2C. HIGHS WILL ONLY CLIMB INTO THE UPPER 40S TO NEAR 50. ANOTHER COLD NIGHT IS ON TAP WEDNESDAY NIGHT AS THE SURFACE HIGH MOVES OVER THE REGION AND WITH LIGHT WINDS...STRONG RADIATIONAL COOLING WILL TAKE PLACE WITH LOWS FALLING INTO THE MID/UPPER 20S. THE SURFACE HIGH WILL SHIFT TO THE EAST ON THURSDAY AND THIS WILL ALLOW FOR EAST TO SOUTHEAST FLOW AND WARMER H925/H850 TEMPERATURES WITH HIGHS IN THE UPPER 50S TO NEAR 60. SURFACE RIDGING WILL CONTINUE TO PREVAIL ON FRIDAY WITH THE WARMING TREND CONTINUING UNDER SOUTHEASTERLY FLOW. MOISTURE WILL INCREASE ACROSS THE AREA FRIDAY NIGHT AND SATURDAY AND THIS COMBINED WITH SHORT WAVES MOVING ACROSS THE REGION WILL INCREASE THE CHANCE FOR SHOWERS OR THUNDERSTORMS DURING THIS PERIOD. STUCK PRETTY CLOSE TO GUIDANCE POPS/TEMPS THROUGH MOST OF THE PERIOD...BUT DID CUT BELOW GUIDANCE HIGHS ON WEDNESDAY AND ALSO BELOW GUIDANCE LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT IN THE USUAL COOLER LOCATIONS./15/ && .AVIATION... VFR CONDITIONS SHOULD PREDOMINATE NEXT 24 HOURS AS ONLY MID/HIGH LEVEL CLOUDS ARE ANTICIPATED. SOME LIGHT PRECIPITATION COULD OCCUR AT TIMES...BUT GIVEN DRY LOWER LEVELS EXPECT THAT LITTLE IN THE WAY OF VSBY RESTRICTIONS SHOULD OCCUR. WINDS WILL BE LIGHT. /AEG/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 63 47 73 44 / 13 20 4 8 MERIDIAN 66 45 73 42 / 10 21 5 7 VICKSBURG 65 47 73 43 / 17 19 4 7 HATTIESBURG 72 49 75 46 / 4 11 8 9 NATCHEZ 68 47 73 46 / 10 13 4 7 GREENVILLE 60 45 68 43 / 26 25 3 6 GREENWOOD 60 44 69 42 / 20 26 4 6 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ AEG/15
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
347 PM CST SAT NOV 9 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 347 PM CST SAT NOV 9 2013 CHALLENGES INCLUDE LOW END POPS THIS EVENING AND THEN CLOUD/ TEMPERATURE TRENDS THROUGH THE PERIOD. GFS/NAM/ECMWF/GEM ARE IN GOOD OVERALL AGREEMENT AND WILL USE A BLENDED SOLUTION FOR THIS FORECAST PACKAGE. WILL KEEP WIND ADVISORY IN PLACE UNTIL 00 UTC WITH A FEW OBSERVATION SITES IN THE HIGHER ELEVATIONS WEST OF THE VALLEY STILL NEAR 30 MPH SUSTAINED WITH HIGHER GUSTS. EVENING SHIFT MAY BE ABLE TO CANCEL EARLY. FOR TONIGHT...LOW CLOUDS WILL BE SLOW TO MOVE OUT OF THE FORECAST AREA WITH THE RAP 925 HPA RH SUGGESTING THE CLEARING LINE WILL REACH THE VALLEY FLOOR BY 09 TO 12 UTC SUNDAY. THE LAKE OF THE WOODS REGION WILL REMAIN CLOUDY OVERNIGHT AND EXPECT TEMPERATURES HERE TO ONLY DROP INTO THE MID 20S. ASSSUMING SOME DEGREE OF CLEARING TAKES PLACE ELSEWHERE...ALL OTHER AREAS SHOULD DROP INTO THE TEENS. WEAK SNOW SHOWERS/DRIZZLE ACROSS NORTHWEST MN SHOULD EXIT THE FORECAST AREA BY 03 UTC WITH DRY CONDITIONS THEREAFTER. A STRONG COLD FRONT WILL DROP ACROSS THE REGION SUNDAY AFTERNOON AND EVENING WITH THE THREAT FOR SCATTED SNOW SHOWERS ALONG AND AHEAD OF ITS PASSAGE. BEST CHANCE FOR PRECIPITATION WILL BE ACROSS NORTHWEST MN...BUT QPF WILL BE LIGHT AND ANY SNOW ACCUMULATION WILL BE A HALF INCH OR LESS. FRONTAL PASSAGE SHOULD BE LATE ENOUGH IN THE DAY FOR TEMPERATURES TO RISE INTO THE MID 30S TO AS HIGH AS THE LOWER 40S ACROSS THE SOUTH IF THE SUN MAKES A PROLONGED APPEARANCE. EXPECT CLEARING SKIES FROM NORTH TO SOUTH SUNDAY NIGHT IN THE WAKE OF THE FRONT WITH RAPIDLY DROPPING TEMPERATURES. NORTH WIND FROM 10 TO 15 MPH WILL KEEP TEMPERATURES FROM BOTTOMING OUT...BUT STILL EXPECT WIDESPREAD LOW TO MID TEENS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 347 PM CST SAT NOV 9 2013 MONDAY AND TUESDAY WILL BE DRY AS A 1044 TO 1048 HPA SURFACE HIGH DROPS SOUTH FROM CANADA AND INTO THE CENTRAL PLAINS. CENTER OF HIGH REMAINS PRIMARILY SOUTH AND WEST OF THE FORECAST AREA LIMITING THE EXTENT TO WHICH WINDS WILL BECOME CALM. ASSUMING CLEAR SKIES...THIS WILL ALSO LIMIT NOCTURNAL COOLING...BUT WITH 925 HPA TEMPERATURES STILL FROM -8 TO -12 C...TUESDAY MORNING LOWS WILL DROP INTO THE SINGLE DIGITS ABOVE ZERO. BY FAR THE COLDEST AIR MASS OF THE SEASON AND WOULDN/T BE SURPRISED TO SEE A FEW SUB- ZERO READINGS. HIGHS MONDAY WILL ONLY BE IN THE MID TEENS TO LOW 20S WITH A NOTICEABLE WARM-UP INTO TUESDAY WITH HIGHS FROM THE MID 20S TO LOWER 30S. TUESDAY NIGHT THROUGH SATURDAY...MAJOR GUIDANCE IN AGREEMENT WITH UPPER RIDGE AND THERMAL RIDGE AXIS OVER THE FORECAST AREA AS THE EXTENDED PERIOD BEGINS WEDNESDAY. WITH FAVORABLE WEST WINDS...TEMPS SHOULD RISE INTO THE 40S ACROSS MOST AREAS. BEYOND WEDNESDAY...FLOW TRANSITIONS TO NORTHWEST WITH A MORE PRONOUNCED SHORT WAVE MOVING THROUGH AT SOME POINT THURSDAY INTO FRIDAY. ATMOSPHERIC PROFILES POINT TOWARD A RAIN SNOW MIXTURE DURING THE DAYLIGHT HOURS WITH SNOW AT NIGHT. ANOTHER SYSTEM WILL BRING A CHANCE FOR PCPN TO THE NORTHERN AREAS LATER SATURDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 111 PM CST SAT NOV 9 2013 VFR CIGS AT KFAR SHOULD TRANSITION TO MVFR AS LOWER CLOUDS STREAM DOWN VIA NORTHWEST FLOW FROM DEVILS LAKE BASIN. SNOW SHOWERS WILL LINGER FROM KTVF THROUGH KBJI FOR A FEW MORE HOURS. ALL LOCATIONS SHOULD LOSE THEIR CIGS BY 06Z TONIGHT. SUSTAINED WIND CORE AOA 25KTS KDVL TO CONTINUE THROUGH LATE AFTERNOON DESPITE CLOUD COVER...WHILE THE OTHER SITES STAY CLOSER TO 20 KTS. DECREASE TO 10 KTS OR LESS EXPECTED THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ006-014-015-024- 026-028-029-038-039-049-052-053. MN...NONE. && $$ SHORT TERM...ROGERS LONG TERM...ROGERS/WJB AVIATION...WJB
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
111 PM CST SAT NOV 9 2013 .UPDATE... ISSUED AT 111 PM CST SAT NOV 9 2013 WIND ADVISORY IN GOOD SHAPE...ALTHOUGH OBSERVED SPEEDS ARE MARGINAL. AREAS FROM DEVILS LAKE TO COOPERSTOWN TO VALLEY CITY HAVE HOVERED AROUND 25 TO 28 KTS SUSTAINED WITH LESSER WINDS FARTHER EAST. WILL NOT EXPAND CURRENT HEADLINE...BUT MAY BE ABLE TO CANCEL PORTIONS OF IT EARLY WITH THE 4 PM FORECAST ISSUANCE. SOME BREAKS IN THE CLOUDS ALSO FORMING ACROSS SOUTHEAST ND...BUT MOSTLY CLOUDY CONDITIONS SHOULD PERSIST THROUGH THE AFTERNOON. TEMPERATURES ON TRACK WITH MINIMAL MOVEMENT SINCE MORNING UPDATE. REGIONAL RADAR SHOWING WEAK BAND OF LIGHT SNOW JUST EAST OF THE RED RIVER AND THIS WILL CONTINUE TO PROGRESS INTO NORTHWEST MN WITH MINIMAL ACCUMULATION...IF ANY. FORECAST IN GOOD SHAPE WITH NO MAJOR CHANGES AT THIS TIME. UPDATE ISSUED AT 1014 AM CST SAT NOV 9 2013 MAIN CHALLENGE FOR THE MORNING UPDATE IS WIND. SURFACE OBSERVATIONS FROM RUGBY TO CARRINGTON HAVE ALREADY EXCEEDED A SUSTAINED 26 KTS (30 MPH) WITH A GUST TO 51 MPH AT CARRINGTON. EVEN FARGO HAD A PEAK WIND TO 43 MPH AT 0830 CST. WITH THE RAP SHOWING AT LEAST 35 KTS AT 925 HPA TO MIX TO THE SURFACE AND UP TO 40 KTS AT 850 HPA IF THE BOUNDARY LAYER CAN DEEPEN THAT FAR WITH CLOUD COVER...THINK A WIND ADVISORY IS PRUDENT FOR SOUTHEAST ND INTO THE DEVILS LAKE BASIN UNTIL 00 UTC TONIGHT. TRUE ADVISORY CRITERIA MAY NOT BE MET AT ALL LOCATIONS AND BE INTERMITTENT...BUT EXPECT NORTHWEST WIND BETWEEN 25 AND 35 MPH WITH GUSTS UP TO 45 MPH. SCATTERED SNOW SHOWERS WILL BE CONFINED MAINLY TO NORTHWEST MN THROUGH THE DAY. WEB CAMS IN THIS AREA SUGGEST REDUCTIONS IN VISIBILITY INTO THE 2 TO 5 SM RANGE ARE DUE MORE TO PATCHY FOG AND DRIZZLE THAN SNOW...SO ADDED FOG THROUGH 18 UTC AND DRIZZLE THROUGH 00 UTC. SURFACE TEMPERATURES SHOULD REMAIN STEADY AT OR SLIGHTLY ABOVE FREEZING...SO THERE MAY BE SOME SLICK SPOTS...BUT DO NOT ANTICIPATE MUCH IF ANY ADDITIONAL SNOW ACCUMULATION OR DRIZZLE FREEZING ON IMPACT. REST OF THE FORECAST IN GOOD SHAPE WITH NO MAJOR CHANGES AT THIS TIME. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 322 AM CST SAT NOV 9 2013 THE MAIN CONCERN FOR TODAY WILL BE WIND SPEEDS. LOW PRESSURE IS PROPAGATING EASTWARD...LEAVING THE REGION IN A WEAK COLD AIR ADVECTION REGIME. MODELS INDICATE UNIDIRECTIONAL FLOW TO 925MB BY LATE MORNING ACROSS MUCH OF THE FA...AND UP TO 850MB ACROSS SOUTHEAST NORTH DAKOTA. MODELS INDICATE 925MB WIND SPEEDS 30-35 KNOTS...AND 850MB WIND SPEEDS AROUND 40 KNOTS (WEAKER ACROSS THE NORTHERN FA). WITH THE MODELS INDICATING DEEPER MIXING ACROSS SOUTHEAST NORTH DAKOTA...THIS AREA WILL BE VERY CLOSE TO WIND ADVISORY CRITERIA (MOS GUIDANCE INDICATES AROUND 26 KNOTS SUSTAINED). CLOUDS ARE EXPECTED TO REMAIN THROUGH MUCH OF THE DAY...WHICH COULD LIMIT MIXING POTENTIAL...AND WILL HOLD OFF ON AN ADVISORY. OTHERWISE...SATELLITE IMAGERY INDICATES CLOUDS UPSTREAM...AND UNTIL THE SURFACE RIDGE MOVES THROUGH THE REGION TONIGHT...DO NOT SEE ANY POTENTIAL FOR CLEARING (DELAYED THE CLEARING UNTIL TONIGHT). TEMPERATURES WILL START OUT WARM TODAY...BUT WILL LIKELY ONLY RISE A FEW DEGREES. A STRONGER UPPER WAVE IS ENTERING SOUTHERN MANITOBA...AND WILL BRING SNOW SHOWERS TO NORTHWEST MINNESOTA TODAY. NOT MUCH ACCUMULATION EXPECTED...BUT COULD BE UP TO AN INCH. FLURRIES POSSIBLE ELSEWHERE GIVEN CAA AND LOW CLOUDS IN PLACE. LOW LEVEL RIDGE MOVING THROUGH THE REGION TONIGHT SHOULD BE ABLE TO CLEAR THE SKY. ASSUMING THAT THE SKY DOES CLEAR...TEMPERATURES WILL BE IN THE TEENS (FOLLOWING COLDER GUIDANCE WHICH HAS VERIFIED BETTER THE PAST WEEK). ON SUNDAY...MAX TEMPERATURES WILL BE DETERMINED BY THE TIMING OF A STRONG COLD FRONT. MOST MODELS INDICATE THIS FEATURE WILL MOVE THROUGH THE REGION DURING THE AFTERNOON HOURS...WHICH SHOULD PROVIDE MOST AREAS ENOUGH TIME TO WARM INTO THE UPPER 30S OR LOW- MID 40S (ESPECIALLY RIGHT AHEAD OF THE COLD FRONT WHERE LOW LEVEL FLOW WILL BE WESTERLY). STAYED CONSERVATIVE WITH THE MAX TEMP FORECAST...ALTHOUGH OUR FORECAST COULD BE 5F-8F TOO COOL. THE STRONGEST SYNOPTIC FORCING WILL BE ACROSS NORTHWEST MINNESOTA...CLOSER TO THE UPPER WAVE...AND WE HAVE LOWER END POPS HERE. ALSO...INCREASED WIND SPEEDS BEHIND THE FROPA GIVEN THE STRONG COLD AIR ADVECTION EXPECTED (MODELS ONLY SHOWING WINDS ALOFT OF 25-30 KNOTS...SO IF THAT IS TRUE THIS WOULD BE SHORT OF ADVISORY CRITERIA...JUST A BRIEF PERIOD OF GUSTY WINDS). .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 322 AM CST SAT NOV 9 2013 SUNDAY NIGHT-MONDAY NIGHT...STRONG COLD FRONT WILL CONTINUE TO SWEEP THROUGH THE REGION SUNDAY NIGHT...WITH HIGH PRESSURE FOLLOWING FOR MONDAY INTO MONDAY NIGHT. MODELS DIFFER A LITTLE BIT WITH 850MB TEMPERATURE VALUES ON MONDAY...BUT GENERALLY -12C TO -18C. NEEDLESS TO SAY...TEMPERATURES WILL BE WELL BELOW NORMAL VALUES. FOLLOWED THE COLDER GUIDANCE CONSIDERING MODEL PERFORMANCE FOR THIS PAST WEEK. TUESDAY-FRIDAY...TRANSITORY MID/UPPER RIDGING WILL SLIDE ACROSS THE AREA ON TUESDAY AS THE SFC HIGH CONTINUES SOUTHWARD ACROSS THE PLAINS. INCREASING WARM ADVECTION AND SOUTHWEST SFC WINDS SHOULD ALLOW FOR SOME DECENT TEMP RECOVERY...LIMITED SOMEWHAT THOUGH BY THE VERY CHILLY START TO THE DAY...KEEPING HIGH TEMPS A BIT BELOW NORMAL. TUESDAY NIGHT WILL NOT BE AS COLD...WITH CONTINUED WARM ADVECTION AND A STRENGTHENING PRESSURE GRADIENT KEEPING WINDS UP. THE THERMAL RIDGE AXIS WILL MOVE ACROSS THE AREA ON WEDNESDAY AS A RELATIVELY WEAK COLD FRONT ADVANCES TOWARDS THE REGION. WITH FAVORABLE WEST WINDS...TEMPS INTO THE 40S IN SOME AREAS CAN BE EXPECTED. BEYOND WEDNESDAY...MODELS SHOW SOME DEGREE OF NORTHWEST FLOW ALOFT DEVELOPING FOR THE LATTER HALF OF THE WEEK. ALTHOUGH THE TIMING AND PLACEMENT VARY AMONG MODELS...SEVERAL WEAK SHORTWAVE TROUGHS WILL LIKELY PASS THROUGH THE REGION LATE IN THE WEEK. ANY IMPULSE MAY GENERATE LIGHT PRECIP...BUT NO MAJOR SYSTEMS ARE EXPECTED. TEMPS LOOK TO REMAIN SEASONABLE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 111 PM CST SAT NOV 9 2013 VFR CIGS AT KFAR SHOULD TRANSITION TO MVFR AS LOWER CLOUDS STREAM DOWN VIA NORTHWEST FLOW FROM DEVILS LAKE BASIN. SNOW SHOWERS WILL LINGER FROM KTVF THROUGH KBJI FOR A FEW MORE HOURS. ALL LOCATIONS SHOULD LOSE THEIR CIGS BY 06Z TONIGHT. SUSTAINED WIND CORE AOA 25KTS KDVL TO CONTINUE THROUGH LATE AFTERNOON DESPITE CLOUD COVER...WHILE THE OTHER SITES STAY CLOSER TO 20 KTS. DECREASE TO 10 KTS OR LESS EXPECTED THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ006-014-015-024- 026-028-029-038-039-049-052-053. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...TG LONG TERM...TG/MAKOWSKI AVIATION...WJB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1204 PM CST SAT NOV 9 2013 .UPDATE... ISSUED AT 1203 PM CST SAT NOV 9 2013 LATEST FOG/STRATUS LOOP SHOWS EROSION TAKING PLACE IN FAR SOUTHWEST AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA. EXPECT THIS TO CONTINUE THROUGH THE AFTERNOON WITH THE EAST CENTRAL AND JAMES RIVE VALLEY MAINTAINING BKN/OVC CONDITIONS. WIND ADVISORY CONTINUES WITH UPDATES TO THE SKY GRIDS AND WINDS THIS PERIOD. UPDATE ISSUED AT 924 AM CST SAT NOV 9 2013 CARRINGTON HAD A GUST TO 51 MPH...WITH WIND 30 MPH SUSTAINED AT MINOT AND RUGBY. A WIND ADVISORY HAS BEEN ISSUED FOR NORTH CENTRAL AND EAST CENTRAL NORTH DAKOTA THROUGH 00Z SUNDAY AS THE STRONG WINDS WILL SPREAD SOUTH THROUGH THE AFTERNOON. UPDATES FORTHCOMING TO REST OF TEXT PRODUCTS. UPDATE ISSUED AT 821 AM CST SAT NOV 9 2013 LATEST FOG/STRATUS SATELLITE IMAGERY SHOWS A SWATH OF LOW CLOUDS WITH MULTIPLE BREAKS SOUTH OF INTERSTATE 94...WITH LESS BREAKS NORTH. USING A BLEND OF THE NAM/RAP13 925MB-H85 RH FIELD...THE TREND IS FOR THE OUTER EDGES OF THE STRATUS SHOULD BEGIN LIFTING AND ERODING FROM FROM SOUTHWEST TO NORTHEAST THIS AFTERNOON. CONCUR WITH THIS THOUGHT AS LOW LEVEL WARM AIR ADVECTION BEGINS IN THE SOUTHWEST AND VERY SLOWLY PERMEATES TO THE NORTHEAST. HOWEVER IT APPEARS THE EAST CENTRAL ZONES WILL LIKELY REMAIN UNDER THE LOW CLOUDS FOR MOST OF THE AFTERNOON. SURFACE ANALYSIS SHOWS BRISK TO WINDY CONDITIONS OVER WESTERN AND CENTRAL NORTH DAKOTA. THE STRONGEST WINDS WERE LOCATED ROUGHLY ALONG AND NORTH OF HIGHWAY 2. A 3HR PRESSURE RISE MAX IN SOUTHEAST SASKATCHEWAN IS FORECAST TO MOVE INTO EASTERN NORTH DAKOTA DURING THE AFTERNOON. LATEST NAM SOUNDINGS SHOW THE STRONGEST WINDS WILL OCCUR NOW THROUGH 21Z THEN BEGIN TO SUBSIDE. WIND ADVISORY CRITERIA WILL BE MONITORED AS ISOLATED INSTANCES OF CRITERIA HAVE BEEN MET NEAR THE TURTLE MOUNTAINS. IF THIS BECOMES MORE WIDESPREAD IN THE NEXT FEW HOURS...A WIND ADVISORY WILL BE INITIATED. FOR NOW...WILL CONTINUE TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK AND EXPAND IT FURTHER NORTH AND WEST. WILL METWATCH THEN ADJUST IF NEED BE. MINOR UPDATES TO WINDS AND SKY GRIDS BASED ON CURRENT DATA. UPDATE ISSUED AT 554 AM CST SAT NOV 9 2013 UPDATE TO ADD FLURRIES TO THE NORTHWEST AND NORTH CENTRAL GIVEN THE 10-11 UTC OBSERVATIONS. CONTINUED TO FOLLOW THE RAP FOR CLOUD COVER...THE LATEST CYCLE BEING 10 UTC. THE RAP CONTINUES TO HANDLE WELL THE EXPANSE OF STRATUS SPREADING ACROSS WESTERN AND CENTRAL NORTH DAKOTA FROM CANADA. THE 06 UTC NAM/GFS SUPPORT LITTLE TEMPERATURE RECOVERY ACROSS THE AREA TODAY...WITH WIDESPREAD HIGHS IN THE LOW TO MID 30S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CST SAT NOV 9 2013 THE HIGHLIGHT OF THE SHORT TERM WILL BE STRONG WINDS TODAY. STRONG NORTHWEST WINDS ARE FORECAST ACROSS CENTRAL NORTH DAKOTA TODAY ON THE BACKSIDE OF THE DEPARTING LOW INTO THE GREAT LAKES. THE 00 UTC NAM/GFS BUFR SOUNDINGS INDICATE NEAR ADIABATIC LAPSE RATES THROUGH 850 MB IN LOW LEVEL COLD AIR ADVECTION...WITH 35 TO 40 KTS AT THE TOP OF THE MIXED LAYER. THIS RESULTS IN BORDERLINE ADVISORY LEVEL WIND GUSTS ACROSS THE JAMES RIVER VALLEY LATE THIS MORNING AND THROUGH THE AFTERNOON. GIVEN THEN BORDERLINE ADVISORY LEVEL GUSTS...WILL HOLD OFF ON AN ADVISORY. THE SURFACE PRESSURE GRADIENT AND THUS WINDS WEAKEN ACROSS THE WEST WHERE HIGH PRESSURE WILL BE BUILDING IN THROUGH THE AFTERNOON. THE OTHER CHALLENGE FOR TODAY WILL BE CLOUD COVER. FOLLOWED CLOSELY TO THE 08 UTC RAP FOR CLOUD COVER WHICH HAS HAD A GOOD HANDLE ON THE STRATUS ACROSS THE REGION THROUGH THE NIGHT AND DEPICTS A SLOW CLEARING TREND AS HIGH PRESSURE BUILDS IN. THE JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS WILL LIKELY BE HELD UNDER THE STRATUS THROUGH EARLY EVENING. GIVEN ITS PREFERRED CLOUD COVER...ALSO FOLLOWED THE 08 UTC RAP FOR TEMPERATURES FOR TODAY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 314 AM CST SAT NOV 9 2013 THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD IS SNOWFALL AMOUNTS AND LOCATION SUNDAY NIGHT INTO MONDAY. MODEL AGREEMENT STILL ON TRACK...INDICATING A COLD FRONT PASSAGE SUNDAY AFTERNOON...POSSIBLY ACCOMPANIED BY SOME LIGHT SNOW IN THE WEST. HAVE INCREASED POST-FRONTAL WINDS ABOVE THE CONSENSUS BLEND...WITH GUSTS AROUND 35 MPH EXPECTED. THE MAIN PRECIPITATION IS EXPECTED TO OCCUR SUNDAY NIGHT INTO EARLY MONDAY OVER THE SOUTHWEST COUNTIES. A BLEND OF GFS/ECMWF QPF AND SNOW RATIOS AVERAGING 15:1 RESULT IN 1 TO 3 INCH SNOWFALL AMOUNTS FROM TROTTERS...TO DICKINSON AND SELFRIDGE...AND POINTS SOUTHWEST. WIND GUSTS TO 25 MPH SUNDAY NIGHT COULD PRODUCE SNOW BLOWING AND DRIFTING SNOW. WIND CHILL VALUES WILL LIKELY APPROACH 10 BELOW ZERO IN THE TURTLE LAKES REGION SUNDAY NIGHT. FRIGID CONDITIONS ARE ALSO EXPECTED MONDAY NIGHT...WITH LOWS IN THE SINGLE DIGITS EAST TO MID TEENS WEST. TEMPERATURES ARE EXPECTED TO WARM TUESDAY THROUGH FRIDAY WITH LOW CHANCES OF ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1203 PM CST SAT NOV 9 2013 CIGS WILL BEGIN IN MVFR STATUS BUT GRADUALLY IMPROVE TO LOW VFR THROUGH 00Z SUNDAY. GUSTY NORTHWEST WINDS OF 25KT WITH GUSTS TO 38KT CAN BE EXPECTED AT KJMS THROUGH 22Z SUNDAY AS WELL. WINDS WILL DIMINISH THIS EVENING WITH MAINLY SCT TO BKN VFR CIGS THEREAFTER. AN ARCTIC SURGE OF COLDER AIR WILL PUSH INTO KISN BETWEEN 15Z AND 18Z SUNDAY. EXPECT CIGS TO PERIODICALLY LOWER TO MVFR STATUS ONCE AGAIN...DEVELOPING FROM NORTHERN AERODROMES ON SOUTHWARD AFTER 18Z SUNDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ004-005-011>013- 021>023-025-036-037-047-048-050-051. && $$ UPDATE...KS SHORT TERM...AYD LONG TERM...RP KINNEY AVIATION...KS
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1014 AM CST SAT NOV 9 2013 .UPDATE... ISSUED AT 1014 AM CST SAT NOV 9 2013 MAIN CHALLENGE FOR THE MORNING UPDATE IS WIND. SURFACE OBSERVATIONS FROM RUGBY TO CARRINGTON HAVE ALREADY EXCEEDED A SUSTAINED 26 KTS (30 MPH) WITH A GUST TO 51 MPH AT CARRINGTON. EVEN FARGO HAD A PEAK WIND TO 43 MPH AT 0830 CST. WITH THE RAP SHOWING AT LEAST 35 KTS AT 925 HPA TO MIX TO THE SURFACE AND UP TO 40 KTS AT 850 HPA IF THE BOUNDARY LAYER CAN DEEPEN THAT FAR WITH CLOUD COVER...THINK A WIND ADVISORY IS PRUDENT FOR SOUTHEAST ND INTO THE DEVILS LAKE BASIN UNTIL 00 UTC TONIGHT. TRUE ADVISORY CRITERIA MAY NOT BE MET AT ALL LOCATIONS AND BE INTERMITTENT...BUT EXPECT NORTHWEST WIND BETWEEN 25 AND 35 MPH WITH GUSTS UP TO 45 MPH. SCATTERED SNOW SHOWERS WILL BE CONFINED MAINLY TO NORTHWEST MN THROUGH THE DAY. WEB CAMS IN THIS AREA SUGGEST REDUCTIONS IN VISIBILITY INTO THE 2 TO 5 SM RANGE ARE DUE MORE TO PATCHY FOG AND DRIZZLE THAN SNOW...SO ADDED FOG THROUGH 18 UTC AND DRIZZLE THROUGH 00 UTC. SURFACE TEMPERATURES SHOULD REMAIN STEADY AT OR SLIGHTLY ABOVE FREEZING...SO THERE MAY BE SOME SLICK SPOTS...BUT DO NOT ANTICIPATE MUCH IF ANY ADDITIONAL SNOW ACCUMULATION OR DRIZZLE FREEZING ON IMPACT. REST OF THE FORECAST IN GOOD SHAPE WITH NO MAJOR CHANGES AT THIS TIME. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 322 AM CST SAT NOV 9 2013 THE MAIN CONCERN FOR TODAY WILL BE WIND SPEEDS. LOW PRESSURE IS PROPAGATING EASTWARD...LEAVING THE REGION IN A WEAK COLD AIR ADVECTION REGIME. MODELS INDICATE UNIDIRECTIONAL FLOW TO 925MB BY LATE MORNING ACROSS MUCH OF THE FA...AND UP TO 850MB ACROSS SOUTHEAST NORTH DAKOTA. MODELS INDICATE 925MB WIND SPEEDS 30-35 KNOTS...AND 850MB WIND SPEEDS AROUND 40 KNOTS (WEAKER ACROSS THE NORTHERN FA). WITH THE MODELS INDICATING DEEPER MIXING ACROSS SOUTHEAST NORTH DAKOTA...THIS AREA WILL BE VERY CLOSE TO WIND ADVISORY CRITERIA (MOS GUIDANCE INDICATES AROUND 26 KNOTS SUSTAINED). CLOUDS ARE EXPECTED TO REMAIN THROUGH MUCH OF THE DAY...WHICH COULD LIMIT MIXING POTENTIAL...AND WILL HOLD OFF ON AN ADVISORY. OTHERWISE...SATELLITE IMAGERY INDICATES CLOUDS UPSTREAM...AND UNTIL THE SURFACE RIDGE MOVES THROUGH THE REGION TONIGHT...DO NOT SEE ANY POTENTIAL FOR CLEARING (DELAYED THE CLEARING UNTIL TONIGHT). TEMPERATURES WILL START OUT WARM TODAY...BUT WILL LIKELY ONLY RISE A FEW DEGREES. A STRONGER UPPER WAVE IS ENTERING SOUTHERN MANITOBA...AND WILL BRING SNOW SHOWERS TO NORTHWEST MINNESOTA TODAY. NOT MUCH ACCUMULATION EXPECTED...BUT COULD BE UP TO AN INCH. FLURRIES POSSIBLE ELSEWHERE GIVEN CAA AND LOW CLOUDS IN PLACE. LOW LEVEL RIDGE MOVING THROUGH THE REGION TONIGHT SHOULD BE ABLE TO CLEAR THE SKY. ASSUMING THAT THE SKY DOES CLEAR...TEMPERATURES WILL BE IN THE TEENS (FOLLOWING COLDER GUIDANCE WHICH HAS VERIFIED BETTER THE PAST WEEK). ON SUNDAY...MAX TEMPERATURES WILL BE DETERMINED BY THE TIMING OF A STRONG COLD FRONT. MOST MODELS INDICATE THIS FEATURE WILL MOVE THROUGH THE REGION DURING THE AFTERNOON HOURS...WHICH SHOULD PROVIDE MOST AREAS ENOUGH TIME TO WARM INTO THE UPPER 30S OR LOW- MID 40S (ESPECIALLY RIGHT AHEAD OF THE COLD FRONT WHERE LOW LEVEL FLOW WILL BE WESTERLY). STAYED CONSERVATIVE WITH THE MAX TEMP FORECAST...ALTHOUGH OUR FORECAST COULD BE 5F-8F TOO COOL. THE STRONGEST SYNOPTIC FORCING WILL BE ACROSS NORTHWEST MINNESOTA...CLOSER TO THE UPPER WAVE...AND WE HAVE LOWER END POPS HERE. ALSO...INCREASED WIND SPEEDS BEHIND THE FROPA GIVEN THE STRONG COLD AIR ADVECTION EXPECTED (MODELS ONLY SHOWING WINDS ALOFT OF 25-30 KNOTS...SO IF THAT IS TRUE THIS WOULD BE SHORT OF ADVISORY CRITERIA...JUST A BRIEF PERIOD OF GUSTY WINDS). .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 322 AM CST SAT NOV 9 2013 SUNDAY NIGHT-MONDAY NIGHT...STRONG COLD FRONT WILL CONTINUE TO SWEEP THROUGH THE REGION SUNDAY NIGHT...WITH HIGH PRESSURE FOLLOWING FOR MONDAY INTO MONDAY NIGHT. MODELS DIFFER A LITTLE BIT WITH 850MB TEMPERATURE VALUES ON MONDAY...BUT GENERALLY -12C TO -18C. NEEDLESS TO SAY...TEMPERATURES WILL BE WELL BELOW NORMAL VALUES. FOLLOWED THE COLDER GUIDANCE CONSIDERING MODEL PERFORMANCE FOR THIS PAST WEEK. TUESDAY-FRIDAY...TRANSITORY MID/UPPER RIDGING WILL SLIDE ACROSS THE AREA ON TUESDAY AS THE SFC HIGH CONTINUES SOUTHWARD ACROSS THE PLAINS. INCREASING WARM ADVECTION AND SOUTHWEST SFC WINDS SHOULD ALLOW FOR SOME DECENT TEMP RECOVERY...LIMITED SOMEWHAT THOUGH BY THE VERY CHILLY START TO THE DAY...KEEPING HIGH TEMPS A BIT BELOW NORMAL. TUESDAY NIGHT WILL NOT BE AS COLD...WITH CONTINUED WARM ADVECTION AND A STRENGTHENING PRESSURE GRADIENT KEEPING WINDS UP. THE THERMAL RIDGE AXIS WILL MOVE ACROSS THE AREA ON WEDNESDAY AS A RELATIVELY WEAK COLD FRONT ADVANCES TOWARDS THE REGION. WITH FAVORABLE WEST WINDS...TEMPS INTO THE 40S IN SOME AREAS CAN BE EXPECTED. BEYOND WEDNESDAY...MODELS SHOW SOME DEGREE OF NORTHWEST FLOW ALOFT DEVELOPING FOR THE LATTER HALF OF THE WEEK. ALTHOUGH THE TIMING AND PLACEMENT VARY AMONG MODELS...SEVERAL WEAK SHORTWAVE TROUGHS WILL LIKELY PASS THROUGH THE REGION LATE IN THE WEEK. ANY IMPULSE MAY GENERATE LIGHT PRECIP...BUT NO MAJOR SYSTEMS ARE EXPECTED. TEMPS LOOK TO REMAIN SEASONABLE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1014 AM CST SAT NOV 9 2013 CIGS ACROSS THE REGION TRANSITION WEST TO EAST FROM MVFR TO IFR. LATEST HRRR GUIDANCE INDICATES THERE WILL BE SLOW IMPROVEMENT THROUGH THE PERIOD...WITH CLEARING POSSIBLE LATER THIS EVENING OR EVEN MORE INTO SUNDAY MORNING. GUSTY NORTHWEST WINDS...BRIEFLY UP TO 35 KTS VCNTY KFAR...THROUGH LATE AFTERNOON BEFORE DECREASING THIS EVENING. SCATTERED SNOW SHOWERS EXPECTED WITHIN NORTHWEST MINNESOTA...WITH FLURRIES TO THE WEST. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ006-014-015-024- 026-028-029-038-039-049-052-053. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...TG LONG TERM...TG/MAKOWSKI AVIATION...WJB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
925 AM CST SAT NOV 9 2013 .UPDATE... ISSUED AT 924 AM CST SAT NOV 9 2013 CARRINGTON HAD A GUST TO 51 MPH...WITH WIND 30 MPH SUSTAINED AT MINOT AND RUGBY. A WIND ADVISORY HAS BEEN ISSUED FOR NORTH CENTRAL AND EAST CENTRAL NORTH DAKOTA THROUGH 00Z SUNDAY AS THE STRONG WINDS WILL SPREAD SOUTH THROUGH THE AFTERNOON. UPDATES FORTHCOMING TO REST OF TEXT PRODUCTS. UPDATE ISSUED AT 821 AM CST SAT NOV 9 2013 LATEST FOG/STRATUS SATELLITE IMAGERY SHOWS A SWATH OF LOW CLOUDS WITH MULTIPLE BREAKS SOUTH OF INTERSTATE 94...WITH LESS BREAKS NORTH. USING A BLEND OF THE NAM/RAP13 925MB-H85 RH FIELD...THE TREND IS FOR THE OUTER EDGES OF THE STRATUS SHOULD BEGIN LIFTING AND ERODING FROM FROM SOUTHWEST TO NORTHEAST THIS AFTERNOON. CONCUR WITH THIS THOUGHT AS LOW LEVEL WARM AIR ADVECTION BEGINS IN THE SOUTHWEST AND VERY SLOWLY PERMEATES TO THE NORTHEAST. HOWEVER IT APPEARS THE EAST CENTRAL ZONES WILL LIKELY REMAIN UNDER THE LOW CLOUDS FOR MOST OF THE AFTERNOON. SURFACE ANALYSIS SHOWS BRISK TO WINDY CONDITIONS OVER WESTERN AND CENTRAL NORTH DAKOTA. THE STRONGEST WINDS WERE LOCATED ROUGHLY ALONG AND NORTH OF HIGHWAY 2. A 3HR PRESSURE RISE MAX IN SOUTHEAST SASKATCHEWAN IS FORECAST TO MOVE INTO EASTERN NORTH DAKOTA DURING THE AFTERNOON. LATEST NAM SOUNDINGS SHOW THE STRONGEST WINDS WILL OCCUR NOW THROUGH 21Z THEN BEGIN TO SUBSIDE. WIND ADVISORY CRITERIA WILL BE MONITORED AS ISOLATED INSTANCES OF CRITERIA HAVE BEEN MET NEAR THE TURTLE MOUNTAINS. IF THIS BECOMES MORE WIDESPREAD IN THE NEXT FEW HOURS...A WIND ADVISORY WILL BE INITIATED. FOR NOW...WILL CONTINUE TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK AND EXPAND IT FURTHER NORTH AND WEST. WILL METWATCH THEN ADJUST IF NEED BE. MINOR UPDATES TO WINDS AND SKY GRIDS BASED ON CURRENT DATA. UPDATE ISSUED AT 554 AM CST SAT NOV 9 2013 UPDATE TO ADD FLURRIES TO THE NORTHWEST AND NORTH CENTRAL GIVEN THE 10-11 UTC OBSERVATIONS. CONTINUED TO FOLLOW THE RAP FOR CLOUD COVER...THE LATEST CYCLE BEING 10 UTC. THE RAP CONTINUES TO HANDLE WELL THE EXPANSE OF STRATUS SPREADING ACROSS WESTERN AND CENTRAL NORTH DAKOTA FROM CANADA. THE 06 UTC NAM/GFS SUPPORT LITTLE TEMPERATURE RECOVERY ACROSS THE AREA TODAY...WITH WIDESPREAD HIGHS IN THE LOW TO MID 30S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CST SAT NOV 9 2013 THE HIGHLIGHT OF THE SHORT TERM WILL BE STRONG WINDS TODAY. STRONG NORTHWEST WINDS ARE FORECAST ACROSS CENTRAL NORTH DAKOTA TODAY ON THE BACKSIDE OF THE DEPARTING LOW INTO THE GREAT LAKES. THE 00 UTC NAM/GFS BUFR SOUNDINGS INDICATE NEAR ADIABATIC LAPSE RATES THROUGH 850 MB IN LOW LEVEL COLD AIR ADVECTION...WITH 35 TO 40 KTS AT THE TOP OF THE MIXED LAYER. THIS RESULTS IN BORDERLINE ADVISORY LEVEL WIND GUSTS ACROSS THE JAMES RIVER VALLEY LATE THIS MORNING AND THROUGH THE AFTERNOON. GIVEN THEN BORDERLINE ADVISORY LEVEL GUSTS...WILL HOLD OFF ON AN ADVISORY. THE SURFACE PRESSURE GRADIENT AND THUS WINDS WEAKEN ACROSS THE WEST WHERE HIGH PRESSURE WILL BE BUILDING IN THROUGH THE AFTERNOON. THE OTHER CHALLENGE FOR TODAY WILL BE CLOUD COVER. FOLLOWED CLOSELY TO THE 08 UTC RAP FOR CLOUD COVER WHICH HAS HAD A GOOD HANDLE ON THE STRATUS ACROSS THE REGION THROUGH THE NIGHT AND DEPICTS A SLOW CLEARING TREND AS HIGH PRESSURE BUILDS IN. THE JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS WILL LIKELY BE HELD UNDER THE STRATUS THROUGH EARLY EVENING. GIVEN ITS PREFERRED CLOUD COVER...ALSO FOLLOWED THE 08 UTC RAP FOR TEMPERATURES FOR TODAY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 314 AM CST SAT NOV 9 2013 THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD IS SNOWFALL AMOUNTS AND LOCATION SUNDAY NIGHT INTO MONDAY. MODEL AGREEMENT STILL ON TRACK...INDICATING A COLD FRONT PASSAGE SUNDAY AFTERNOON...POSSIBLY ACCOMPANIED BY SOME LIGHT SNOW IN THE WEST. HAVE INCREASED POST-FRONTAL WINDS ABOVE THE CONSENSUS BLEND...WITH GUSTS AROUND 35 MPH EXPECTED. THE MAIN PRECIPITATION IS EXPECTED TO OCCUR SUNDAY NIGHT INTO EARLY MONDAY OVER THE SOUTHWEST COUNTIES. A BLEND OF GFS/ECMWF QPF AND SNOW RATIOS AVERAGING 15:1 RESULT IN 1 TO 3 INCH SNOWFALL AMOUNTS FROM TROTTERS...TO DICKINSON AND SELFRIDGE...AND POINTS SOUTHWEST. WIND GUSTS TO 25 MPH SUNDAY NIGHT COULD PRODUCE SNOW BLOWING AND DRIFTING SNOW. WIND CHILL VALUES WILL LIKELY APPROACH 10 BELOW ZERO IN THE TURTLE LAKES REGION SUNDAY NIGHT. FRIGID CONDITIONS ARE ALSO EXPECTED MONDAY NIGHT...WITH LOWS IN THE SINGLE DIGITS EAST TO MID TEENS WEST. TEMPERATURES ARE EXPECTED TO WARM TUESDAY THROUGH FRIDAY WITH LOW CHANCES OF ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 554 AM CST SAT NOV 9 2013 WIDESPREAD MVFR STRATUS...WITH ISOLATED POCKETS OF IFR...WILL IMPACT MUCH OF WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING AND INTO THE AFTERNOON. NORTHWEST WIND GUSTS OF 30-35 KTS WILL CONTINUE INTO SATURDAY AT KBIS...KMOT AND KJMS. GUSTS OF 25-30 KTS ARE POSSIBLE AT KDIK AND KISN. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ004-005-011>013- 021>023-025-036-037-047-048-050-051. && $$ UPDATE...KS SHORT TERM...AYD LONG TERM...RP KINNEY AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
821 AM CST SAT NOV 9 2013 .UPDATE... ISSUED AT 821 AM CST SAT NOV 9 2013 LATEST FOG/STRATUS SATELLITE IMAGERY SHOWS A SWATH OF LOW CLOUDS WITH MULTIPLE BREAKS SOUTH OF INTERSTATE 94...WITH LESS BREAKS NORTH. USING A BLEND OF THE NAM/RAP13 925MB-H85 RH FIELD...THE TREND IS FOR THE OUTER EDGES OF THE STRATUS SHOULD BEGIN LIFTING AND ERODING FROM FROM SOUTHWEST TO NORTHEAST THIS AFTERNOON. CONCUR WITH THIS THOUGHT AS LOW LEVEL WARM AIR ADVECTION BEGINS IN THE SOUTHWEST AND VERY SLOWLY PERMEATES TO THE NORTHEAST. HOWEVER IT APPEARS THE EAST CENTRAL ZONES WILL LIKELY REMAIN UNDER THE LOW CLOUDS FOR MOST OF THE AFTERNOON. SURFACE ANALYSIS SHOWS BRISK TO WINDY CONDITIONS OVER WESTERN AND CENTRAL NORTH DAKOTA. THE STRONGEST WINDS WERE LOCATED ROUGHLY ALONG AND NORTH OF HIGHWAY 2. A 3HR PRESSURE RISE MAX IN SOUTHEAST SASKATCHEWAN IS FORECAST TO MOVE INTO EASTERN NORTH DAKOTA DURING THE AFTERNOON. LATEST NAM SOUNDINGS SHOW THE STRONGEST WINDS WILL OCCUR NOW THROUGH 21Z THEN BEGIN TO SUBSIDE. WIND ADVISORY CRITERIA WILL BE MONITORED AS ISOLATED INSTANCES OF CRITERIA HAVE BEEN MET NEAR THE TURTLE MOUNTAINS. IF THIS BECOMES MORE WIDESPREAD IN THE NEXT FEW HOURS...A WIND ADVISORY WILL BE INITIATED. FOR NOW...WILL CONTINUE TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK AND EXPAND IT FURTHER NORTH AND WEST. WILL METWATCH THEN ADJUST IF NEED BE. MINOR UPDATES TO WINDS AND SKY GRIDS BASED ON CURRENT DATA. UPDATE ISSUED AT 554 AM CST SAT NOV 9 2013 UPDATE TO ADD FLURRIES TO THE NORTHWEST AND NORTH CENTRAL GIVEN THE 10-11 UTC OBSERVATIONS. CONTINUED TO FOLLOW THE RAP FOR CLOUD COVER...THE LATEST CYCLE BEING 10 UTC. THE RAP CONTINUES TO HANDLE WELL THE EXPANSE OF STRATUS SPREADING ACROSS WESTERN AND CENTRAL NORTH DAKOTA FROM CANADA. THE 06 UTC NAM/GFS SUPPORT LITTLE TEMPERATURE RECOVERY ACROSS THE AREA TODAY...WITH WIDESPREAD HIGHS IN THE LOW TO MID 30S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CST SAT NOV 9 2013 THE HIGHLIGHT OF THE SHORT TERM WILL BE STRONG WINDS TODAY. STRONG NORTHWEST WINDS ARE FORECAST ACROSS CENTRAL NORTH DAKOTA TODAY ON THE BACKSIDE OF THE DEPARTING LOW INTO THE GREAT LAKES. THE 00 UTC NAM/GFS BUFR SOUNDINGS INDICATE NEAR ADIABATIC LAPSE RATES THROUGH 850 MB IN LOW LEVEL COLD AIR ADVECTION...WITH 35 TO 40 KTS AT THE TOP OF THE MIXED LAYER. THIS RESULTS IN BORDERLINE ADVISORY LEVEL WIND GUSTS ACROSS THE JAMES RIVER VALLEY LATE THIS MORNING AND THROUGH THE AFTERNOON. GIVEN THEN BORDERLINE ADVISORY LEVEL GUSTS...WILL HOLD OFF ON AN ADVISORY. THE SURFACE PRESSURE GRADIENT AND THUS WINDS WEAKEN ACROSS THE WEST WHERE HIGH PRESSURE WILL BE BUILDING IN THROUGH THE AFTERNOON. THE OTHER CHALLENGE FOR TODAY WILL BE CLOUD COVER. FOLLOWED CLOSELY TO THE 08 UTC RAP FOR CLOUD COVER WHICH HAS HAD A GOOD HANDLE ON THE STRATUS ACROSS THE REGION THROUGH THE NIGHT AND DEPICTS A SLOW CLEARING TREND AS HIGH PRESSURE BUILDS IN. THE JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS WILL LIKELY BE HELD UNDER THE STRATUS THROUGH EARLY EVENING. GIVEN ITS PREFERRED CLOUD COVER...ALSO FOLLOWED THE 08 UTC RAP FOR TEMPERATURES FOR TODAY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 314 AM CST SAT NOV 9 2013 THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD IS SNOWFALL AMOUNTS AND LOCATION SUNDAY NIGHT INTO MONDAY. MODEL AGREEMENT STILL ON TRACK...INDICATING A COLD FRONT PASSAGE SUNDAY AFTERNOON...POSSIBLY ACCOMPANIED BY SOME LIGHT SNOW IN THE WEST. HAVE INCREASED POST-FRONTAL WINDS ABOVE THE CONSENSUS BLEND...WITH GUSTS AROUND 35 MPH EXPECTED. THE MAIN PRECIPITATION IS EXPECTED TO OCCUR SUNDAY NIGHT INTO EARLY MONDAY OVER THE SOUTHWEST COUNTIES. A BLEND OF GFS/ECMWF QPF AND SNOW RATIOS AVERAGING 15:1 RESULT IN 1 TO 3 INCH SNOWFALL AMOUNTS FROM TROTTERS...TO DICKINSON AND SELFRIDGE...AND POINTS SOUTHWEST. WIND GUSTS TO 25 MPH SUNDAY NIGHT COULD PRODUCE SNOW BLOWING AND DRIFTING SNOW. WIND CHILL VALUES WILL LIKELY APPROACH 10 BELOW ZERO IN THE TURTLE LAKES REGION SUNDAY NIGHT. FRIGID CONDITIONS ARE ALSO EXPECTED MONDAY NIGHT...WITH LOWS IN THE SINGLE DIGITS EAST TO MID TEENS WEST. TEMPERATURES ARE EXPECTED TO WARM TUESDAY THROUGH FRIDAY WITH LOW CHANCES OF ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 554 AM CST SAT NOV 9 2013 WIDESPREAD MVFR STRATUS...WITH ISOLATED POCKETS OF IFR...WILL IMPACT MUCH OF WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING AND INTO THE AFTERNOON. NORTHWEST WIND GUSTS OF 30-35 KTS WILL CONTINUE INTO SATURDAY AT KBIS...KMOT AND KJMS. GUSTS OF 25-30 KTS ARE POSSIBLE AT KDIK AND KISN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...AYD LONG TERM...RP KINNEY AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
628 AM CST SAT NOV 9 2013 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 322 AM CST SAT NOV 9 2013 THE MAIN CONCERN FOR TODAY WILL BE WIND SPEEDS. LOW PRESSURE IS PROPAGATING EASTWARD...LEAVING THE REGION IN A WEAK COLD AIR ADVECTION REGIME. MODELS INDICATE UNIDIRECTIONAL FLOW TO 925MB BY LATE MORNING ACROSS MUCH OF THE FA...AND UP TO 850MB ACROSS SOUTHEAST NORTH DAKOTA. MODELS INDICATE 925MB WIND SPEEDS 30-35 KNOTS...AND 850MB WIND SPEEDS AROUND 40 KNOTS (WEAKER ACROSS THE NORTHERN FA). WITH THE MODELS INDICATING DEEPER MIXING ACROSS SOUTHEAST NORTH DAKOTA...THIS AREA WILL BE VERY CLOSE TO WIND ADVISORY CRITERIA (MOS GUIDANCE INDICATES AROUND 26 KNOTS SUSTAINED). CLOUDS ARE EXPECTED TO REMAIN THROUGH MUCH OF THE DAY...WHICH COULD LIMIT MIXING POTENTIAL...AND WILL HOLD OFF ON AN ADVISORY. OTHERWISE...SATELLITE IMAGERY INDICATES CLOUDS UPSTREAM...AND UNTIL THE SURFACE RIDGE MOVES THROUGH THE REGION TONIGHT...DO NOT SEE ANY POTENTIAL FOR CLEARING (DELAYED THE CLEARING UNTIL TONIGHT). TEMPERATURES WILL START OUT WARM TODAY...BUT WILL LIKELY ONLY RISE A FEW DEGREES. A STRONGER UPPER WAVE IS ENTERING SOUTHERN MANITOBA...AND WILL BRING SNOW SHOWERS TO NORTHWEST MINNESOTA TODAY. NOT MUCH ACCUMULATION EXPECTED...BUT COULD BE UP TO AN INCH. FLURRIES POSSIBLE ELSEWHERE GIVEN CAA AND LOW CLOUDS IN PLACE. LOW LEVEL RIDGE MOVING THROUGH THE REGION TONIGHT SHOULD BE ABLE TO CLEAR THE SKY. ASSUMING THAT THE SKY DOES CLEAR...TEMPERATURES WILL BE IN THE TEENS (FOLLOWING COLDER GUIDANCE WHICH HAS VERIFIED BETTER THE PAST WEEK). ON SUNDAY...MAX TEMPERATURES WILL BE DETERMINED BY THE TIMING OF A STRONG COLD FRONT. MOST MODELS INDICATE THIS FEATURE WILL MOVE THROUGH THE REGION DURING THE AFTERNOON HOURS...WHICH SHOULD PROVIDE MOST AREAS ENOUGH TIME TO WARM INTO THE UPPER 30S OR LOW- MID 40S (ESPECIALLY RIGHT AHEAD OF THE COLD FRONT WHERE LOW LEVEL FLOW WILL BE WESTERLY). STAYED CONSERVATIVE WITH THE MAX TEMP FORECAST...ALTHOUGH OUR FORECAST COULD BE 5F-8F TOO COOL. THE STRONGEST SYNOPTIC FORCING WILL BE ACROSS NORTHWEST MINNESOTA...CLOSER TO THE UPPER WAVE...AND WE HAVE LOWER END POPS HERE. ALSO...INCREASED WIND SPEEDS BEHIND THE FROPA GIVEN THE STRONG COLD AIR ADVECTION EXPECTED (MODELS ONLY SHOWING WINDS ALOFT OF 25-30 KNOTS...SO IF THAT IS TRUE THIS WOULD BE SHORT OF ADVISORY CRITERIA...JUST A BRIEF PERIOD OF GUSTY WINDS). .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 322 AM CST SAT NOV 9 2013 SUNDAY NIGHT-MONDAY NIGHT...STRONG COLD FRONT WILL CONTINUE TO SWEEP THROUGH THE REGION SUNDAY NIGHT...WITH HIGH PRESSURE FOLLOWING FOR MONDAY INTO MONDAY NIGHT. MODELS DIFFER A LITTLE BIT WITH 850MB TEMPERATURE VALUES ON MONDAY...BUT GENERALLY -12C TO -18C. NEEDLESS TO SAY...TEMPERATURES WILL BE WELL BELOW NORMAL VALUES. FOLLOWED THE COLDER GUIDANCE CONSIDERING MODEL PERFORMANCE FOR THIS PAST WEEK. TUESDAY-FRIDAY...TRANSITORY MID/UPPER RIDGING WILL SLIDE ACROSS THE AREA ON TUESDAY AS THE SFC HIGH CONTINUES SOUTHWARD ACROSS THE PLAINS. INCREASING WARM ADVECTION AND SOUTHWEST SFC WINDS SHOULD ALLOW FOR SOME DECENT TEMP RECOVERY...LIMITED SOMEWHAT THOUGH BY THE VERY CHILLY START TO THE DAY...KEEPING HIGH TEMPS A BIT BELOW NORMAL. TUESDAY NIGHT WILL NOT BE AS COLD...WITH CONTINUED WARM ADVECTION AND A STRENGTHENING PRESSURE GRADIENT KEEPING WINDS UP. THE THERMAL RIDGE AXIS WILL MOVE ACROSS THE AREA ON WEDNESDAY AS A RELATIVELY WEAK COLD FRONT ADVANCES TOWARDS THE REGION. WITH FAVORABLE WEST WINDS...TEMPS INTO THE 40S IN SOME AREAS CAN BE EXPECTED. BEYOND WEDNESDAY...MODELS SHOW SOME DEGREE OF NORTHWEST FLOW ALOFT DEVELOPING FOR THE LATTER HALF OF THE WEEK. ALTHOUGH THE TIMING AND PLACEMENT VARY AMONG MODELS...SEVERAL WEAK SHORTWAVE TROUGHS WILL LIKELY PASS THROUGH THE REGION LATE IN THE WEEK. ANY IMPULSE MAY GENERATE LIGHT PRECIP...BUT NO MAJOR SYSTEMS ARE EXPECTED. TEMPS LOOK TO REMAIN SEASONABLE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 628 AM CST SAT NOV 9 2013 CIGS ACROSS THE REGION TRANSITION WEST TO EAST FROM MVFR TO IFR TO LIFR. LATEST RAP GUIDANCE INDICATES THERE WILL BE SLOW IMPROVEMENT THROUGH THE PERIOD...WITH CLEARING POSSIBLE LATER THIS EVENING OR EVEN MORE INTO SUNDAY MORNING. SCATTERED SNOW SHOWERS EXPECTED WITHIN NORTHWEST MINNESOTA...WITH FLURRIES TO THE WEST. GUSTY NORTHWEST WINDS INTO THE AFTERNOON HOURS...DECREASING THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...TG LONG TERM...TG/MAKOWSKI AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
555 AM CST SAT NOV 9 2013 .UPDATE... ISSUED AT 554 AM CST SAT NOV 9 2013 UPDATE TO ADD FLURRIES TO THE NORTHWEST AND NORTH CENTRAL GIVEN THE 10-11 UTC OBSERVATIONS. CONTINUED TO FOLLOW THE RAP FOR CLOUD COVER...THE LATEST CYCLE BEING 10 UTC. THE RAP CONTINUES TO HANDLE WELL THE EXPANSE OF STRATUS SPREADING ACROSS WESTERN AND CENTRAL NORTH DAKOTA FROM CANADA. THE 06 UTC NAM/GFS SUPPORT LITTLE TEMPERATURE RECOVERY ACROSS THE AREA TODAY...WITH WIDESPREAD HIGHS IN THE LOW TO MID 30S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CST SAT NOV 9 2013 THE HIGHLIGHT OF THE SHORT TERM WILL BE STRONG WINDS TODAY. STRONG NORTHWEST WINDS ARE FORECAST ACROSS CENTRAL NORTH DAKOTA TODAY ON THE BACKSIDE OF THE DEPARTING LOW INTO THE GREAT LAKES. THE 00 UTC NAM/GFS BUFR SOUNDINGS INDICATE NEAR ADIABATIC LAPSE RATES THROUGH 850 MB IN LOW LEVEL COLD AIR ADVECTION...WITH 35 TO 40 KTS AT THE TOP OF THE MIXED LAYER. THIS RESULTS IN BORDERLINE ADVISORY LEVEL WIND GUSTS ACROSS THE JAMES RIVER VALLEY LATE THIS MORNING AND THROUGH THE AFTERNOON. GIVEN THEN BORDERLINE ADVISORY LEVEL GUSTS...WILL HOLD OFF ON AN ADVISORY. THE SURFACE PRESSURE GRADIENT AND THUS WINDS WEAKEN ACROSS THE WEST WHERE HIGH PRESSURE WILL BE BUILDING IN THROUGH THE AFTERNOON. THE OTHER CHALLENGE FOR TODAY WILL BE CLOUD COVER. FOLLOWED CLOSELY TO THE 08 UTC RAP FOR CLOUD COVER WHICH HAS HAD A GOOD HANDLE ON THE STRATUS ACROSS THE REGION THROUGH THE NIGHT AND DEPICTS A SLOW CLEARING TREND AS HIGH PRESSURE BUILDS IN. THE JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS WILL LIKELY BE HELD UNDER THE STRATUS THROUGH EARLY EVENING. GIVEN ITS PREFERRED CLOUD COVER...ALSO FOLLOWED THE 08 UTC RAP FOR TEMPERATURES FOR TODAY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 314 AM CST SAT NOV 9 2013 THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD IS SNOWFALL AMOUNTS AND LOCATION SUNDAY NIGHT INTO MONDAY. MODEL AGREEMENT STILL ON TRACK...INDICATING A COLD FRONT PASSAGE SUNDAY AFTERNOON...POSSIBLY ACCOMPANIED BY SOME LIGHT SNOW IN THE WEST. HAVE INCREASED POST-FRONTAL WINDS ABOVE THE CONSENSUS BLEND...WITH GUSTS AROUND 35 MPH EXPECTED. THE MAIN PRECIPITATION IS EXPECTED TO OCCUR SUNDAY NIGHT INTO EARLY MONDAY OVER THE SOUTHWEST COUNTIES. A BLEND OF GFS/ECMWF QPF AND SNOW RATIOS AVERAGING 15:1 RESULT IN 1 TO 3 INCH SNOWFALL AMOUNTS FROM TROTTERS...TO DICKINSON AND SELFRIDGE...AND POINTS SOUTHWEST. WIND GUSTS TO 25 MPH SUNDAY NIGHT COULD PRODUCE SNOW BLOWING AND DRIFTING SNOW. WIND CHILL VALUES WILL LIKELY APPROACH 10 BELOW ZERO IN THE TURTLE LAKES REGION SUNDAY NIGHT. FRIGID CONDITIONS ARE ALSO EXPECTED MONDAY NIGHT...WITH LOWS IN THE SINGLE DIGITS EAST TO MID TEENS WEST. TEMPERATURES ARE EXPECTED TO WARM TUESDAY THROUGH FRIDAY WITH LOW CHANCES OF ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 554 AM CST SAT NOV 9 2013 WIDESPREAD MVFR STRATUS...WITH ISOLATED POCKETS OF IFR...WILL IMPACT MUCH OF WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING AND INTO THE AFTERNOON. NORTHWEST WIND GUSTS OF 30-35 KTS WILL CONTINUE INTO SATURDAY AT KBIS...KMOT AND KJMS. GUSTS OF 25-30 KTS ARE POSSIBLE AT KDIK AND KISN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...AYD LONG TERM...RP KINNEY AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
315 AM CST SAT NOV 9 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CST SAT NOV 9 2013 THE HIGHLIGHT OF THE SHORT TERM WILL BE STRONG WINDS TODAY. STRONG NORTHWEST WINDS ARE FORECAST ACROSS CENTRAL NORTH DAKOTA TODAY ON THE BACKSIDE OF THE DEPARTING LOW INTO THE GREAT LAKES. THE 00 UTC NAM/GFS BUFR SOUNDINGS INDICATE NEAR ADIABATIC LAPSE RATES THROUGH 850 MB IN LOW LEVEL COLD AIR ADVECTION...WITH 35 TO 40 KTS AT THE TOP OF THE MIXED LAYER. THIS RESULTS IN BORDERLINE ADVISORY LEVEL WIND GUSTS ACROSS THE JAMES RIVER VALLEY LATE THIS MORNING AND THROUGH THE AFTERNOON. GIVEN THEN BORDERLINE ADVISORY LEVEL GUSTS...WILL HOLD OFF ON AN ADVISORY. THE SURFACE PRESSURE GRADIENT AND THUS WINDS WEAKEN ACROSS THE WEST WHERE HIGH PRESSURE WILL BE BUILDING IN THROUGH THE AFTERNOON. THE OTHER CHALLENGE FOR TODAY WILL BE CLOUD COVER. FOLLOWED CLOSELY TO THE 08 UTC RAP FOR CLOUD COVER WHICH HAS HAD A GOOD HANDLE ON THE STRATUS ACROSS THE REGION THROUGH THE NIGHT AND DEPICTS A SLOW CLEARING TREND AS HIGH PRESSURE BUILDS IN. THE JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS WILL LIKELY BE HELD UNDER THE STRATUS THROUGH EARLY EVENING. GIVEN ITS PREFERRED CLOUD COVER...ALSO FOLLOWED THE 08 UTC RAP FOR TEMPERATURES FOR TODAY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 314 AM CST SAT NOV 9 2013 THE MAIN FORECAST ISSUE IN THE LONG TERM PERIOD IS SNOWFALL AMOUNTS AND LOCATION SUNDAY NIGHT INTO MONDAY. MODEL AGREEMENT STILL ON TRACK...INDICATING A COLD FRONT PASSAGE SUNDAY AFTERNOON...POSSIBLY ACCOMPANIED BY SOME LIGHT SNOW IN THE WEST. HAVE INCREASED POST-FRONTAL WINDS ABOVE THE CONSENSUS BLEND...WITH GUSTS AROUND 35 MPH EXPECTED. THE MAIN PRECIPITATION IS EXPECTED TO OCCUR SUNDAY NIGHT INTO EARLY MONDAY OVER THE SOUTHWEST COUNTIES. A BLEND OF GFS/ECMWF QPF AND SNOW RATIOS AVERAGING 15:1 RESULT IN 1 TO 3 INCH SNOWFALL AMOUNTS FROM TROTTERS...TO DICKINSON AND SELFRIDGE...AND POINTS SOUTHWEST. WIND GUSTS TO 25 MPH SUNDAY NIGHT COULD PRODUCE SNOW BLOWING AND DRIFTING SNOW. WIND CHILL VALUES WILL LIKELY APPROACH 10 BELOW ZERO IN THE TURTLE LAKES REGION SUNDAY NIGHT. FRIGID CONDITIONS ARE ALSO EXPECTED MONDAY NIGHT...WITH LOWS IN THE SINGLE DIGITS EAST TO MID TEENS WEST. TEMPERATURES ARE EXPECTED TO WARM TUESDAY THROUGH FRIDAY WITH LOW CHANCES OF ADDITIONAL PRECIPITATION. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 314 AM CST SAT NOV 9 2013 WIDESPREAD MVFR STRATUS...WITH ISOLATED POCKETS OF IFR...WILL SLOWLY CLEAR FROM WEST TO EAST THROUGH THE DAY. NORTHWEST WIND GUSTS OF 30-35 KTS WILL CONTINUE INTO SATURDAY AT KBIS...KMOT AND KJMS. GUSTS OF 25-30 KTS ARE POSSIBLE AT KDIK AND KISN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...AYD LONG TERM...RP KINNEY AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1218 AM CST SAT NOV 9 2013 .UPDATE... ISSUED AT 1217 AM CST SAT NOV 9 2013 DID INCREASE CLOUD COVER FOR TONIGHT THROUGH THE DAY ON SATURDAY...FOLLOWING CLOSELY TO THE 04 UTC RAP WHICH HAS A GOOD HANDLE ON THE EXTENSIVE STRATUS ACROSS THE NORTHERN PLAINS AND CANADIAN PRAIRIES. OTHERWISE...THE FORECAST IS ON TRACK AND BLENDED TO THE 05-06 UTC OBSERVED TRENDS. UPDATE ISSUED AT 900 PM CST FRI NOV 8 2013 UPDATED TO ADD ISOLATED RAIN/SNOW SHOWERS ACROSS THE NORTH. LIGHT RADAR RETURNS AND A FEW SURFACE REPORTS OF LIGHT RAIN AT WATFORD CITY AND MINOT AND LIGHT SNOW FROM TIOGA. PRECIP SHOULD BE VERY ISOLATED IN NATURE AND NO ACCUMULATING SNOW EXPECTED. ALSO FURTHER INCREASED CLOUD COVER FOR THIS AREA. UPDATE ISSUED AT 703 PM CST FRI NOV 8 2013 SURFACE LOW WAS LOCATED OVER EASTERN ND AT 00Z. GUSTY WINDS WERE CONTINUING ACROSS THE WESTERN PART OF STATE WHERE STRONGER PRESSURE GRADIENT WAS LOCATED. AS THE LOW MOVES EASTWARD WINDS WILL PICK UP AGAIN ACROSS CENTRAL AND EASTERN SECTIONS TONIGHT. RADAR SHOWED SOME LINGERING LIGHT SHOWERS ACROSS FAR EASTERN CWA WHICH IS COVERED IN THE FORECAST THROUGH THE NEXT COUPLE HOURS. ONLY ADJUSTMENTS TO FORECAST WERE TO INCREASE CLOUD COVER THROUGH LATE EVENING BASED ON SATELLITE SHOWING HIGH CLOUDS MOVING INTO SW CWA AND LOWER CLOUDS ACROSS MUCH OF NORTHERN ND PUSHING SOUTHWARD. MODELS SHOW QUICK MOVING SHORTWAVE IN NORTHWEST FLOW MOVING FROM SASKATCHEWAN THROUGH NORTHEAST ND OVERNIGHT WHICH SHOULD HELP CLOUDS PERSIST. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 304 PM CST FRI NOV 8 2013 A PROGRESSIVE WESTERLY UPPER FLOW CONTINUES THIS AFTERNOON WITH A SHORTWAVE TROUGH ALOFT SLIDING INTO CENTRAL NORTH DAKOTA. LOCAL AND REGIONAL RADAR SHOWS PRECIPITATION DWINDLING IN THE WEST AND THIS WILL QUICKLY MOVE INTO SOUTH CENTRAL NORTH DAKOTA BY LATE AFTERNOON. THE WIND ADVISORY IN THE SOUTHWEST IS MARGINAL RIGHT NOW. VISIBLE SATELLITE AND OBSERVATIONS DO SHOW SOME POTENTIAL OF ADDITIONAL CLEARING IN THE NEXT FEW HOURS AND THIS MAY BE ENOUGH TO GET SOME OF THE STRONGER WINDS TO MIX DOWN TO THE SURFACE. WILL CONTINUE WITH THE WIND ADVISORY IN THE FAR SOUTHWEST. THE NEXT SHORTWAVE PER WATER VAPOR IMAGERY WAS SEEN IN CENTRAL SASKATCHEWAN. THIS IS FORECAST TO SHIFT SOUTHEAST TONIGHT...WHICH REPRESENTS THE MAIN LOW/MID LEVEL COLD POCKET/BAROCLINIC ZONE. THIS WILL ENTER NORTHERN NORTH DAKOTA TONIGHT AND PROGRESS SOUTHEAST INTO CENTRAL AND SOUTHERN NORTH DAKOTA SATURDAY. COLDER ON SATURDAY WITH HIGHS RANGING FROM THE LOWER 30S NORTH TO AROUND 40F FAR SOUTH. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 304 PM CST FRI NOV 8 2013 THE MAIN FORECAST HIGHLIGHT IN THE EXTENDED PERIOD WILL BE PRECIPITATION CHANCES AND MUCH COLDER TEMPERATURES BEHIND A BLAST OF MODIFIED ARCTIC AIR SUNDAY AND MONDAY. UTILIZED A MODEL BLEND WITH PERSISTENCE FOR SNOW CHANCES AND TIMING. THE GFS IS A LITTLE FASTER THAN THE ECMWF/GLOBAL GEM WITH THE TIMING OF THE COLD FRONT. THE GLOBAL GEM LOOKS TO BRING THE COLDEST AIR INTO WESTERN NORTH DAKOTA AND THE ECMWF KEEPS THE COLDER AIR OVER THE AREA LONGEST. THIS RESULTS IN VARYING SOLUTIONS OF SNOWFALL OVER SOUTHWEST NORTH DAKOTA SUNDAY NIGHT THROUGH MONDAY MORNING. BUT THE DIFFERENCES ARE SMALL ENOUGH THAT CONFIDENCE IN A MODEL BLEND WITH PERSISTENCE IS GREATER THAN AVERAGE. HAVE THEREFORE RAISED POPS OVER THE FAR SOUTHWEST SUNDAY NIGHT AND MONDAY MORNING. STILL PLENTY OF TIME FOR MODELS TO CHANGE BUT CURRENT INDICATIONS ARE THAT A SWATH OF A COUPLE INCHES COULD DEVELOP OVER SOUTHWEST NORTH DAKOTA AND TAPERING QUICKLY AS YOU MOVE NORTHEAST. AFTER DISCUSSIONS WITH SURROUNDING OFFICES HAVE STRAYED FROM THE DEFAULT MODEL BLEND FOR TEMPERATURES SUNDAY NIGHT THROUGH MONDAY NIGHT. BLENDED SOLUTION USUALLY TENDS TO NOT CAPTURE THE EXTENT OF THE COLD AIR WITH THESE ARCTIC SURGES...SO LOWERED TEMPERATURES SUNDAY NIGHT THROUGH MONDAY NIGHT. BEYOND THIS SUNDAY NIGHT THROUGH MONDAY NIGHT PERIOD AN ACTIVE FLOW PATTERN CONTINUES WITH A QUICK WARM-UP TUESDAY AND WEDNESDAY FOLLOWED BY ANOTHER COOL DOWN...ALTHOUGH NOT AS STRONG...THURSDAY AND FRIDAY. WEATHER DURING THE TUESDAY THROUGH FRIDAY PERIOD APPEARS RATHER QUIET OVER THE NORTHERN PLAINS WITH NO SIGNIFICANT PRECIPITATION EXPECTED AT THIS TIME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1217 AM CST SAT NOV 9 2013 WIDESPREAD MVFR STRATUS...WITH ISOLATED POCKETS OF IFR...WILL CONTINUE TONIGHT AND INTO THE DAY ON SATURDAY ACROSS WESTERN AND CENTRAL NORTH DAKOTA. NORTHWEST WIND GUSTS OF 25-30 KTS WILL CONTINUE TONIGHT INTO SATURDAY AT KBIS...KMOT AND KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...KS LONG TERM...TWH AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
958 PM CST SUN NOV 10 2013 NEW INFORMATION ADDED TO UPDATE SECTION .UPDATE... ISSUED AT 953 PM CST SUN NOV 10 2013 CONCERNED ABOUT A POSSIBLE HIGH-IMPACT SUB-ADVISORY (HISA) EVENT LATE TONIGHT INTO EARLY MONDAY. SNOWFALL SHOULD NOT BE A SIGNIFICANT PROBLEM...AS ACCUMS SHOULD BE AN INCH OR LESS IN MOST AREAS. HOWEVER... ROADS THAT ARE WET FROM RAIN OR MELTING SNOW WILL QUICKLY ICE UP AS ARCTIC AIR ARRIVES. ISSUED AN SPS AND UPDATED THE HWO TO GET THE WORD OUT. && .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 230 PM CST SUN NOV 10 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE HIGH PRESSURE MOVING SOUTHEAST ACROSS THE MID-MISSISSIPPI VALLEY AND LOW PRESSURE DIVING SE ACROSS NORTHWEST ONTARIO. ATTACHED TO THE SURFACE LOW IS AN ARCTIC COLD FRONT WHICH IS PUSHING INTO THE NORTHERN PLAINS. LOW STRATO-CU ACROSS THE NORTH IS FINALLY EXITING NORTHEAST WISCONSIN AT THE MOMENT...BUT MID AND HIGH CLOUDS ARE ALREADY MOVING INTO THE STATE. AS A RESULT...CLOUDS WILL BE ON THE INCREASE FOR THE REST OF THE AFTERNOON. BUT QUICKLY ATTENTION WILL TURN TO THE ARCTIC FRONT. SNOW SHOWERS ARE OCCURRING ALONG THE FRONT OVER SOUTHWEST ONTARIO AND FAR NORTHERN MINNESOTA...DROPPING VSBYS TO 1 1/2SM. TEMPERATURES ARE FALLING BEHIND THE FRONT INTO THE SINGLE DIGITS AND TEENS ACROSS MANITOBA. WITH THE FRONT ARRIVING TONIGHT...SNOW CHANCES/ACCUMS AND TEMPERATURES TOMORROW ARE THE MAIN FORECAST CONCERNS. TONIGHT...A STRONG SHORTWAVE TROUGH WILL DIVE SOUTHEAST ACROSS ONTARIO...WITH THE TAIL END OF THE VORT PASSING ACROSS LAKE SUPERIOR AND THE UPPER PENINSULA. THIS SHORTWAVE WILL PUSH AN ARCTIC FRONT INTO FAR NORTH-CENTRAL WISCONSIN BY 06Z AND ACROSS THE REST OF THE FORECAST AREA OVERNIGHT. FORCING IS VERY GOOD ALONG THE FRONT...WITH STRONG CONVERGENCE...AND DECENT MID-LEVEL FGEN AND -DIVQ. MOISTURE TRANSPORT AND ISENTROPIC ASCENT AHEAD OF THE FRONT IS ON THE WEAKER SIDE THOUGH...AND THINK THE NAM MAY BE A LITTLE TOO AMBITIOUS IN GENERATING PRECIP AHEAD OF THE FRONT. BUT SHOULD SEE A BKN BAND OF PRECIP RIGHT AHEAD OF THE FRONT THOUGH. BUFKIT SOUNDINGS INDICATE THAT LOW WET BULB TEMPS SHOULD KEEP PTYPE AS MOSTLY SNOW OVER CENTRAL AND NORTHEAST WISCONSIN...WHILE PRECIP WILL LIKELY START OUT AS RAIN OVER EAST-CENTRAL WISCONSIN. THEN PRECIP WILL CHANGE TO SNOW AS COLDER AIR FILTERS SOUTH. COULD SEE A DUSTING OVER THE SOUTHEAST FORECAST AREA. MAX OMEGA WILL RESIDE IN THE DENDRITIC GROWTH ZONE...WHICH SUGGESTS THAT SNOWFALL RATES MAY BECOME BRIEFLY INTENSE WITHIN THE STRONGER SNOW SHOWERS ACROSS THE NORTH. BECAUSE THE SNOW SHOWERS WILL LIKELY BE FAST MOVING...TOUGH TO SEE MUCH MORE THAN AN INCH OF ACCUMULATION. LOWS FALLING INTO THE LOWER 20S NORTH...BUT ONLY FALLING INTO THE LOWER 30S SOUTHEAST. MONDAY...ARCTIC AIR WILL QUICKLY FLOOD SOUTHEAST ACROSS THE FORECAST AREA DURING THE MORNING...AND TEMPS WILL NOT RISE VERY MUCH OFF THE MORNING LOWS. MAY ACTUALLY SEE TEMPS FALL A BIT DURING THE MORNING OVER EAST-CENTRAL WISCONSIN. THOUGH THE AIRMASS IS VERY DRY BEHIND THE FRONT...SHOULD STILL SEE SCATTERED LAKE EFFECT SNOW SHOWERS ACROSS N-C WISCONSIN DURING THE MORNING WHICH SHOULD NOT AMOUNT TO MUCH ACCUMULATION. MAY SEE THE SNOW SHOWERS PARTIALLY DIMINISH IN THE AFTERNOON AS THE DRY AIR ASSERTS ITS INFLUENCE. A FEW LIGHT SNOW SHOWERS MAY ALSO LINGER ACROSS EAST-CENTRAL WISCONSIN EARLY IN THE MORNING RIGHT BEHIND THE FRONT. NORTHWEST WINDS WILL BE BREEZY...AND SHOULD LEAD TO APPARENT TEMPS FALLING INTO THE SINGLE DIGITS AND TEENS...DESPITE SOME SUNSHINE. MORNING HIGHS IN THE MID 20S NORTH TO MID 30S SOUTHEAST. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 230 PM CST SUN NOV 10 2013 MODELS IN GENERAL AGREEMENT ON OVERALL PATTERN CHANGE EXPECTED DURING THIS PERIOD AS WEST UPPER RIDGE/EAST TROF TRANSITIONS TO WESTERN TROF AND EASTERN RIDGE. OVERALL...LITTLE CHANGE TO THIS PERIOD. LINGERING LAKE EFFECT SNOW SHOWERS OR FLURRIES IN THE LK SUPERIOR SNOWBELT EARLY IN PERIOD...BUT WINDS BACK QUICKLY ENDING THREAT. WARM AIR ADVECTION ON BACKSIDE OF RETREATING ARCTIC RIDGE AT THE SURFACE...ENHANCED BY LIFT FROM WEAK WAVE PRODUCES A PERIOD OF LIGHT PRECIPITATION...MAINLY RAIN...LATE THU INTO EARLY FRI. AS RIDGE MOVES OFF EAST COAST...DEEPER MOISTURE INFLUX NOTED. ANOTHER WAVE IN SW FLOW PRODUCES LARGER AREA OF RAIN...CLIPPING THE EASTERN 2/3RDS OF WISCONSIN NEXT WEEKEND. SW FLOW WILL USHER IN MILDER TEMPS AFTER TUE...WITH TEMPS ABOVE NORMS BY END OF WEEK. TEMP FORECAST A BLEND OF BEST PERFORMING GUIDANCE. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 603 PM CST SUN NOV 10 2013 MID-LEVEL CLOUDS HAVE OVERSPREAD THE AREA THIS EVENING...AND WILL CONTINUE TO LOWER AS A STRONG ARCTIC COLD FRONT APPROACHES THE AREA. THIS FRONT WILL MOVE QUICKLY ACROSS THE AREA...REACHING THE WI/MI AROUND MIDNIGHT...THEN INTO THE FOX VALLEY AND LAKESHORE BY 7 AM MONDAY. RAIN AND SNOW SHOWERS WILL ACCOMPANY THE FRONT...AND SOME BRIEF BURSTS OF SNOW ARE EXPECTED OUT OF THE STRONGER SNOW SHOWERS...DROPPING CIGS/VSBYS TO IFR. OTHERWISE...MVFR CONDITIONS ARE EXPECTED. OTHER THAN A BRIEF MIX AT THE ONSET...TEMPERATURE PROFILES SUPPORT MAINLY ALL SNOW AT AUW/CWA...WHILE TEMPS LOOK COLD ENOUGH FOR ALL SNOW AT RHI. FOR GRB/ATW...ENOUGH WARM AIR NEAR THE SURFACE SHOULD ALLOW FOR THE PRECIP TO START AS RAIN...THEN AS THE FRONT MOVES THROUGH...LOOK FOR THE RAIN TO MIX WITH AND CHANGE OVER TO SNOW. THE SNOW SHOWERS WILL COME TO AN END EARLY MONDAY MORNING FROM NORTHWEST TO SOUTHEAST AS THE FRONT MOVES SOUTH OF THE AREA. THE EXCEPTION WILL BE OVER THE SNOW BELTS OF N-C WISCONSIN...AS NORTHWEST WINDS WILL GENERATE LAKE EFFECT SNOW AND CLOUDS. THINK THE SNOW WILL STAY NORTH OF RHI...HOWEVER WILL BE MORE PESSIMISTIC WITH THE CLOUD COVER AND KEEP MVFR CIGS IN PLACE. A RETURN TO VFR CONDITIONS ARE EXPECTED BY EARLY AFTERNOON AT AUW/CWA/GRB/ATW AS CLOUDS DEPART AND DRIER AIR MOVES IN. GUSTY NORTHWEST WINDS ARE EXPECTED BEHIND THE FRONT LATE TONIGHT AND ON MONDAY...WITH SOME GUSTS APPROACHING 30 KTS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........KIECKBUSCH SHORT TERM.....MPC LONG TERM......JKL AVIATION.......BERSCH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
604 PM CST SUN NOV 10 2013 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 230 PM CST SUN NOV 10 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE HIGH PRESSURE MOVING SOUTHEAST ACROSS THE MID-MISSISSIPPI VALLEY AND LOW PRESSURE DIVING SE ACROSS NORTHWEST ONTARIO. ATTACHED TO THE SURFACE LOW IS AN ARCTIC COLD FRONT WHICH IS PUSHING INTO THE NORTHERN PLAINS. LOW STRATO-CU ACROSS THE NORTH IS FINALLY EXITING NORTHEAST WISCONSIN AT THE MOMENT...BUT MID AND HIGH CLOUDS ARE ALREADY MOVING INTO THE STATE. AS A RESULT...CLOUDS WILL BE ON THE INCREASE FOR THE REST OF THE AFTERNOON. BUT QUICKLY ATTENTION WILL TURN TO THE ARCTIC FRONT. SNOW SHOWERS ARE OCCURRING ALONG THE FRONT OVER SOUTHWEST ONTARIO AND FAR NORTHERN MINNESOTA...DROPPING VSBYS TO 1 1/2SM. TEMPERATURES ARE FALLING BEHIND THE FRONT INTO THE SINGLE DIGITS AND TEENS ACROSS MANITOBA. WITH THE FRONT ARRIVING TONIGHT...SNOW CHANCES/ACCUMS AND TEMPERATURES TOMORROW ARE THE MAIN FORECAST CONCERNS. TONIGHT...A STRONG SHORTWAVE TROUGH WILL DIVE SOUTHEAST ACROSS ONTARIO...WITH THE TAIL END OF THE VORT PASSING ACROSS LAKE SUPERIOR AND THE UPPER PENINSULA. THIS SHORTWAVE WILL PUSH AN ARCTIC FRONT INTO FAR NORTH-CENTRAL WISCONSIN BY 06Z AND ACROSS THE REST OF THE FORECAST AREA OVERNIGHT. FORCING IS VERY GOOD ALONG THE FRONT...WITH STRONG CONVERGENCE...AND DECENT MID-LEVEL FGEN AND -DIVQ. MOISTURE TRANSPORT AND ISENTROPIC ASCENT AHEAD OF THE FRONT IS ON THE WEAKER SIDE THOUGH...AND THINK THE NAM MAY BE A LITTLE TOO AMBITIOUS IN GENERATING PRECIP AHEAD OF THE FRONT. BUT SHOULD SEE A BKN BAND OF PRECIP RIGHT AHEAD OF THE FRONT THOUGH. BUFKIT SOUNDINGS INDICATE THAT LOW WET BULB TEMPS SHOULD KEEP PTYPE AS MOSTLY SNOW OVER CENTRAL AND NORTHEAST WISCONSIN...WHILE PRECIP WILL LIKELY START OUT AS RAIN OVER EAST-CENTRAL WISCONSIN. THEN PRECIP WILL CHANGE TO SNOW AS COLDER AIR FILTERS SOUTH. COULD SEE A DUSTING OVER THE SOUTHEAST FORECAST AREA. MAX OMEGA WILL RESIDE IN THE DENDRITIC GROWTH ZONE...WHICH SUGGESTS THAT SNOWFALL RATES MAY BECOME BRIEFLY INTENSE WITHIN THE STRONGER SNOW SHOWERS ACROSS THE NORTH. BECAUSE THE SNOW SHOWERS WILL LIKELY BE FAST MOVING...TOUGH TO SEE MUCH MORE THAN AN INCH OF ACCUMULATION. LOWS FALLING INTO THE LOWER 20S NORTH...BUT ONLY FALLING INTO THE LOWER 30S SOUTHEAST. MONDAY...ARCTIC AIR WILL QUICKLY FLOOD SOUTHEAST ACROSS THE FORECAST AREA DURING THE MORNING...AND TEMPS WILL NOT RISE VERY MUCH OFF THE MORNING LOWS. MAY ACTUALLY SEE TEMPS FALL A BIT DURING THE MORNING OVER EAST-CENTRAL WISCONSIN. THOUGH THE AIRMASS IS VERY DRY BEHIND THE FRONT...SHOULD STILL SEE SCATTERED LAKE EFFECT SNOW SHOWERS ACROSS N-C WISCONSIN DURING THE MORNING WHICH SHOULD NOT AMOUNT TO MUCH ACCUMULATION. MAY SEE THE SNOW SHOWERS PARTIALLY DIMINISH IN THE AFTERNOON AS THE DRY AIR ASSERTS ITS INFLUENCE. A FEW LIGHT SNOW SHOWERS MAY ALSO LINGER ACROSS EAST-CENTRAL WISCONSIN EARLY IN THE MORNING RIGHT BEHIND THE FRONT. NORTHWEST WINDS WILL BE BREEZY...AND SHOULD LEAD TO APPARENT TEMPS FALLING INTO THE SINGLE DIGITS AND TEENS...DESPITE SOME SUNSHINE. MORNING HIGHS IN THE MID 20S NORTH TO MID 30S SOUTHEAST. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 230 PM CST SUN NOV 10 2013 MODELS IN GENERAL AGREEMENT ON OVERALL PATTERN CHANGE EXPECTED DURING THIS PERIOD AS WEST UPPER RIDGE/EAST TROF TRANSITIONS TO WESTERN TROF AND EASTERN RIDGE. OVERALL...LITTLE CHANGE TO THIS PERIOD. LINGERING LAKE EFFECT SNOW SHOWERS OR FLURRIES IN THE LK SUPERIOR SNOWBELT EARLY IN PERIOD...BUT WINDS BACK QUICKLY ENDING THREAT. WARM AIR ADVECTION ON BACKSIDE OF RETREATING ARCTIC RIDGE AT THE SURFACE...ENHANCED BY LIFT FROM WEAK WAVE PRODUCES A PERIOD OF LIGHT PRECIPITATION...MAINLY RAIN...LATE THU INTO EARLY FRI. AS RIDGE MOVES OFF EAST COAST...DEEPER MOISTURE INFLUX NOTED. ANOTHER WAVE IN SW FLOW PRODUCES LARGER AREA OF RAIN...CLIPPING THE EASTERN 2/3RDS OF WISCONSIN NEXT WEEKEND. SW FLOW WILL USHER IN MILDER TEMPS AFTER TUE...WITH TEMPS ABOVE NORMS BY END OF WEEK. TEMP FORECAST A BLEND OF BEST PERFORMING GUIDANCE. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 603 PM CST SUN NOV 10 2013 MID-LEVEL CLOUDS HAVE OVERSPREAD THE AREA THIS EVENING...AND WILL CONTINUE TO LOWER AS A STRONG ARCTIC COLD FRONT APPROACHES THE AREA. THIS FRONT WILL MOVE QUICKLY ACROSS THE AREA...REACHING THE WI/MI AROUND MIDNIGHT...THEN INTO THE FOX VALLEY AND LAKESHORE BY 7 AM MONDAY. RAIN AND SNOW SHOWERS WILL ACCOMPANY THE FRONT...AND SOME BRIEF BURSTS OF SNOW ARE EXPECTED OUT OF THE STRONGER SNOW SHOWERS...DROPPING CIGS/VSBYS TO IFR. OTHERWISE...MVFR CONDITIONS ARE EXPECTED. OTHER THAN A BRIEF MIX AT THE ONSET...TEMPERATURE PROFILES SUPPORT MAINLY ALL SNOW AT AUW/CWA...WHILE TEMPS LOOK COLD ENOUGH FOR ALL SNOW AT RHI. FOR GRB/ATW...ENOUGH WARM AIR NEAR THE SURFACE SHOULD ALLOW FOR THE PRECIP TO START AS RAIN...THEN AS THE FRONT MOVES THROUGH...LOOK FOR THE RAIN TO MIX WITH AND CHANGE OVER TO SNOW. THE SNOW SHOWERS WILL COME TO AN END EARLY MONDAY MORNING FROM NORTHWEST TO SOUTHEAST AS THE FRONT MOVES SOUTH OF THE AREA. THE EXCEPTION WILL BE OVER THE SNOW BELTS OF N-C WISCONSIN...AS NORTHWEST WINDS WILL GENERATE LAKE EFFECT SNOW AND CLOUDS. THINK THE SNOW WILL STAY NORTH OF RHI...HOWEVER WILL BE MORE PESSIMISTIC WITH THE CLOUD COVER AND KEEP MVFR CIGS IN PLACE. A RETURN TO VFR CONDITIONS ARE EXPECTED BY EARLY AFTERNOON AT AUW/CWA/GRB/ATW AS CLOUDS DEPART AND DRIER AIR MOVES IN. GUSTY NORTHWEST WINDS ARE EXPECTED BEHIND THE FRONT LATE TONIGHT AND ON MONDAY...WITH SOME GUSTS APPROACHING 30 KTS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......JKL AVIATION.......BERSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
345 PM CST SAT NOV 9 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 343 PM CST SAT NOV 9 2013 AT 3 PM...A SHORT WAVE TROUGH WAS MOVING ACROSS SOUTHEAST MINNESOTA AND WESTERN WISCONSIN. THE LATEST RUC SHOWS THAT THERE WILL BE ANOTHER SURGE SOUTHWARD OF 850 TO 925 MB MOISTURE. THIS MOISTURE IS TRAPPED BELOW AN INVERSION AT 800 MB THROUGH THE EARLY OVERNIGHT AND THEN THIS INVERSION LOWERS AS AN UPPER LEVEL RIDGE PRODUCES ENOUGH SUBSIDENCE THAT THE DRY AIR ABOVE THE INVERSION IS ABLE TO MIX OUT ANY RESIDUAL MOISTURE IN THIS LAYER. HOWEVER LOOKING AT THE SATELLITE LOOP...THERE ARE CURRENTLY HOLES AT THE SOUTHERN EXTENT OF THIS MOISTURE AND THIS WILL AFFECT AREAS ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR. AS A RESULT...NOT QUITE AS CERTAIN WITH THE CLOUD FORECAST IN THE AREA TONIGHT. HOWEVER WITH DARKNESS NOT THAT FAR AWAY...DECIDED TO FOLLOW THE RUC JUST IN CASE THE CURRENT MOISTURE THAT IS OUT THERE CAN SPREAD BELOW THE INVERSION. MEANWHILE AREAS NORTH OF THE INTERSTATE 94 CORRIDOR...THE CLOUD FORECAST IS MORE CERTAIN AND IT LOOKS LIKE THIS AREA WILL REMAIN CLOUDY THROUGH AT LEAST 3 AM SUNDAY. IN ADDITION TO THE CLOUDS LATE THIS AFTERNOON AND EVENING...THE AREA WILL HAVE TO CONTEND WITH VERY GUSTY WINDS AS THE 925 TO 850 LAPSE RATES BECOME VERY STEEP. WINDS WILL GUST UP TO 40 MPH AT TIMES ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA. ON SUNDAY AFTERNOON...THE CLOUDS WILL RAPIDLY INCREASE AHEAD OF AN APPROACHING SHORT WAVE TROUGH. MODERATE WARM AIR ADVECTION AHEAD OF THIS WAVE WILL ALLOW TEMPERATURES TO WARM INTO THE LOWER AND MID 40S. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 343 PM CST SAT NOV 9 2013 ON SUNDAY NIGHT...A STRONG SHORT WAVE MOVES SOUTHEAST ACROSS ONTARIO AND INTO WESTERN UPPER MICHIGAN. STRONG 800 TO 600 MB FRONTOGENETIC FORCING AND 280-290K ISENTROPIC LIFT AHEAD OF THIS WAVE WILL QUICKLY SATURATE THE AIR MASS ALONG AND AHEAD OF THE ARCTIC COLD FRONT. THE HIGHEST PRECIPITATION PROBABILITIES WILL BE FOUND ALONG AND NORTH OF THE INTERSTATE 94 CORRIDOR WHERE THE 280-290K CONDENSATION PRESSURE DEFICITS ARE LESS THAN 30 MB. PRECIPITATION AMOUNTS WILL BE UP TO 5 HUNDREDTHS OF AN INCH. SOUNDINGS SUGGEST THAT THE PRECIPITATION WILL INITIALLY START OUT AS RAIN AND THEN TRANSITION OVER TO SNOW. THERE MAY BE EVEN A BRIEF PERIOD OF SLEET. SNOW ACCUMULATIONS WILL RANGE FROM A TRACE TO A COUPLE OF TENTHS OF AN INCH. ICE ACCUMULATIONS WILL BE JUST A TRACE. ON MONDAY MORNING...THE ARCTIC FRONT CONTINUES TO MOVE QUICKLY SOUTHEAST ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. THE 280-290K CONDENSATION PRESSURE DEFICITS DROP TO LESS THAN 30 MB ALONG AND SOUTH OF THE INTERSTATE 90 CORRIDOR. HOWEVER BY THIS TIME...THE QPF AMOUNTS ARE RUNNING AROUND A HUNDREDTH OF AN INCH. LIKE IN NORTH-CENTRAL WISCONSIN...THE PRECIPITATION WILL LIKELY START OUT AS RAIN AND THEN QUICKLY TRANSITION OVER TO SNOW. SNOW ACCUMULATIONS WILL RANGE FROM A TRACE TO A TENTH OF AN INCH. THERE MAY BE A BRIEF PERIOD OF SLEET...BUT NO ACCUMULATIONS ARE EXPECTED. FROM LATE SUNDAY NIGHT INTO MONDAY EVENING...THERE WILL BE STRONG COLD AIR ADEVCTION. SINCE THE CONSRAW TENDS TO HANDLE THESE SITUATIONS THE BEST...WENT WITH IT FOR POPULATING THE HOURLY TEMPERATURES AND DEW POINTS. TEMPERATURES WILL FALL THROUGH THE 20S AND LOWER 30S DURING THE MORNING...AND THEN STABILIZE AND RISE A FEW DEGREES DURING THE AFTERNOON. ON MONDAY NIGHT...TEMPERATURES WILL FALL INTO THE 10 TO 20 DEGREE RANGE. THIS WILL BE THE COLDEST AIR MASS OF THE SEASON AND 10 TO 15 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. IF IT WAS NOT FOR THE LACK OF MEASURABLE SNOW ON THE GROUND AND WINDS REMAINING AROUND 10 MPH...TEMPERATURES WOULD BE EVEN COLDER. WIND CHILLS ON TUESDAY MORNING WILL BE IN THE SINGLE DIGITS. ON TUESDAY...850 MB TEMPERATURE ANOMALIES RANGE FROM 1.5 TO 2 STANDARD DEVIATIONS BELOW NORMAL. THIS WILL KEEP TEMPERATURES WELL BELOW NORMAL. HIGH TEMPERATURES WILL RANGE FROM 25 TO 30 ALONG AND NORTH OF INTERSTATE 90 AND IN THE LOWER 30S ACROSS THE REMAINDER OF THE AREA. HIGH TEMPERATURES ARE NORMALLY IN THE MID 40S FOR THIS TIME OF YEAR. FROM TUESDAY NIGHT INTO WEDNESDAY...STRONG WARM AIR ADVECTION DEVELOPS ACROSS THE AREA AS A SHORT WAVE TROUGH APPROACHES THE REGION FROM THE CENTRAL PLAINS. BOTH 925 TO 850 MB TEMPERATURES WARM ANYWHERE FROM 6 TO 8C. PRIOR TO THE ARRIVAL OF THE WARM AIR ADVECTION... TEMPERATURES WILL QUICKLY FALL INTO THE TEENS TUESDAY EVENING... AND THEN STABILIZE OVERNIGHT AS THE WINDS BECOME SOUTHWESTERLY. HIGH TEMPERATURES ON WEDNESDAY WILL RANGE FROM THE MID 30S TO LOWER 40S. FROM WEDNESDAY NIGHT INTO THURSDAY...A SHORT WAVE TROUGH WILL MOVE EAST THROUGH THE FORECAST AREA. WITH QUITE A BIT OF DRY AIR AHEAD OF THIS SYSTEM...IT WILL TAKE AWHILE TO SATURATE. THE 280-290K CONDENSATION PRESSURE DEFICITS DO NOT FALL TO LESS THAN 30 MB UNTIL THIS SYSTEM GETS INTO NORTHEAST IOWA AND CENTRAL AND SOUTHWEST WISCONSIN. AS A RESULT...DID NOT INCLUDE ANY SMALL PRECIPITATION CHANCES UNTIL IT MOVED INTO THIS AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1100 AM CST SAT NOV 9 2013 PROBLEMATIC CIG FORECAST. LATEST SATELLITE AND SFC OBS POINT TO A BROAD EXPANSE OF MOSTLY MVFR CIGS EXTENDING FROM THE UPPER MISSISSIPPI RIVER VALLEY ACROSS ND...ASSOCIATED WITH A LOW TRACKING EAST ACROSS THE NORTHERN GREAT LAKES. NAM/GFS SUGGEST THAT SUBSIDENCE AND MIXING DOWN OF DRIER MID LEVEL AIR WILL ERODE THE SOUTHERN FLANK OF THE LOW STRATUS...RESULTING IN CLEARING SKIES AT KRST/KLSE BY MID TO LATE AFTERNOON. THE RAP IS QUITE DIFFERENT...HOLDING ONTO THIS LOW SATURATION THROUGH MUCH OF THE EVENING. ALL THE MODELS HOLD ONTO A 850-800 MB INVERSION THROUGH SUNDAY AFTERNOON...SO IF THE MOISTURE REMAINS TRAPPED...CLOUDS AND THE MVFR CIGS COULD HANG AROUND TODAY/TONIGHT. MODELS ARE ALL DOING A DECENT JOB DEPICTING WHERE THE CLOUDS ARE CURRENTLY. GOING TO STEER THE TAFS TOWARD THE PESSIMISTIC SIDE. MODELS HAVE A TENDENCY TO CLEAR CLOUDS A BIT TOO FAST IN FALL/WINTER...AND THIS MIGHT BE THE CASE HERE. IF MIXING BECOMES EVIDENT...WITH CLOUDS ERODING...TAFS WILL NEED TO BE UPDATED FOR THE QUICKER CLEARING TREND. AS FOR WINDS...TIGHT PRESSURE GRADIENT WILL KEEP THEM RELATIVELY STRONG/GUSTY INTO THE EARLY EVENING HOURS. HIGH PRESSURE IS SLATED TO BUILD IN FROM THE NORTHERN PLAINS SUNDAY MORNING...SO LOOK FOR DECREASING WINDS OVERNIGHT...WITH A SHIFT TO SOUTHWEST SUNDAY AFTERNOON. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION.....RIECK
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 300 PM CST SAT NOV 9 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE MOVING EAST ACROSS LAKE SUPERIOR EARLY THIS AFTERNOON. WINDS ARE VEERING AROUND TO THE WEST BEHIND THE LOW AND FLOODING THE REGION WITH WIDESPREAD LOW STRATUS. LIGHT RAIN/DRIZZLE AND SNOW WERE OBSERVED ACROSS NORTHERN WISCONSIN EARLIER TODAY...BUT HAVE NOT SEEN AN OB WITH PRECIP IN IT OVER THE PAST HOUR. WIND GUSTS HAVE BEEN STEADILY INCREASING THROUGH THE DAY...AND HAVE OBSERVED A FEW GUSTS REACHING 34 TO 35 KNOTS. WITH COLD ADVECTION ONGOING AND THE PRESSURE GRADIENT TIGHTENING...SHOULD SEE THE GUSTINESS CONTINUE INTO THE EVENING HOURS. THE WIND GUSTS AND LIGHT PRECIP ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM. TONIGHT...LOW PRESSURE WILL MOVE EAST ACROSS EASTERN LAKE SUPERIOR AND SOUTHEAST ONTARIO THIS EVENING AND INTO QUEBEC OVERNIGHT. TO THE WEST OF THE LOW...THE LOW LEVEL PRESSURE GRADIENT WILL TIGHTEN AS VEERING WINDS TO THE NORTHWEST COLD ADVECTS THROUGH THE NIGHT. THOUGH SOME SURFACE STABILIZATION SHOULD TAKE PLACE...MARGINALLY STEEP LOW LEVEL LAPSE RATES WILL MAINTAIN STRONG GUSTY WINDS THROUGH THE EVENING WITH SOME GUSTS UP TO 35 TO 40 MPH POSSIBLE. LOOKING AT PROGGED SOUNDINGS...THEY SHOW DECREASING SATURATION IN THE LOW LEVELS THROUGH THE EVENING...WHICH SUGGESTS CLEARING WILL TAKE PLACE OVER CENTRAL AND NORTHEAST WISCONSIN. THINK THIS IS CONSIDERABLY TOO OPTIMISTIC...BASED ON SATELLITE TRENDS BUT ALSO ON THERMAL TROUGHING AND VEERING FLOW OFF LAKE SUPERIOR...WHICH SHOULD KEEP CLOUDS AROUND LONGER. SO INCREASED CLOUD COVER TONIGHT THROUGH 12Z. CONDITIONS BECOME MARGINALLY SUPPORTIVE FOR LAKE EFFECT SNOW BY MID TO LATE EVENING OVER THE SNOW BELTS OF N-C WISCONSIN SO INCREASED POPS INTO THE LIKELY RANGE. DELTA T/S ARE ONLY AROUND 13-14C...SO NOT EXPECTING MUCH ACCUMULATIONS...PERHAPS AN INCH OVER NORTHERN VILAS. LOWS IN THE UPPER 20S TO THE LOWER 30S. SUNDAY...SURFACE HIGH PRESSURE WILL BE BUILDING INTO THE REGION DURING THE MORNING AND MOVING ACROSS THE AREA DURING THE AFTERNOON. WITH BACKING WINDS AND A WARMING THERMAL PROFILE...SHOULD SEE CLOUDS ERODING PRETTY QUICKLY DURING THE MORNING. THEN A MID AND HIGH DECK SHOULD INCREASE CLOUDS ONCE AGAIN IN THE AFTERNOON. HIGHS IN THE UPPER 30S NORTH TO MID 40S SOUTH. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 300 PM CST SAT NOV 9 2013 AN ARCTIC COLD FRONT WILL MOVE THROUGH THE REGION SUNDAY NIGHT AND BRING THE COLDEST AIR OF THE SEASON. A 125KT JET AT 300MB COMBINED WITH LOW LEVEL CONVERGENCE AND WARM ADVECTION AHEAD OF THE FRONT SHOULD BE SUFFICIENT TO PRODUCE A DECENT AREA OF SNOW SHOWERS. THE UPSTREAM LAKES ARE NOT FROZEN YET AND IT SEEMS LIKE THEY CONTRIBUTE QUITE A BIT OF MOISTURE WITH ARCTIC AIR OUTBREAKS EARLY IN THE SEASON. SO THERE COULD BE AT LEAST A DUSTING OF SNOW ACROSS THE ENTIRE FORECAST AREA. THEN DRY AND MUCH COLDER MONDAY THROUGH THURSDAY WITH TEMPERATURES WELL BELOW NORMAL. LAKE EFFECT SNOW IS LIKELY IN FAR NORTHCENTRAL WISCONSIN MONDAY THROUGH TUESDAY. INSTABILITY IS MODERATE TO EXTREME AND WINDS ARE FAVORABLE AT TIMES. THE MAIN THING WORKING AGAINST A BIG EVENT IS THE DRYNESS OF THE AIR AND ALSO SUBSIDENCE. THINK THERE WILL BE SEVERAL INCHES OVER THE COURSE OF THE TWO DAYS IN VILAS COUNTY. IT WILL BECOME MILDER TOWARDS THE END OF THE WEEK AS THE CENTER OF THE COLD AIR PASSES BY AND WINDS BECOME SOUTHERLY AHEAD OF THE NEXT SYSTEM. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1137 AM CST SAT NOV 9 2013 LOW PRESSURE WILL BE MOVING AWAY FROM THE REGION TO THE EAST OVER THE TAF PERIOD. WINDS WILL VEER TO THE NORTHWEST...AND BRING IN COLDER AIR AND AMPLE CLOUD COVER FROM THE NORTHERN PLAINS. LIGHT RAIN AND DRIZZLE WILL MIX WITH AND CHANGE OVER TO SNOW ACROSS NORTHERN WISCONSIN THIS AFTERNOON...BEFORE BECOMING MORE LAKE EFFECT BASED TONIGHT. GENERALLY...MVFR CIGS CAN BE EXPECTED UNTIL LATE TONIGHT WHEN WILL START TO SEE CLEARING OVER CENTRAL AND NORTHEAST WISCONSIN. WITHIN THE PRECIP OVER NORTH-CENTRAL WISCONSIN...LOCAL IFR CIGS/VSBYS WILL BE POSSIBLE. THE PRECIP IS NOT EXPECTED TO DIMINISH UNTIL TOMORROW MORNING WHEN IMPROVING CONDITIONS SHOULD OCCUR. WEST TO NORTHWEST WINDS WILL ALSO BECOME VERY GUSTY THIS AFTERNOON AND EVENING...WITH ISOLATED GUSTS UP TO 35 KTS POSSIBLE. WINDS WILL GRADUALLY DIMINISH IN THE EVENING AND OVERNIGHT. && .MARINE... ISSUED AT 300 PM CST SAT NOV 9 2013 THE LATEST 12Z DATA IS SHOWING WINDS INCREASING AT 900MB TONIGHT INTO THE 40-45 KNOT RANGE AS WINDS VEER AROUND TO THE NORTHWEST DIRECTION. THIS TRAJECTORY IS SUPPORTIVE OF GALES OVER THE BAY OF GREEN BAY AND NEARSHORE WATERS OF LAKE MICHIGAN ADJACENT TO DOOR COUNTY. SO WITH COORDINATION FROM MQT...UPGRADED TO A GALE WARNING. SOME DISCUSSION OF UPGRADING TO GALES FARTHER SOUTH...BUT OFFSHORE WINDS AND SOME STABILIZATION OF THE BOUNDARY LAYER TONIGHT SUGGESTS THE HIGHER END GUSTS WILL OCCUR MORE TOWARDS OPEN LAKE THAN THE NEARSHORE WATERS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......MPC MARINE.........MPC
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1144 AM CST SAT NOV 9 2013 .UPDATE... A FEW ADJUSTMENTS WERE MADE TO THE TODAY PERIOD. A LARGE SWATH OF CLOUDS COVER THE UPPER MIDWEST AND WESTERN GREAT LAKES ASSOCIATED WITH A SFC LOW AND UPPER LEVEL SHORTWAVE TROUGH TRAVERSING THE AREA. THE LOW IS CURRENTLY OVER CENTRAL LAKE SUPERIOR AND IS GRADUALLY MOVING EAST. SKY COVER WAS INCREASED...ESPECIALLY IN THE NORTHEAST HALF OF THE FORECAST AREA THIS AFTERNOON. GOES/R PG NSSL WRF ABI SYNTHETIC SAT IMAGERY HAS A FAIR HANDLE ON MOST OF THE CLOUD COVER. IMAGERY SHOWS THE CLOUD COVER SLOWLY RECEDING TO THE NORTHEAST LATER DAY. JUXTAPOSED WITH MODEL RH AND RAP PROXIMITY SOUNDINGS...THIS DOESNT SEEM TOO UNREASONABLE. HOWEVER...THE ABI FORECAST LOOKS TO BE A TAD TOO QUICK GIVEN THE DECENT MOISTURE THAT THE MODELS AND RAP13 HOLD ON TO AT THE LOW LEVELS THIS AFTERNOON. ESPECIALLY CONSIDERING THE LATEST TRENDS VIA VIS SATELLITE AND WHAT IS UPSTREAM. OTHERWISE...GUSTY CONDITIONS CONTINUE TODAY. VERY IMPRESSIVE SURFACE PRESSURE GRADIENT AND DECENT WINDS ALOFT...WITH MEAN 1000-850 HPA WINDS AROUND 35 KTS. WIND GUSTS UP TO 30 KTS SHOULD BE REALIZED AT THE SFC...GIVEN ADEQUATE MIXING/MOMENTUM TRANSFER INTO THE BOUNDARY LAYER. ET && .AVIATION/18Z TAFS/... DAYTIME HEATING SHOULD SLOWLY MIX OUT OVERCAST VFR DECK TO BROKEN THIS AFTERNOON. MVFR CEILINGS UPSTREAM OVER WESTERN WISCONSIN MAY OCCUR AT TAF SITES...THOUGH DAYTIME HEATING SHOULD HELP THESE CEILINGS MIX UP TO VFR CATEGORY AS THEY MOVE INTO THE AREA. GUSTY WEST NORTHWEST WINDS ARE EXPECTED THIS AFTERNOON AS WELL...WITH GUSTS TO AROUND 30 KNOTS POSSIBLE AT TIMES. WINDS WILL REMAIN GUSTY AND VEER NORTHWESTERLY TONIGHT...WITH GUSTS UP TO AROUND 30 KNOTS STILL POSSIBLE. VFR CEILINGS SHOULD LINGER THROUGH THE EVENING AND POSSIBLY LATER TONIGHT...BEFORE MOVING OUT OF THE EASTERN SITES BY 12Z SUNDAY AT THE LATEST. NORTHWEST WINDS WILL GRADUALLY DIMINISH AND BACK TO THE WEST AND SOUTHWEST ON SUNDAY...AS HIGH PRESSURE REMAINS SOUTHWEST OF THE AREA. FEW TO SCATTERED STRATOCUMULUS CLOUDS ARE EXPECTED. WOOD && .MARINE... SMALL CRAFT ADVISORY CONTINUES UNTIL 12Z SUNDAY ACROSS THE NEARSHORE WATERS OF LAKE MICHIGAN. TIGHT PRESSURE GRADIENT FROM PASSING LOW PRESSURE TO THE NORTH AND HIGH PRESSURE TO THE WEST WILL REMAIN ACROSS THE AREA THIS AFTERNOON AND TONIGHT. WEST NORTHWEST GUSTS TO 30 KNOTS ARE EXPECTED THIS AFTERNOON...BECOMING NORTHWEST TONIGHT...WITH A FEW GUSTS TO 35 KNOT GALES. WINDS AT 1000 FEET ABOVE THE SURFACE ARE AROUND 35 KNOTS DURING THIS TIME...WHICH MAY MIX DOWN AT TIMES. NOT SURE IF THEY WILL BE FREQUENT ENOUGH FOR A GALE WARNING. WILL KEEP WATCH AND DECIDE WITH THE AFTERNOON FORECAST ISSUANCE. THE PRESSURE GRADIENT GRADUALLY WEAKENS SUNDAY...AS HIGH PRESSURE MOVES SOUTHWEST OF THE AREA. THE SMALL CRAFT ADVISORY MAY NEED TO BE EXTENDED A FEW HOURS ON SUNDAY...UNTIL THE GUSTS SUBSIDE BELOW 22 KNOTS. WOOD && .PREV DISCUSSION... /ISSUED 338 AM CST SAT NOV 9 2013/ SHORT TERM... TODAY-FORECAST CONFIDENCE HIGH IMPRESSIVE PV1.5 CENTER BELOW 500 MB NEAR GRB CURRENTLY AND PULLING AWAY RAPIDLY THIS MORNING. SUBSIDENCE KICKING IN AND EVEN BRIEF CLEARING BEFORE COLD ADVECTION MIXING CLOUDS MOVE IN THIS MORNING. RAP13 TAKES SECOND SUB 500MB PV1.5 CENTER FROM NORTH DAKOTA CURRENTLY ACROSS CENTRAL WISCONSIN BY MIDDAY. MODELS HOLD ONTO DECENT MOISTURE AROUND 3000FT THROUGH AT LEAST MID AFTERNOON AND LIKELY INTO THE EVENING. A TAD OF CAPE SHOWN BUT VERY STRONG INVERSION IN 850-800 MB LAYER SHOULD RESULT IN CONVECTION SPREADING OUT A FAIRLY LOW LEVEL. MOISTURE STAYS BELOW -5C SO LIMITED POTENTIAL FOR SPRINKLES FLURRIES SO WILL LEAVE IT DRY DESPITE SOME HINTS FROM 4KM MODELS OF THAT POTENTIAL MAINLY IN THE FAR NORTH. WILL BE COLD ADVECTING ALL DAY BUT 925 MB TEMPS UP AROUND +5C SUGGEST UPPER 40S TO LOWER 50S BY MIDDAY BEFORE TEMPERATURES DROP OFF. ECMWF MOS HAS MIDDLE 50S AND THAT IS NOT IMPOSSIBLE BUT LOW CLOUDS WILL MAKE IT TOUGH. TONIGHT-FORECAST CONFIDENCE HIGH 1030MB HIGH SETTLES INTO IOWA BY MORNING. NORTHWEST GRADIENT REMAINS FRESH ALL NIGHT SO NOT PARTICULARLY GOOD RADIATION CONDITIONS. COLD ADVECTION WILL HELP DROP TEMPERATURES BUT READINGS WILL ONLY GET DOWN AROUND 30F DUE TO DECENT MIXING AND LINGERING LOW CLOUDS. SUNDAY AND SUNDAY NIGHT...MEDIUM TO HIGH. SUNSHINE ON SUNDAY AND LATE AFTERNOON WARM AIR ADVECTION /WAA/ WILL HELP TEMPS WARM INTO THE MID TO POSSIBLY UPPER 40S. STEADY WAA SUNDAY NIGHT WILL KEEP TEMPS MILD. HIGH CLOUDS WILL BE MOVING IN DURING THE AFTERNOON AND OVERNIGHT. ANY LIGHT RAIN THAT DEVELOPS IN THE WAA THROUGH SUNDAY EVENING SHOULD REMAIN NORTH OF THE MKX FORECAST AREA. AFTER MIDNIGHT...MODEL DISCREPANCIES LEAD TO THE MENTION OF RAIN OR SNOW IN NORTHERN MKX FCST AREA. THE GFS AND UKMET CONTINUE TO HAVE A FASTER SURFACE COLD FRONTAL PASSAGE THROUGH SOUTHEAST WI THAN THE NAM...ECMWF AND CANADIAN MODELS. WPC PREFERS A NON-GFS SOLUTION SO STEERED AWAY FROM IT AS MUCH AS POSSIBLE. THERE IS A SMALL POSSIBILITY THAT SOME WAA PRECIP COULD TRANSLATE SOUTHEASTWARD OVERNIGHT...THUS KEPT THE SMALL POPS IN THE FCST. PRECIP TYPE WOULD BE RAIN IF IT/S WAA-RELATED AND SNOW IF IT/S COLD FRONT-RELATED. LONG TERM... MONDAY...FORECAST CONFIDENCE MEDIUM. A STRONG UPPER LEVEL LOW PRESSURE TROUGH WILL DROP DOWN THROUGH THE GREAT LAKES REGION EARLY NEXT WEEK...PUSHING A STRONG COLD FRONT THROUGH SOUTHERN WI MONDAY MORNING AND SOUTHEASTWARD TO THE MID ATLANTIC STATES THEREAFTER. SOME MODELS SUGGEST PRECIP WILL ARRIVE JUST BEHIND THE SURFACE FRONT THROUGH SOUTHERN WI WHILE OTHERS REMAIN DRY. THERE IS STRONGER OMEGA POST-FRONTAL WITH SLOPED FRONTOGENETIC FORCING AND DCVA WITH A SHORT WAVE TROUGH. MODEL SOUNDINGS SHOW A DRY LAYER BELOW 850MB THAT COULD LIMIT AREAL COVERAGE OF PRECIP. LOW TEMPS MON NIGHT WILL ROUGHLY BE THE HIGH TEMPS TUE IN THE NORTHWEST MKX FORECAST AREA. SOUTHEAST WI WILL LIKELY HAVE AN OPPORTUNITY TO WARM INTO THE LOWER 40S BEFORE THE COLD FRONT ARRIVES LATER IN THE MORNING. IF ALL THE PRECIP IS POST FRONTAL...THEN MODEL TEMP PROFILES SUPPORT ALL SNOW. IF IT IS ALONG THE FRONT...THEN EXPECT A RAIN CHANGING OVER TO SNOW AS THE COLUMN SATURATES AND COOLS. THE ECMWF IS SLOWEST TO END THE PRECIP FROM NORTHWEST TO SOUTHEAST SO KEPT POPS IN THROUGH THE AFTERNOON. LOTS OF UNCERTAINTY IN PRECIP END TIME. MONDAY NIGHT AND TUESDAY...FORECAST CONFIDENCE HIGH. THE COLD AIR MASS WILL SETTLE IN BEHIND THE COLD FRONT MONDAY NIGHT AND TUESDAY. 925MB TEMPS WILL DROP TO -10C OVERNIGHT AS SKIES CLEAR...ALLOWING LOWEST TEMPS OF THE SEASON SO FAR...IN THE UPPER TEENS INLAND FROM THE LAKE. 925MB TEMPS WILL ONLY RECOVER TO -8C BY LATE AFTERNOON...WHICH SUPPORTS HIGH TEMPS ONLY IN THE UPPER 20S ON TUESDAY...DESPITE SUNSHINE. NORTHWEST WINDS WILL BE SLOW TO COME DOWN...SO IT WILL FEEL QUITE COLD. WEDNESDAY THROUGH FRIDAY...FORECAST CONFIDENCE HIGH. TEMPERATURES WILL GRADUALLY RECOVER AS SOUTHWEST WINDS RETURN TO THE REGION AS HIGH PRESSURE MOVES OFF TO THE EAST AND ANOTHER LOW PRESSURE TROUGH APPROACHES. A WEAK SURFACE AND UPPER LEVEL TROUGH ARE EXPECTED TO SWING THROUGH WI ON THU AND COULD BRING SOME LIGHT RAIN WITH IT. LATEST MODEL RUNS HAVE MORE AGREEMENT WITH LIGHT QPF...SO EXPECT INCREASING POPS FOR THU WITH LATER FORECASTS. THAT UPPER TROUGH WILL TAKE A WHILE TO MOVE OUT...BUT ANY PRECIP SHOULD REMAIN NORTH OF SOUTHERN WI FOR THE REMAINDER OF THE WEEK. AVIATION/12Z TAFS/... COLD FRONT MOVING THROUGH WILL TURN WINDS TO THE WEST TODAY AND THEN NORTHWEST TONIGHT. BROKEN VFR LOW CLOUDS LOOK TO BE THE RULE TODAY BUT COULD BE A PERIOD OF MVFR THIS MORNING AS BATCH FROM NORTHEAST IOWA INTO SOUTHEAST MINNESOTA MOVES EAST. SOME UNCERTAINTY ON HOW LONG CLOUDS HOLD IN. NAM SCATTERS THINGS OUT BY 21Z WHILE GFS HOLDS ON THROUGH 03Z. WILL LEAN TOWARD SLOWER GFS AS COLD AIR STRATOCUMULUS CAN BE STUBBORN IN THESE SITUATIONS. MARINE... GALES ARE SUBSIDING BUT WILL STILL GUST TO AROUND 30 KNOTS. COORDINATED WITH GRB AND LOT AND WILL END GALE AT NEXT NEAR SHORE UPDATE AND GO WITH SMALL CRAFT ADVISORY THROUGH 6 AM SUNDAY. FLOW IS GRADUALLY TURNING TOWARD THE WEST AND SHOULD EVENTUALLY BECOME NORTHWEST TONIGHT. WAVES DRIVEN BY SOUTH WINDS SHOULD GRADUALLY SUBSIDE IN THE NEARSHORE WATERS WITH OFFSHORE FLOW THROUGH TONIGHT BUT WILL REMAIN HIGH OVER THE OPEN WATERS. ACTIVE PATTERN WITH SEVERAL FAST MOVING SYSTEMS TO CONTINUE FOR A WHILE. ANOTHER COLD FRONT MOVING THROUGH EARLY MONDAY WILL RESULT IN GUST NORTHWEST TO NORTH WINDS AND LIKELY SMALL CRAFT ADVISORY CONDITIONS MONDAY INTO TUESDAY. AS A POLAR HIGH PRESSURE AREA MOVES SOUTH OF THE GREAT LAKES WEDNESDAY...A STRONG SOUTHWEST FLOW REGIME WILL DEVELOP AND CONTINUE INTO THURSDAY. GALE FORCE WINDS ARE POSSIBLE OVER THE OPEN WATERS AND AT LEAST SMALL CRAFT ADVISORY CONDITIONS IN THE NEAR SHORE WATERS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR LMZ643>646. && $$ UPDATE...ET/WOOD TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN SUNDAY THROUGH FRIDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 AM CST SAT NOV 9 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 332 AM CST SAT NOV 9 2013 A MAINLY CLOUDY AND SEASONALLY COOL DAY IS ON TAP FOR THE REGION AS A LOW PRESSURE SYSTEM DRIFTS THROUGH THE NORTHERN GREAT LAKES. MOST OF THE PRECIPITATION WITH THIS SYSTEM HAS SHIFTED TO THE NORTHEAST AHEAD OF THE LEAD MID LEVEL SHORT WAVE TROUGH THAT IS NOW INTO THE UP OF MICHIGAN. A SECONDARY MID LEVEL SHORT WAVE TROUGH IS CURRENTLY IN THE EASTERN DAKOTAS AND WILL PROPAGATE TO THE EAST TODAY THROUGH THE BROAD CYCLONIC FLOW ALOFT. THIS FEATURE WILL PULL SOME COOLER AIR DOWN WITH IT AND CREATE SOME STEEP LOW LEVEL LAPSE RATES TODAY. THIS SHOULD LEAD TO A FAIRLY WIDESPREAD STRATUS/STRATOCUMULUS LAYER FORMING AND HOLDING ON THROUGH MUCH OF THE DAY. LOW LEVEL LIFT LOOKS FAIRLY WEAK AND SHOULD NOT BE ENOUGH TO DEVELOP ANY SPRINKLES OR FLURRIES. DUE TO THE CLOUD COVER THAT IS EXPECTED TO BE AROUND FOR MUCH OF THE DAY...HAVE KNOCKED HIGH TEMPERATURES BACK A FEW DEGREES. A SURFACE RIDGE OF HIGH PRESSURE WILL THEN MOVE INTO THE UPPER MISSISSIPPI RIVER VALLEY TONIGHT AND WILL HELP TO CLEAR SKIES ACROSS MUCH OF THE REGION. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 332 AM CST SAT NOV 9 2013 THE MAIN FOCUS FOR NEXT WEEK IS ON THE COLD AIR THAT IS PRIMED TO TAKE OVER THE REGION THROUGH MID WEEK. THE TREND CONTINUES TO BE GOING TOWARD A FASTER SOLUTION WITH THE FRONTAL PASSAGE COMING THROUGH SUNDAY NIGHT INTO EARLY MONDAY MORNING. 850MB TEMPERATURES DROP FROM AROUND 0C ON SUNDAY TO AROUND -15C BY MONDAY NIGHT. THIS WILL LEAD TO TEMPERATURES STRUGGLING TO GET TO 30F ON TUESDAY AS A RIDGE OF HIGH PRESSURE MOVES INTO THE REGION. 09.00Z NAM/GFS STANDARDIZED 850MB TEMPERATURE ANOMALIES SHOWS ABOUT -2 DEVIATIONS FROM NORM MONDAY NIGHT INTO TUESDAY MORNING...WHICH TYPICALLY MEANS THAT LOW TEMPERATURES COULD BE APPROACHING RECORD LEVELS. THE RECORD LOWS ARE PRETTY LOW FOR THESE TWO DAYS...SO AM NOT EXPECTING THEM TO BE BROKEN BUT THIS WILL DEFINITELY BE THE COLDEST AIR MASS OF THE SEASON SO FAR. THE OTHER PART OF THIS SYSTEM IS WITH WHETHER THERE WILL BE ANY PRECIPITATION TO FORM BEHIND/ALONG THE COLD FRONT/MID LEVEL TROUGH. THE STRONGER MID LEVEL FORCING IS OFF TO THE EAST WHERE THE MAIN TROUGH IS GOING TO TRACK...BUT THERE COULD BE ENOUGH LIFT FROM THE TROUGH AND LOW LEVEL FRONTOGENESIS TO BE ABLE TO PRODUCE SOME PRECIPITATION. IT LOOKS LIKE MOST OF THE PRECIPITATION WOULD OCCUR IN THE COLD AIR MASS BEHIND THE FRONT...WHICH WOULD MAINLY BE IN THE FORM OF SNOW. WITH IT LOOKING LIKE A PRETTY QUICK SHOT...AM NOT EXPECTING MUCH IF ANY ACCUMULATIONS FROM IT. THE BETTER CHANCE FOR IT IS FURTHER EAST IN WISCONSIN WHERE THE FORCING IS A BIT DEEPER. GOING TOWARD THE END OF THE WEEK...THE COLD AIR STARTS TO GET PUSHED TO THE EAST ON THURSDAY ALREADY WITH MID LEVEL RIDGING QUICKLY COMING IN BEHIND THE TROUGH. SO TEMPERATURES SHOULD REBOUND BACK CLOSER TO SEASONAL NORMS WITH SOME LOW CHANCES FOR SOME PRECIPITATION THURSDAY NIGHT INTO FRIDAY AS A WEAK MID LEVEL TROUGH AND SURFACE COLD FRONT MOVE INTO THE REGION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1100 AM CST SAT NOV 9 2013 PROBLEMATIC CIG FORECAST. LATEST SATELLITE AND SFC OBS POINT TO A BROAD EXPANSE OF MOSTLY MVFR CIGS EXTENDING FROM THE UPPER MISSISSIPPI RIVER VALLEY ACROSS ND...ASSOCIATED WITH A LOW TRACKING EAST ACROSS THE NORTHERN GREAT LAKES. NAM/GFS SUGGEST THAT SUBSIDENCE AND MIXING DOWN OF DRIER MID LEVEL AIR WILL ERODE THE SOUTHERN FLANK OF THE LOW STRATUS...RESULTING IN CLEARING SKIES AT KRST/KLSE BY MID TO LATE AFTERNOON. THE RAP IS QUITE DIFFERENT...HOLDING ONTO THIS LOW SATURATION THROUGH MUCH OF THE EVENING. ALL THE MODELS HOLD ONTO A 850-800 MB INVERSION THROUGH SUNDAY AFTERNOON...SO IF THE MOISTURE REMAINS TRAPPED...CLOUDS AND THE MVFR CIGS COULD HANG AROUND TODAY/TONIGHT. MODELS ARE ALL DOING A DECENT JOB DEPICTING WHERE THE CLOUDS ARE CURRENTLY. GOING TO STEER THE TAFS TOWARD THE PESSIMISTIC SIDE. MODELS HAVE A TENDENCY TO CLEAR CLOUDS A BIT TOO FAST IN FALL/WINTER...AND THIS MIGHT BE THE CASE HERE. IF MIXING BECOMES EVIDENT...WITH CLOUDS ERODING...TAFS WILL NEED TO BE UPDATED FOR THE QUICKER CLEARING TREND. AS FOR WINDS...TIGHT PRESSURE GRADIENT WILL KEEP THEM RELATIVELY STRONG/GUSTY INTO THE EARLY EVENING HOURS. HIGH PRESSURE IS SLATED TO BUILD IN FROM THE NORTHERN PLAINS SUNDAY MORNING...SO LOOK FOR DECREASING WINDS OVERNIGHT...WITH A SHIFT TO SOUTHWEST SUNDAY AFTERNOON. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM....HALBACH AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1050 PM CST FRI NOV 8 2013 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .UPDATE... ISSUED AT 655 PM CST FRI NOV 8 2013 SO FAR...ONLY SCT MIXED PCPN HAS BEEN REPORTED OVER NC WI...AS WAS EXPECTED BY THE PREVIOUS SHIFT. OVERALL...NOT MUCH ORGANIZATION SEEN ON THE AREA RADAR MOSAIC...BUT THIS IS EXPECTED TO CHANGE OVER THE NEXT FEW HOURS. 22Z HRRR SHOWS SCT PCPN OVER SE MN/W WI BLOSSOMING AS IT PIVOTS NORTHEAST OVER THE NEXT FEW HOURS...DUE TO STRONG LIFT ASSOCIATED WITH THE APPROACHING S/W TROF...WAA AND THE LFQ OF THE UPPER JET. CURRENT THINKING IS THAT POPS MAY NEED TO BE INCREASED OVER MOST OF THE FORECAST AREA DURING THE LATE EVENING AND OVERNIGHT HOURS. ALSO CONCERNED THAT PCPN-TYPE MAY END UP BEING MAINLY SNOW OVER FAR NORTHERN WI...WHERE LOW-LEVEL WET BULB TEMPS ARE HOVERING AT OR A LITTLE BLO FREEZING. CROSSHAIRS SIGNATURES (MAX OMEGA COINCIDENT WITH DENDRITIC GROWTH ZONE) SHOWING UP ON TIMESECTIONS OVER THE FAR NORTH...SO A FEW HOURS OF MODERATE SNOW IS POSSIBLE. MAY NEED TO BUMP UP ACCUMS A LITTLE BIT THERE...BUT PROBABLY NOT ENOUGH TO WARRANT AN ADVISORY...ESPECIALLY SINCE ITS OCCURRING DURING THE OVERNIGHT HOURS. && .SHORT TERM...TONIGHT AND SATURDAY ISSUED AT 310 PM CST FRI NOV 8 2013 SEVERAL ISSUES TO DEAL WITH AS A QUICK MOVING SYSTEM TRACKS ACROSS THE GREAT LAKES. FIRST ISSUE WILL BE DEALING WITH A BAND OF WARM AIR ADVECTION (WAA) PRECIP PUSHING INTO WESTERN WISCONSIN. THIS AREA SHOULD CONTINUE TO PUSH EAST/NORTHEAST ACROSS MUCH OF NORTHERN WI LATE THIS AFTERNOON AND EVENING. SURFACE TEMPS SUPPORTIVE OF RAIN...HOWEVER EVAPORATIVE COOLER SHOULD COOL THE COLUMN ENOUGH TO HAVE SOME MIXED PRECIP ACROSS THE NORTH. HAD REPORTS OF SPRINKLES...FLURRIES...AND EVEN SLEET WITH THE PRECIP TO OUR WEST. SO WITHOUT MAKING IT TOO COMPLICATED IN THE GRIDS...WILL CARRY A CHANCE OF RAIN/SNOW/SLEET FOR MUCH OF CENTRAL AND NORTHERN WI...WITH RAIN OVER FOX VALLEY AND LAKESHORE. ONCE THE WAA PRECIP PUSHES EAST OF THE AREA...FORCING ASSOCIATED WITH THE SURFACE LOW AND UPPER TROF WILL SPREAD MORE PRECIP ACROSS THE AREA. BEST AREA OF FORCING WILL BE ACROSS FAR NORTHERN WI AND UPPER MICHIGAN...WHERE SHORTWAVE ENERGY WILL COMBINE WITH THE SURFACE LOW THE LEFT FRONT QUAD OF AN UPPER JET. WILL CARRY LIKELY POPS NORTH AND HIGH-END CHANCE POPS SOUTH. OTHER THAN SOME BRIEF MIXING WITH SLEET (OR SNOW) SOUTH OF A WAUSAU TO MARINETTE LINE... MAINLY RAIN IS EXPECTED. ACROSS THE NORTH...PRECIP TYPE WILL BE MORE OF A CONCERN. CRITICAL RAIN/SNOW THICKNESSES HOVER AROUND THE MI/WI BORDER MUCH OF THE NIGHT...SO EXPECT A MIX OF RAIN AND SNOW NORTH OF RHI...WITH MORE SNOW CLOSER TO THE BORDER. MODELS SHOW UP TO 0.3 INCHES OF QPF THROUGH SATURDAY MORNING...SO IF IT IS ALL SNOW COULD GET UP TO 3 INCHES...HOWEVER EXPECT SOME MIXING TO OCCUR SO WILL HOLD ACCUMULATIONS UNDER 2 INCHES. SOUTH WINDS WILL BECOME GUSTY AS THE PRESSURE GRADIENT TIGHTENS UP LATE TONIGHT. CYCLONIC ALOFT KICKS IN BEHIND THE SYSTEM ON SATURDAY. PRECIP SHOULD SHUT OFF FOR MOST LOCATIONS...EXCEPT OVER THE NORTH WHERE CYCLONIC FLOW AND LINGER MOISTURE COULD LEAD TO SOME LIGHT RAIN OR SNOW. THE CYCLONIC FLOW WILL KEEP CLOUDS ACROSS THE AREA FOR MUCH OF THE DAY...BUT DRIER AIR SHOULD ALLOW FOR DECREASING CLOUDS IN THE AFTERNOON OVER CENTRAL AND EAST CENTRAL WI. SATURDAY WILL BE BLUSTERY AS 925MB WINDS OF 30-40 WILL RESIDE ACROSS THE AREA THROUGH THE DAY. MIXING TO AROUND 3000FT SHOULD ALLOW GUSTS TO REACH BETWEEN 25-35 MPH ACROSS CENTRAL AND EAST-CENTRAL WI. COLD AIR ADVECTION NOT VERY STRONG DURING THE DAY...AND WITH WEST/DOWNSLOPING WINDS...TEMPS SHOULD ACTUALLY BE SLIGHTLY WARMER THAN TODAY. .LONG TERM...SATURDAY NIGHT THROUGH FRIDAY ISSUED AT 310 PM CST FRI NOV 8 2013 MAIN STORY FOR THIS PERIOD WILL BE THE BELOW NORMAL TEMPERATURES THROUGHOUT THE PERIOD...WITH SOME OF THE COLDEST AIR OF THE SEASON EXPECTED MONDAY INTO TUESDAY. FOR SATURDAY NIGHT...850MB WINDS ARE EXPECTED TO TURN TO THE NORTHWEST...BRINGING A GOOD CHANCE OF LAKE EFFECT SNOW SHOWERS OR FLURRIES TO THE FAR NORTH. THE 850MB WINDS ARE EXPECTED TO BACK SUNDAY MORNING...BRINGING AN END TO THE LAKE EFFECT SNOW SHOWERS OR FLURRIES. THE NEXT SYSTEM WILL BE DROPPING SOUTH ACROSS THE AREA SUNDAY NIGHT...BRINGING ANOTHER CHANCE OF LIGHT SNOW TO MUCH OF THE AREA. LIKE SATURDAY NIGHT...WINDS WILL TURN MORE FAVORABLE FOR LAKE EFFECT SNOW SHOWERS ACROSS FAR NORTHERN WISCONSIN THAT WILL LINGER INTO MONDAY. SOME QUESTIONS LINGER ABOUT THE AMOUNT OF DRY AIR THAT WILL FILTER INTO THE REGION FROM LARGE SPRAWLING CANADIAN HIGH. THINK LAKE EFFECT SNOW SHOWERS WILL DIMINISH OR END MONDAY BASED ON THE LATEST MODEL RUNS FROM THIS MORNING. ATTENTION THEN TURNS TO SOME OF THE COLDEST AIR OF THE SEASON MONDAY INTO TUESDAY. VERY COLD AIR AT 850MB (-16C TO -19C) EXPECTED TO PLUNGE ACROSS THE AREA DURING THE DAY MONDAY. EXPECT STEADY OR FALLING TEMPERATURES THROUGHOUT THE DAY. HAVE DEPICTED FALLING TEMPERATURES IN THE GRIDS. THE COMBINATION OF THE COLD TEMPERATURES AND GUSTY NORTHWEST WINDS WILL CREATE WIND CHILL READINGS IN THE SINGLE DIGITS ABOVE ZERO AND TEENS MONDAY AFTERNOON. HIGH TEMPERATURES ON TUESDAY WILL BE BELOW FREEZING ACROSS MUCH OF THE AREA. COLD CANADIAN HIGH WILL DOMINATE THE WEATHER PATTERN TUESDAY THROUGH THURSDAY. POTENTIAL WEAK SYSTEM COULD BRING A CHANCE OF LIGHT SNOW THURSDAY NIGHT...BUT DECIDED TO LEAVE THIS PERIOD DRY FOR NOW DUE TO MOISTURE CONCERNS. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1043 PM CST FRI NOV 8 2013 STEADY PCPN WILL TAPER OFF FROM SW TO NE BETWEEN 08Z-10Z/SAT. UNTIL THEN...EXPECT MAINLY RAIN SOUTH OF A LINE FROM AUW TO MNM...A MIX OF RAIN...SNOW AND POSSIBLY SOME SLEET A BIT FARTHER NORTH...AND MAINLY SNOW OVER THE FAR NORTH. MVFR CONDITIONS ARE POSSIBLE OVER MOST OF THE FORECAST AREA...WITH SOME IFR/LIFR CONDITIONS EXPECTED WITH THE HEAVIER SNOW OVER NORTHERN WI. MVFR CIGS WILL LIKELY PERSIST INTO SATURDAY. LLWS SHOULD TAPER OFF LATE TONIGHT...BUT GUSTY WEST SURFACE WINDS WILL OCCUR DURING THE DAY ON SATURDAY. && .MARINE... ISSUED AT 310 PM CST FRI NOV 8 2013 SOUTH WINDS WILL RAMP UP THIS EVENING AHEAD OF A LOW PRESSURE SYSTEM. MODELS CONTINUE TO SHOW 925MB WINDS BETWEEN 40-50 KTS BETWEEN 03-12Z SATURDAY. ONLY CONCERN IS DEGREE OF MIXING WITH WARM AIR ADVECTION. WITH IMPRESSIVE WINDS ALOFT...ONLY MINIMAL MIXING SHOULD BRING DOWN GALE FORCE GUSTS...SO WILL UPGRADE THE NEARSHORE WATERS OF LAKE MICHIGAN TO A GALE WARNING FROM 00-12Z SATURDAY. SOME GALE FORCE GUSTS ARE POSSIBLE AFTER 12Z...BUT WINDS ALOFT DIMINISH SLIGHTLY SO THEY SHOULD NOT BE AS FREQUENT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........KIECKBUSCH SHORT TERM.....BERSCH LONG TERM......ECKBERG AVIATION.......KIECKBUSCH MARINE.........BERSCH
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
327 AM EST MON NOV 11 2013 .SYNOPSIS... DRY HIGH PRESSURE WILL DOMINATE THROUGH MONDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE TUESDAY OR EARLY WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... EARLY THIS MORNING...A DRY COLD FRONT IS IN THE PROCESS OF MOVING THROUGH THE SOUTHERN PART OF THE FA AND THE CSRA EARLY THIS MORNING. THE FRONT WILL CONTINUE MOVING SOUTHWARD POSSIBLY MOVING SOUTH OF THE AREA BY DAYBREAK, INCREASED MIXING ASSOCIATED WITH RELATIVELY WARM WATER TEMPERATURES WILL RESULT IN BREEZY CONDITIONS BEHIND THE FRONT ON AREA LAKES. THE HRRR SHOWS LAKE WINDS CURRENTLY ABOUT 15 KNOTS WELL BELOW THE LAKE WIND ADVISORY CRITERIA. VWP SHOWS 1 KFT WINDS 35 KT AND THE RUC13 FORECAST SOUNDING ALSO SHOWS 1500 FOOT WINDS NE 33 KT AT 09Z WHILE NAM BUFR SOUNDING GIVE 1500 FOOT WINDS NE AT 28 KT. SO IF WINDS MIX DOWN ON LAKE MARION...THERE COULD BE SOME WIND GUSTS IN THE 20-25 KT RANGE. SOUNDINGS INDICATE A LOW LEVEL INVERSION BUT HRRR TEMPERATURES OVER LAKE MARION ARE 50-55 DEGREES. SO THE WINDS MAY MIX DOWN. SURFACE TEMPERATURES ARE IN THE 40S. WILL CONTINUE TO MONITOR FOR THE NEXT FEW HOURS. MONDAY...HIGH PRESSURE WILL CONTINUE TO BUILD SOUTHWARD INTO THE REGION WITH DRIER AIR AND TEMPERATURES COOLER THAN YESTERDAY. A DECREASING PRESSURE GRADIENT SHOULD ALLOW WINDS TO DROP OFF LATER THIS MORNING. RIGHT NOW WILL CONTINUE LAKE WIND ADVISORY FOR LAKE MARION UNTIL 11 AM BUT WINDS MAY DROP OFF 2-3 HOURS EARLY. WILL CONTINUE TO MONITOR. HIGH TEMPERATURES LOWER 60S NORTH TO UPPER 60S SOUTH STILL LOOK OK. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... MODELS IN GOOD AGREEMENT WITH PATTERN CHANGE TUESDAY AS HIGHLY AMPLIFIED POSITIVELY TILTED UPPER-LEVEL TROUGH DEVELOPS IN THE EASTERN STATES...RIDGE OUT WEST. THIS TROUGH WILL TRANSPORT VERY COLD AIR FOR THIS TIME OF YEAR INTO THE SOUTHEAST...ARCTIC AIR MASS ORIGIN. LATEST MODELS RUN SUGGEST MORE CLOUDINESS BY EARLY AFTERNOON AS FRONT APPROACHES SO CUT TEMPERATURES FROM PREVIOUS FORECAST AND INCREASED WINDS BEHIND THE FRONT AS STRONG COLD ADVECTION DEVELOPS. THE FRONT SHOULD PUSH THROUGH THE AREA BY LATE TUESDAY. THE COLDEST AIR OF THE SEASON WILL SPREAD ACROSS THE REGION TUESDAY NIGHT. PRECIPITATION MAY MOVE THROUGH THE AREA...ALTHOUGH QPF EXPECTED TO BE QUITE LOW. MODELS APPEAR TO BE COMING MORE INTO ALIGNMENT WITH THE UPCOMING WEATHER EVENT. MODELS ARE TRENDING LESS AGGRESSIVE IN BRINGING IN ANY SORT OF BRIEF WINTRY MIX THAN PREVIOUS RUNS. IN FACT...LATEST GFS AND NAM KEEP PRECIPITATION ALL LIQUID FOR LATE TUESDAY NIGHT. NAM AND GFS BUFKIT INDICATING RELATIVELY SHALLOW MOISTURE WELL BELOW THE SNOW GROWTH ZONE. BEST SYNOPTIC LIFT WILL BE MAINLY OVER THE NC MOUNTAINS. POPS AND QPFS REMAIN LOW. OVERNIGHT LOWS SHOULD DIP INTO THE LOWER TO MIDDLE 30S EARLY WEDNESDAY MORNING...BUT THE BULK OF THE MOISTURE WILL HAVE MOVED EAST OF THE AREA BY THE TIME THE COLDEST TEMPERATURES ARRIVE AROUND SUNRISE WEDNESDAY. HIGHS WEDNESDAY WILL RANGE FROM THE MID 40S NORTH TO THE LOWER 50S SOUTH. WITH A DEVELOPING TIGHT PRESSURE GRADIENT...IT WILL BECOME RATHER BREEZY TUESDAY NIGHT INTO WEDNESDAY WITH SUSTAINED WIND SPEEDS OF 15 TO 25 MPH FROM THE NORTH AND NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WINDS WILL SUBSIDE BY LATE WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. HIGH PRESSURE EXPECTED TO CONTINUE INTO FRIDAY. THE GFS AND ECMWF SHOW A DEVELOPING WARM FRONT WITH WEAK ISENTROPIC LIFT SUPPORTING LOW CHANCE POPS SATURDAY AND SUNDAY. TEMPERATURES BELOW NORMAL THROUGH FRIDAY...MUCH BELOW WEDNESDAY AND THURSDAY. TEMPERATURES WILL MODERATE SATURDAY AND SUNDAY AHEAD OF THE NEXT FRONTAL SYSTEM. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE 24 HOUR TAF PERIOD. A DRY FRONT WILL CONTINUE TO PUSH SOUTH THROUGH THE REGION OVERNIGHT/EARLY THIS MORNING. INFLUX OF DRIER AIR ALONG WITH SOME WIND IS EXPECTED TO PRECLUDE FOG FORMATION. HIGH PRESSURE CENTER WILL BUILD IN THIS AFTERNOON...LEADING TO DECREASING WIND SPEEDS. EXTENDED AVIATION OUTLOOK...A COLD FRONT AND UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO EARLY WEDNESDAY...PROVIDING A SLIGHT CHANCE OF LIGHT PRECIPITATION...AND ASSOCIATED RESTRICTIONS. BREEZY CONDITIONS WILL BE POSSIBLE AS WELL TUE NT/WED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...LAKE WIND ADVISORY UNTIL 11 AM EST THIS MORNING FOR SCZ031- 036>038. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
146 AM EST MON NOV 11 2013 .SYNOPSIS... DRY HIGH PRESSURE WILL DOMINATE THROUGH MONDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE TUESDAY OR EARLY WEDNESDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A DRY COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TONIGHT. INCREASED MIXING ASSOCIATED WITH RELATIVELY WARM WATER TEMPERATURES WILL RESULT IN BREEZY CONDITIONS BEHIND THE FRONT ON AREA LAKES. THE HRRR SHOWS LAKE WINDS CURRENTLY ABOUT 15 KNOTS WELL BELOW THE LAKE WIND ADVISORY CRITERIA. VWP SHOWS 1 KFT WINDS 30 KT AND THE RUC13 FORECAST SOUNDING ALSO SHOWS 1500 FOOT WINDS NE 33 KT AT 09Z WHILE NAM BUFR SOUNDING GIVE 1500 FOOT WINDS NE AT 28 KT. SO IF WINDS MIX DOWN ON LAKE MARION...THERE COULD BE SOME WIND GUSTS IN THE 20-25 KT RANGE. SOUNDINGS INDICATE A LOW LEVEL INVERSION BUT HRRR TEMPERATURES OVER LAKE MARION ARE 50-55 DEGREES. SO THE WINDS MAY MIX DOWN. SURFACE TEMPERATURES ARE IN THE 40S. WILL CONTINUE TO MONITOR FOR THE NEXT FEW HOURS. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/... DRY HIGH PRESSURE DOMINATES THROUGH MONDAY. MODELS IN GOOD AGREEMENT WITH PATTERN CHANGE TUESDAY AS HIGHLY AMPLIFIED POSITIVELY TILTED UPPER-LEVEL TROUGH DEVELOPS IN THE EASTERN STATES...RIDGE OUT WEST. THIS TROUGH WILL TRANSPORT VERY COLD AIR FOR THIS TIME OF YEAR INTO THE SOUTHEAST...ARCTIC AIR MASS ORIGIN. LATEST MODELS RUN SUGGEST MORE CLOUDINESS BY EARLY AFTERNOON AS FRONT APPROACHES SO CUT TEMPERATURES FROM PREVIOUS FORECAST AND INCREASED WINDS BEHIND THE FRONT AS STRONG COLD ADVECTION DEVELOPS. THE FRONT SHOULD PUSH THROUGH THE AREA BY LATE TUESDAY. THE COLDEST AIR OF THE SEASON WILL SPREAD ACROSS THE REGION TUESDAY NIGHT. PRECIPITATION MAY MOVE THROUGH THE AREA...ALTHOUGH QPF EXPECTED TO BE QUITE LOW. MODELS APPEAR TO BE COMING MORE INTO ALIGNMENT WITH THE UPCOMING WEATHER EVENT. MODELS ARE TRENDING LESS AGGRESSIVE IN BRINGING IN ANY SORT OF BRIEF WINTRY MIX THAN PREVIOUS RUNS. IN FACT...LATEST GFS AND NAM KEEP PRECIPITATION ALL LIQUID FOR LATE TUESDAY NIGHT. NAM AND GFS BUFKIT INDICATING RELATIVELY SHALLOW MOISTURE WELL BELOW THE SNOW GROWTH ZONE. BEST SYNOPTIC LIFT WILL BE MAINLY OVER THE NC MOUNTAINS. POPS AND QPFS REMAIN LOW. OVERNIGHT LOWS SHOULD DIP INTO THE LOWER TO MIDDLE 30S EARLY WEDNESDAY MORNING...BUT THE BULK OF THE MOISTURE WILL HAVE MOVED EAST OF THE AREA BY THE TIME THE COLDEST TEMPERATURES ARRIVE AROUND SUNRISE WEDNESDAY. HIGHS WEDNESDAY WILL RANGE FROM THE MID 40S NORTH TO THE LOWER 50S SOUTH. WITH A DEVELOPING TIGHT PRESSURE GRADIENT...IT WILL BECOME RATHER BREEZY TUESDAY NIGHT INTO WEDNESDAY WITH SUSTAINED WIND SPEEDS OF 15 TO 25 MPH FROM THE NORTH AND NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WINDS WILL SUBSIDE BY LATE WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. HIGH PRESSURE EXPECTED TO CONTINUE INTO FRIDAY. THE GFS AND ECMWF SHOW A DEVELOPING WARM FRONT WITH WEAK ISENTROPIC LIFT SUPPORTING LOW CHANCE POPS SATURDAY AND SUNDAY. TEMPERATURES BELOW NORMAL THROUGH FRIDAY...MUCH BELOW WEDNESDAY AND THURSDAY. TEMPERATURES WILL MODERATE SATURDAY AND SUNDAY AHEAD OF THE NEXT FRONTAL SYSTEM. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE 24 HOUR TAF PERIOD. A DRY FRONT WILL CONTINUE TO PUSH SOUTH THROUGH THE REGION OVERNIGHT/EARLY THIS MORNING. INFLUX OF DRIER AIR ALONG WITH SOME WIND IS EXPECTED TO PRECLUDE FOG FORMATION. HIGH PRESSURE CENTER WILL BUILD IN THIS AFTERNOON...LEADING TO DECREASING WIND SPEEDS. EXTENDED AVIATION OUTLOOK...A COLD FRONT AND UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO EARLY WEDNESDAY...PROVIDING A SLIGHT CHANCE OF LIGHT PRECIPITATION...AND ASSOCIATED RESTRICTIONS. BREEZY CONDITIONS WILL BE POSSIBLE AS WELL TUE NT/WED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...LAKE WIND ADVISORY UNTIL 11 AM EST THIS MORNING FOR SCZ031- 036>038. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1237 AM EST MON NOV 11 2013 .SYNOPSIS... DRY HIGH PRESSURE WILL DOMINATE THROUGH MONDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE TUESDAY OR EARLY WEDNESDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A DRY COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TONIGHT. INCREASED MIXING ASSOCIATED WITH RELATIVELY WARM WATER TEMPERATURES WILL RESULT IN BREEZY CONDITIONS BEHIND THE FRONT ON AREA LAKES. THE HRRR INDICATES LAKE WIND ADVISORY CRITERIA ON LAKE MARION. THE PRESSURE GRADIENT APPEARS A LITTLE LESS FARTHER WEST. SATELLITE TRENDS SUPPORT MOSTLY CLEAR SKIES. MIXING SHOULD HELP HOLD UP TEMPERATURES. WE LEANED TOWARD THE WARMER TEMPERATURE GUIDANCE. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/... DRY HIGH PRESSURE DOMINATES THROUGH MONDAY. MODELS IN GOOD AGREEMENT WITH PATTERN CHANGE TUESDAY AS HIGHLY AMPLIFIED POSITIVELY TILTED UPPER-LEVEL TROUGH DEVELOPS IN THE EASTERN STATES...RIDGE OUT WEST. THIS TROUGH WILL TRANSPORT VERY COLD AIR FOR THIS TIME OF YEAR INTO THE SOUTHEAST...ARCTIC AIR MASS ORIGIN. LATEST MODELS RUN SUGGEST MORE CLOUDINESS BY EARLY AFTERNOON AS FRONT APPROACHES SO CUT TEMPERATURES FROM PREVIOUS FORECAST AND INCREASED WINDS BEHIND THE FRONT AS STRONG COLD ADVECTION DEVELOPS. THE FRONT SHOULD PUSH THROUGH THE AREA BY LATE TUESDAY. THE COLDEST AIR OF THE SEASON WILL SPREAD ACROSS THE REGION TUESDAY NIGHT. PRECIPITATION MAY MOVE THROUGH THE AREA...ALTHOUGH QPF EXPECTED TO BE QUITE LOW. MODELS APPEAR TO BE COMING MORE INTO ALIGNMENT WITH THE UPCOMING WEATHER EVENT. MODELS ARE TRENDING LESS AGGRESSIVE IN BRINGING IN ANY SORT OF BRIEF WINTRY MIX THAN PREVIOUS RUNS. IN FACT...LATEST GFS AND NAM KEEP PRECIPITATION ALL LIQUID FOR LATE TUESDAY NIGHT. NAM AND GFS BUFKIT INDICATING RELATIVELY SHALLOW MOISTURE WELL BELOW THE SNOW GROWTH ZONE. BEST SYNOPTIC LIFT WILL BE MAINLY OVER THE NC MOUNTAINS. POPS AND QPFS REMAIN LOW. OVERNIGHT LOWS SHOULD DIP INTO THE LOWER TO MIDDLE 30S EARLY WEDNESDAY MORNING...BUT THE BULK OF THE MOISTURE WILL HAVE MOVED EAST OF THE AREA BY THE TIME THE COLDEST TEMPERATURES ARRIVE AROUND SUNRISE WEDNESDAY. HIGHS WEDNESDAY WILL RANGE FROM THE MID 40S NORTH TO THE LOWER 50S SOUTH. WITH A DEVELOPING TIGHT PRESSURE GRADIENT...IT WILL BECOME RATHER BREEZY TUESDAY NIGHT INTO WEDNESDAY WITH SUSTAINED WIND SPEEDS OF 15 TO 25 MPH FROM THE NORTH AND NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WINDS WILL SUBSIDE BY LATE WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. HIGH PRESSURE EXPECTED TO CONTINUE INTO FRIDAY. THE GFS AND ECMWF SHOW A DEVELOPING WARM FRONT WITH WEAK ISENTROPIC LIFT SUPPORTING LOW CHANCE POPS SATURDAY AND SUNDAY. TEMPERATURES BELOW NORMAL THROUGH FRIDAY...MUCH BELOW WEDNESDAY AND THURSDAY. TEMPERATURES WILL MODERATE SATURDAY AND SUNDAY AHEAD OF THE NEXT FRONTAL SYSTEM. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE 24 HOUR TAF PERIOD. A DRY FRONT WILL CONTINUE TO PUSH SOUTH THROUGH THE REGION OVERNIGHT/EARLY THIS MORNING. INFLUX OF DRIER AIR ALONG WITH SOME WIND IS EXPECTED TO PRECLUDE FOG FORMATION. HIGH PRESSURE CENTER WILL BUILD IN THIS AFTERNOON...LEADING TO DECREASING WIND SPEEDS. EXTENDED AVIATION OUTLOOK...A COLD FRONT AND UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO EARLY WEDNESDAY...PROVIDING A SLIGHT CHANCE OF LIGHT PRECIPITATION...AND ASSOCIATED RESTRICTIONS. BREEZY CONDITIONS WILL BE POSSIBLE AS WELL TUE NT/WED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...LAKE WIND ADVISORY UNTIL 11 AM EST THIS MORNING FOR SCZ031- 036>038. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
352 AM CST MON NOV 11 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM CST MON NOV 11 2013 MAIN FORECAST CONCERNS WILL BE TEMPERATURES AND FOG EARLY THIS MORNING. SURFACE ANALYSIS SHOWS A COLD FRONT ACROSS CENTRAL NEBRASKA AT THIS TIME THAT HAS BEEN STEADILY MOVING TO THE SOUTH ACROSS NORTHERN NEBRASKA EARLY THIS MORNING. SATELLITE SHOWS SOME CLOUDS A WAYS BEHIND THE COLD FRONT. SURFACE OBSERVATIONS HAVE SOME SPOTTY FOG THAT HAS BEEN REDUCING VISIBILITIES TO LESS THAN A MILE AT TIMES. DEW POINTS ACROSS THE AREA ARE FAIRLY HIGH...IN THE UPPER 30S TO MID 40S. AS TEMPERATURES FALL OFF THE VISIBILITY DROPS IN FOG. EXPECT THAT WITH THE LIGHT WINDS AHEAD OF THE FRONT AND THE MOIST AIR THERE WILL BE SOME FOG ACROSS THE AREA EARLY THIS MORNING. AS THE COLD FRONT MOVES SOUTH THE WINDS WILL TURN TO THE NORTH AND START TO INCREASE. THIS SHOULD BRING AN END TO THE FOG THIS MORNING. THE MAIN QUESTION WILL BE HOW WIDESPREAD THE FOG WILL BE AND HOW LOW THE VISIBILITIES WILL DROP. THE HRRR AND SREF BOTH REDUCE VISIBILITIES TO LESS THAN A MILE. WILL START WITH THAT AND WATCH. THE COLD FRONT IS EXPECTED TO BE MOST...IF NOT ALL...OF THE WAY THROUGH THE FORECAST AREA BY SUNRISE THIS MORNING. BEHIND THIS COLD FRONT THERE IS VERY COLD AIR THAT WILL BE PUSHING INTO THE FORECAST AREA. TEMPERATURES ARE NOT LIKELY TO WARM VERY MUCH AT ALL TODAY AND WILL PROBABLY FALL THROUGHOUT THE DAY. CLOUDS WILL PUSH INTO THE FORECAST AREA DURING THE DAY. THERE IS A FAIRLY TIGHT PRESSURE GRADIENT BEHIND THE COLD FRONT AS WELL. WINDS ALOFT REMAIN MAINLY 10 TO 20 KNOTS SO THE WIND SHOULD BE BREEZY WITH 10 TO 20 MPH AND GUSTS TO AROUND 25 MPH OR SO. A COLD HIGH PRESSURE SYSTEM WILL BUILD INTO THE FORECAST AREA TONIGHT. WITH THIS THE WINDS WILL BE LIGHT...SKIES WILL CLEAR OUT AND TEMPERATURES WILL CONTINUE TO DROP THROUGH THE NIGHT. LOW TEMPERATURES IN THE MORNING WILL BE IN THE 5 TO 15 DEGREE RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 353 AM CST MON NOV 11 2013 A STRONG SURFACE HIGH PRESSURE SYSTEM WILL BE NEARLY CENTERED OVER THE FORECAST AREA TO START THE EXTENDED PERIODS...AND IS EXPECTED TO DRIFT SLOWLY SOUTHWEST DURING THE DAY TUESDAY. THEREFORE...WHILE WINDS WILL BE GENERALLY LIGHT AND SHIFTING OUT OF THE OF THE SOUTH DURING THE AFTERNOON HOURS...TEMPERATURES WILL BE ON THE COLD SIDE...AS THE HEART OF THE APPROACHING COLD AIRMASS WILL ENCOMPASS THE ENTIRE FORECAST AREA. AS A RESULT...EXPECTED HIGH TEMPERATURES TUESDAY TO STRUGGLE TO REACH THE MIDDLE 30S ACROSS THE ENTIRE AREA...OR ALMOST 20 DEGREES BELOW NORMAL. TEMPERATURES WILL CONTINUE TO BE THE FOCUS TUESDAY NIGHT...ALBEIT THE AIRMASS WILL HAVE MODIFIED SOME SINCE MONDAY NIGHT THANKS TO SOUTHWESTERLY RETURN FLOW...AND EXPECT TEMPERATURES TO BOTTOM OUT IN THE UPPER TEENS TO LOWER 20S...OR ABOUT 10 DEGREES BELOW NORMAL MID NOVEMBER LOWS. THEREAFTER...THE UPPER LEVEL PATTERN WILL BECOME MORE WESTERLY TO NORTHWESTERLY...WITH MULTIPLE WEAK UPPER LEVEL DISTURBANCES AND ASSOCIATED FRONTS TRAVERSING THE LOCAL AREA THROUGH NEXT WEEKEND. WHILE SOME VERY LIGHT PRECIPITATION CANNOT BE RULED OUT FOR TIME TO TIME...ESPECIALLY THURSDAY AND AGAIN SATURDAY THROUGH SUNDAY...NO SIGNIFICANT PRECIPITATION ACCUMULATIONS ARE EXPECTED AS THERE WILL BE LIMITED MOISTURE TO WORK WITH. THE MAIN PIECE OF GOOD NEWS IS THAT WITH THE MORE WESTERLY FLOW PATTERN...TEMPERATURES SHOULD MODIFY CLOSER TO...OR EVEN ABOVE...SEASONAL NORMS WEDNESDAY AFTERNOON ONWARD...AND ANY PRECIPITATION THAT DOES MANAGE TO FORM WILL BE IN THE FORM OF LIGHT RAIN OR EVEN JUST SPRINKLES. LATE IN THE UPCOMING WEEKEND AND JUST BEYOND...MODEL DISCREPANCY GROWS AND THE 00Z EC CONTINUES TO BRING A VERY STRONG ARCTIC FRONT ACROSS THE LOCAL AREA...WITH 850MB TEMPS DROPPING TO -16C ACROSS THE LOCAL AREA...WHILE THE GFS MAINTAINS A MUCH MILDER AIRMASS ACROSS THE LOCAL AREA...KEEPING THE COLDER AIRMASS FURTHER EAST. GIVEN THAT THE EC APPEARS TO BE AN OUTLIER AT THIS POINT...WITH THE UPPER LEVEL PATTERNS OF THE GFS ENSEMBLES...UKMET AND GEM LOOKING MORE SIMILAR TO THE GFS...PLENTY OF UNCERTAINTY REMAINS...SO WILL NEED TO CONTINUE TO MONITOR THIS TIME PERIOD AS A RETURN TO UNSEASONABLY COLD TEMPERATURES IS POSSIBLE JUST BEYOND THE CURRENT SCOPE OF THE EXTENDED FORECAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1120 PM CST SUN NOV 10 2013 A COLD FRONT WILL MOVE THROUGH THE KGRI TERMINAL AREA JUST BEFORE SUNRISE ON MONDAY MORNING. ALONG WITH THE COLD FRONT THERE WILL BE SOME MVFR CEILINGS THAT WILL MOVE INTO THE AREA. GUSTY NORTH WINDS ARE EXPECTED. BY EVENING THE WINDS WILL DIMINISH AND CEILINGS WILL LIFT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...SAR AVIATION...JCB
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1147 PM CST SUN NOV 10 2013 .AVIATION... FOR THE 06Z TAFS...MONITORING FOR THE DEVELOPMENT OF FOG THROUGH MONDAY MORNING IS THE PRIMARY AVIATION WEATHER CONCERN OVER THE NEXT 24 HOURS. THE TIMING OF A STRONG COLD FRONT EXPECTED TO MOVE INTO NORTH TEXAS EARLY TUESDAY MORNING WAS PLACED AT THE END OF THE DFW TAF. LOW LEVEL CLOUD COVER HAD CLEARED OUT EARLIER THIS EVENING AND WAS SHOWING NO SIGNS OF REDEVELOPMENT ACROSS THE AREA AT 0530Z. CLEAR SKIES ALLOWED TEMPERATURES TO DROP FASTER THAN EXPECTED LATE THIS EVENING...BRINGING 11 PM/05Z TEMPERATURES DOWN TO WITHIN A FEW DEGREES OF OBSERVED DEW POINTS ACROSS MUCH OF NORTH TEXAS. TEMPERATURES ARE LIKELY TO FALL CLOSE TO THIS AFTERNOONS DEW POINTS WHICH TYPICALLY REPRESENT THE CROSSOVER TEMPERATURE WHEN CONCERNED WITH RADIATIONAL FOG FORECASTING. BASED ON OUR 00Z RAOB AND RAP FORECAST SOUNDINGS TONIGHT...LOW- LEVEL MOISTURE DECREASES WITH HEIGHT...SO DO NOT EXPECT AREAS OF DENSE FOG TO DEVELOP NEAR AREA TAF SITES THROUGH EARLY MONDAY MORNING. REGARDLESS...SOME SHALLOW GROUND FOG IS LIKELY NEAR ALL AREA TAF SITES...SO WENT AHEAD WITH MVFR VSBYS MENTIONED IN THE 10-15Z WINDOW FOR THE DFW AREA...AND 08 TO 15Z WINDOW FOR WACO WITH THESE TAFS. IT IS POSSIBLE THAT THE DECREASE IN MOISTURE WITH HEIGHT IS TOO GREAT TO ALLOW FOR FOG TO DEVELOP...AND IF THAT IS THE CASE FOG CAN BE REMOVED IN THE 09Z AMENDMENTS. IT IS ALSO POSSIBLE THAT VSBYS MAY FALL TO IFR AT TIMES IF FOG DEVELOPS AS LIGHT WINDS MAY LOCALLY INCREASE THE DEPTH OF THE SHALLOW FOG. AT THIS POINT WILL HAVE TO MONITOR AND ADJUST THE TAFS AS NECESSARY TO GAUGE IMPACTS TO THE MORNING FLIGHT SCHEDULE. AS MENTIONED ABOVE...MENTIONED THE PASSAGE OF A STRONG COLD FRONT AT THE END OF THE DFW TAF. THIS FRONT IS EXPECTED TO MOVE THROUGH THE AREA EARLY TUESDAY MORNING...MOVING ACROSS DFW BY 10Z. CAVANAUGH && .PREV DISCUSSION... /ISSUED 311 PM CST SUN NOV 10 2013/ STRATUS CONTINUES TO SLOWLY ERODE FROM EAST TO WEST OVER THE AREA AND MOST OF THE REGION WILL BE CLEAR BY THE EVENING HOURS. STRATUS WILL TEND TO REDEVELOP FROM WEST TO EAST...LIKELY ENCOMPASSING THE WESTERN ZONES BY MIDNIGHT AND REACHING THE I-35 CORRIDOR BEFORE SUNRISE. AS A RESULT...RADIATIONAL COOLING WILL BE FAIR TO GOOD ACROSS THE CENTRAL AND EASTERN ZONES TONIGHT WHERE LOW TEMPS WILL DROP DOWN INTO THE LOW TO MID 40S...WITH THE EXCEPTION OF THE URBAN HEAT ISLAND AROUND THE METROPLEX. MOISTURE DEPTH LOOKS A BIT TOO SHALLOW FOR FOG TONIGHT...BUT WOULD NOT BE SURPRISED TO SEE SOME GROUND FOG ACROSS THE NORTHEAST ZONES. CLOUDS SHOULD HAVE AN EASIER TIME ERODING MONDAY WITH PARTLY SUNNY CONDITIONS EXPECTED BY AFTERNOON. HIGHS SHOULD REACH THE LOW 70S FOR MOST AREAS. THE STRONG COLD FRONT WILL ARRIVE EARLY TUESDAY MORNING. HOWEVER WINDS WILL SHIFT TO THE NORTH SOME 3 TO 6 HOURS AHEAD OF THE TRUE FRONTAL PASSAGE. TEMPERATURES WILL DROP STEADILY INTO THE 50S DURING THE EARLY MORNING HOURS COMPLIMENTS OF RADIATIONAL COOLING AND WEAK COLD ADVECTION. THE TRUE FRONT WILL MOVE THROUGH AROUND OR JUST AFTER SUNRISE OVER THE NORTHERN ZONES AND AROUND MID TO LATE MORNING IN THE SOUTHERN ZONES. TEMPERATURES BEHIND THIS FRONT WILL DROP INTO THE 40S WITH SKIES CLOUDING OVER. LOW LEVEL MOISTURE TRAPPED BELOW THE FRONTAL INVERSION WILL RESULT IN POST FRONTAL CLOUDS AND SOME ISOLATED SHOWERS OR SPRINKLES TUESDAY MORNING. SKIES SHOULD CLEAR FROM NORTH TO SOUTH DURING THE MID AFTERNOON TO EVENING HOURS. WINDS AT 15 TO 25 MPH WILL PUT WIND CHILLS TUESDAY AFTERNOON/EVENING IN THE 30S FOR MOST OF THE AREA. HIGH PRESSURE WILL RAPIDLY BUILD INTO THE REGION TUESDAY NIGHT WITH WINDS BECOMING NEARLY CALM OVER THE NORTHWEST ZONES. LOWS THERE WILL DIP INTO THE LOW TO MID 20S. OTHERWISE EXPECT LOWS TO RANGE FROM THE UPPER 20S TO LOWER 30S WITH ALL BUT THE FAR SOUTHEAST ZONES EXPERIENCING THEIR FIRST FREEZE BY WEDNESDAY MORNING. THE FREEZE WARNING WILL LIKELY BE ISSUED MONDAY AFTERNOON. THE CORE OF THE COLD AIRMASS WILL BE OVERHEAD WEDNESDAY AFTERNOON WITH GENERALLY LIGHT WINDS AND SOME CIRRUS CLOUD COVER EXPECTED. HIGHS WILL STRUGGLE TO WARM...AND MOST AREAS WILL STAY IN THE 40S. BY WEDNESDAY NIGHT THE SURFACE RIDGE WILL MOVE EAST WITH SOUTH WINDS RETURNING AND INCREASING HIGH CLOUDS LIMITING RADIATIONAL COOLING OVER THE WESTERN AND CENTRAL ZONES. THE EASTERN ZONES WILL BE THE COLDEST...AND THE SOUTHEAST ZONES WILL HAVE A SHOT AT A FIRST FREEZE IF THEY MISS OUT WEDNESDAY MORNING. CLOUDS AND MOISTURE WILL INVADE THE AREA THURSDAY AS A SHORTWAVE TROUGH MOVES OVER THE REGION THURSDAY NIGHT. MODEL GUIDANCE IS SHOWING ENOUGH MOISTURE AND INSTABILITY FOR ELEVATED SHOWERS...MUCH OF WHICH WILL BE VIRGA INITIALLY...BUT ENOUGH COLUMN SATURATION SHOULD OCCUR BY THURSDAY AFTERNOON AND EVENING FOR THIS TO REACH THE SURFACE. HAVE ADDED SLIGHT CHANCES OF RAIN THURSDAY AFTERNOON AND WILL CONTINUE THESE LOW POPS INTO THURSDAY NIGHT. THE FORECAST HIGHS THURSDAY MAY END UP BEING TOO WARM...BUT HAVE GONE COLDER THAN ALL OF THE GUIDANCE WITH LOW TO MID 50S. MEANWHILE...WITH CLOUDS AND SOUTHERLY FLOW CONTINUING INTO THURSDAY NIGHT...EXPECT TEMPS TO BE NEARLY STEADY. HAVE RAISED THESE INTO THE MID TO UPPER 40S TO ACCOUNT FOR THIS. ANOTHER STRONGER SHORTWAVE TROUGH WILL APPROACH THE AREA FRIDAY AND MOVE THROUGH THE REGION SATURDAY. WARM ADVECTION WILL CONTINUE WITH SURFACE TEMPS CONTINUING TO GRADUALLY MODERATE...POSSIBLY EVEN RISING DURING THE NIGHT FRIDAY NIGHT. THERE IS ENOUGH INSTABILITY FOR THUNDERSTORMS BY FRIDAY NIGHT AND POPS OF 30 TO 40 PERCENT LOOK GOOD BEFORE THE SYSTEM CLEARS US FROM WEST TO EAST ON SATURDAY. TEMPS BY SATURDAY SHOULD BE IN THE 60S OR 70S. THE ECMWF CONTINUES TO HOLD MORE UPPER LEVEL ENERGY BACK TO THE WEST THIS WEEKEND...WHICH WOULD RESULT IN CONTINUED CLOUD COVER...RAIN CHANCES...AND WARM SOUTHERLY WINDS INTO SUNDAY AND MONDAY. THE GFS SAYS IS WEAKER WITH THIS ENERGY AND IS DRIER. WILL CONTINUE TO SIDE WITH THE ECMWF AND FEATURE LOW POPS IN THE FORECAST AS IT HAS PROVED TO BE SUPERIOR TO THE GFS LATELY. OTHERWISE ANOTHER STRONG COLD FRONT WITH FREEZING TEMPERATURES LOOKS LIKELY BY MONDAY OR TUESDAY OF NEXT WEEK. TR.92 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 50 71 44 51 31 / 0 0 10 10 0 WACO, TX 46 71 51 57 31 / 0 0 5 10 0 PARIS, TX 44 69 45 50 26 / 0 0 10 10 0 DENTON, TX 45 71 41 50 24 / 0 0 20 10 0 MCKINNEY, TX 42 70 43 52 26 / 0 0 10 10 0 DALLAS, TX 50 71 45 52 31 / 0 0 10 10 0 TERRELL, TX 45 71 46 53 30 / 0 0 10 10 0 CORSICANA, TX 46 72 51 55 31 / 0 0 10 10 0 TEMPLE, TX 46 72 51 59 32 / 0 0 5 10 0 MINERAL WELLS, TX 48 71 43 50 26 / 0 0 20 10 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1144 PM CST SUN NOV 10 2013 .AVIATION... KLBB DEWPOINT DEPRESSION NEAR ZERO THIS HOUR AND VERY CLOSE TO DEVELOPING STRATUS LAYER. WE EXPECT LIFR CONDITIONS THROUGH MUCH OF THE NIGHT AT KLBB...LIFTING SLIGHTLY NEAR DAYBREAK...THEN BREAKING SWIFTLY BY MID-MORNING AS DRIER SOUTHWEST COMPONENT PREVAILS. AT KCDS...THE CLOUD LAYER JUST WEST IN THE MID TO UPPER IFR CIG HEIGHT RANGE IS MORE LIKELY TO FILL BACK EAST TO KCDS IN THE NEXT FEW HOURS THAN SURFACE SATURATION BASED ON PERSISTENT TRENDS IN THE RAP THIS EVENING. CIG AT KCDS SHOULD SLOWLY LIFT EARLY MONDAY BEFORE BREAKING UP CLOSE TO MIDDAY. NEXT ON THE HORIZON WILL BE THE SHARP CANADIAN COLD FRONT SURGING SOUTHWARD TIMED PER LATEST WRF/NAM TO KCDS NEAR 04Z AND KLBB NEAR 06Z. RMCQUEEN && .PREV DISCUSSION... /ISSUED 1008 PM CST SUN NOV 10 2013/ UPDATE... AREAS OF DENSE FOG ARE EXPECTED TO FORM RAPIDLY LATE THIS EVENING INTO THE EARLY MORNING HOURS. MOST FAVORED AREA INITIALLY ACROSS THE SOUTH-CENTRAL AND SOUTHEAST PANHANDLE INTO THE NORTHERN SOUTH PLAINS SHOULD EXPAND SOUTH-SOUTHWESTWARD BY OR SHORTLY AFTER MIDNIGHT THROUGH MUCH OF THE SOUTH PLAINS COUNTY. DENSE FOG ADVISORY ISSUED VALID UNTIL 9 AM MONDAY. RMCQUEEN AVIATION... EARLIER TAF PACKAGE CONTINUED TO INDICATE DEVELOPMENT OF AN LIFR STRATUS LAYER AT KLBB CLOSE TO OR SHORTLY AFTER MIDNIGHT AND LASTING UNTIL NEAR OR JUST AFTER DAYBREAK MONDAY. CONDITIONS AT KCDS WILL REMAIN MOSTLY NEAR IFR/MVFR BREAK-OFF UNTIL LIFTING LATE MONDAY MORNING. RMCQUEEN PREV DISCUSSION... /ISSUED 257 PM CST SUN NOV 10 2013/ SHORT TERM... LOW CLOUDS WERE FINALLY RETREATING NORTHWARD...THOUGH THE NORTHEAST ZONES WILL NOT HAVE MUCH TIME TO RECEIVE INSOLATION BEFORE THE SUN SETS. IN ADDITION...SCATTERED TO BROKEN LOW CLOUDS WERE ALREADY FILLING IN ACROSS PORTIONS OF THE ROLLING PLAINS AND MAY CONTINUE TO FILL IN ACROSS THE EAST INTO THIS EVENING. ELSEWHERE WE WILL SEE A PERIOD OF CLEAR SKIES. HOWEVER...LIGHT SOUTHERLY BREEZES OVERNIGHT WILL MAINTAIN AND EVEN INCREASE THE SHALLOW MOISTURE ALREADY IN PLACE...AND COUPLED WITH RADIATIONAL COOLING...WE WILL SEE ANOTHER BOUT OF LOW CLOUDS AND FOG DEVELOP ACROSS THE AREA. TOUGH TO SAY EXACTLY HOW THICK THE FOG WILL BECOME...BUT WE COULD DEFINITELY SEE AREAS OF DENSE FOG AROUND BY EARLY MONDAY MORNING. WITH THIS IN MIND WE HAVE ADDED FOG TO THE WEATHER GRIDS AND ALSO THE HWO. THINK FOG WILL DEVELOP FIRST WHERE SKIES CLEAR ACROSS THE NORTHERN ZONES /LIKELY THE NORTH-CENTRAL ZONES/...WHERE COOLER TEMPERATURES /AND LOWER T-TD SPREADS/WORK WITH A MAXIMIZED UPSLOPE WIND COMPONENT. FOG COULD DEVELOP ACROSS THIS FAVORED AREA AS EARLY AS 3Z OR SO...WITH THE REMAINDER OF THE CWA AT RISK OF FOG DEVELOPMENT AFTER MIDNIGHT...EVEN AS SURFACE WINDS VEER TO A SOUTHWESTERLY DIRECTION. THE MOIST CONDITIONS WILL LIMIT COOL...WITH LOWS TONIGHT MOSTLY IN THE MID AND UPPER 40S TO LOW 50S...EXCEPT ACROSS THE FAR NORTHWESTERN ZONES WHERE SOMEWHAT LOWER DEWPOINTS MAY ALLOW LOWS TO DIP INTO THE 30S. THE FOG AND STRATUS SHOULD BEGIN TO LIFT/BREAK BY MID TO LATE MORNING ON MONDAY...WITH MUCH OF THE FA EXPECTED TO SEE A SUBSTANTIAL AMOUNT OF SUN IN THE AFTERNOON. OBVIOUSLY THE EXACT DURATION/COVERAGE OF THE CLOUD COVER WILL DICTATE HOW WARM WE GET...BUT HAVE MAINTAINED HIGHS IN THE LOWER TO MIDDLE 70S AREA WIDE. BIG CHANGES WILL FOLLOW THOUGH AS A STRONG COLD FRONT WILL MOVE IN TOMORROW NIGHT AS THE QUASI-ZONAL FLOW ALOFT VEERS IN ADVANCE OF A RIDGE AMPLIFYING ACROSS THE WESTERN PART OF THE CONTINENT. LONG TERM... COLD AIR THAT WILL BE MOVING THROUGH THE FCST AREA MONDAY NIGHT HAS BEEN LET LOOSE FROM THE PRAIRIE PROVINCES INTO THE NRN PLAINS...ALMOST TO SOUTH DAKOTA AS OF 20Z. PROBABLY NOT MUCH TO SLOW IT SO PREFER THE FASTEST OF THE MODEL SOLUTIONS. GIVEN STRENGTH OF THIS AIR MASS WILL ALSO LEAN TOWARD COLDER END OF MOS GUIDANCE FOR TEMPS FROM MONDAY NIGHT THROUGH TUESDAY NIGHT. UPPER PATTERN CONTINUES TO SUGGEST MODEL QPF AND MOS POPS ARE OVERDONE. BOTH PLAN VIEWS AND TIME-HEIGHTS SUGGEST BEST BET IS SOME DRIZZLE BEHIND THE FRONT BEFORE DRIER AIR BEGINS TO WORK IN TUESDAY AFTN. SO WILL LOWER POPS SOME AND CONVERT MENTION OF SHOWERS/SPRINKLES TO DRIZZLE WITH A MENTION OF FRZG DRIZZLE ACROSS NRN HALF OF THE FCST AREA WHERE FREEZING TEMPS TUESDAY MORNING ARE LIKELY. HOWEVER...ATTM NO IMPACTS EXPECTED ATTM FROM THE POSSIBLE LIGHT FREEZING PRECIP. MODELS CONTINUE TO EVOLVE MID TO LATE WEEK WITH AN OVERALL PROGRESSIVE PATTERN IN WHAT BECOMES A MORE ZONAL BROADSCALE PATTERN WITH EACH RUN. THAT WOULD HAVE THE EFFECT OF INCREASING TEMPS MORE THAN PREVIOUSLY THOUGHT WITH MEXMOS EXHIBITING THAT TREND ON THE 00Z AND 12Z RUNS. FOR NOW WILL TREND FCST THAT DIRECTION BUT LEAN TOWARD TEMPS OF ENSEMBLE MEAN. PRECIP CHANCES REMAIN LOW DESPITE A SERIES OF LOW-AMPLITUDE SHORT WAVE TROUGHS. IN PART...THE PROGRESSIVE NATURE OF THE FLOW WILL KEEP MEANINGFUL MOISTURE RETURN FROM OCCURRING WHILE THE LOW AMPLITUDE NATURE OF THE TROUGHS SUGGEST FORCING MAY BE LIMITED. IF PRECIP DOES FALL MODELS CONTINUE TO POINT TO FRIDAY AND FRIDAY NIGHT. FOR NOW WILL KEEP THAT PERIOD WITH THE HIGHEST POPS BUT KEEP THEM BELOW 15 PCT AND THUS KEEP PRECIP MENTION OUT OF THE FCST. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 37 73 25 37 23 / 0 0 10 10 0 TULIA 43 70 27 38 22 / 0 0 10 10 0 PLAINVIEW 44 71 28 38 22 / 0 0 10 10 0 LEVELLAND 45 72 31 37 26 / 0 0 10 10 0 LUBBOCK 47 71 31 37 24 / 0 0 10 10 0 DENVER CITY 46 70 34 41 27 / 0 0 10 10 0 BROWNFIELD 46 71 33 37 26 / 0 0 10 10 0 CHILDRESS 48 75 32 41 21 / 0 0 10 10 0 SPUR 49 73 32 39 22 / 0 0 10 10 0 ASPERMONT 52 75 36 40 23 / 0 0 10 10 0 && .LUB WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 9 AM CST MONDAY FOR THE FOLLOWING ZONES: TXZ021>025-027>031-033>036-039>042. && $$ 99/99/05
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
306 AM CST MON NOV 11 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 306 AM CST MON NOV 11 2013 MAIN FORECAST CONCERNS ARE ON LIGHT SNOW TODAY AND TEMPERATURES TONIGHT THROUGH WEDNESDAY. LATEST SURFACE OBSERVATIONS PLACED A COLD FRONT EXTENDING FROM EASTERN LAKE SUPERIOR SOUTHWEST THROUGH NORTH CENTRAL WISCONSIN INTO SOUTHERN MINNESOTA THROUGH SOUTHERN SOUTH DAKOTA...PUSHING SOUTH. AN IMPRESSIVE TEMPERATURE CHANGE BEHIND THE FRONT WITH TEMPERATURES FALLING INTO THE SINGLE DIGITS ACROSS NORTH CENTRAL NORTH DAKOTA. RADAR SHOWED A BAND OF PRECIPITATION SETTING UP FROM CENTRAL WISCONSIN THROUGH SOUTHERN MINNESOTA BACK INTO NORTHERN SOUTH DAKOTA. LIGHT SNOW HAS BEEN REPORTED OVER PORTIONS OF SOUTHERN MINNESOTA INTO SOUTH DAKOTA UNDER THIS BAND. EXPECT THIS BAND TO PROGRESS SOUTH TODAY AND INTENSIFY AS IT APPROACHES THE INTERSTATE 90 CORRIDOR. SNOW ACCUMULATIONS OF A FEW TENTHS TO AROUND AN INCH ARE POSSIBLE WITH THE HIGHER ACCUMULATIONS OCCURRING OVER NORTHEAST IOWA. THE COLD FRONT WILL CONTINUE SLIDING SOUTH ACROSS THE AREA TODAY. A PERIOD LIGHT SNOW IS EXPECTED AS THE FRONT SLIDES THROUGH. MODEL CROSS SECTIONS ORIENTED NORTH/SOUTH ACROSS THE FRONT SHOW FRONTOGENESIS EXTENDING FROM 950 MB THROUGH 700 MB WITH WEAK NEGATIVE EPV NOTED RIGHT AROUND 700 MB. THIS SHOULD PROVIDE ENOUGH SUPPORT FOR A BAND OF LIGHT SNOW. THE BAND WILL PUSH SOUTHWARD ACROSS THE FORECAST AREA TODAY AND FINALLY EXIT THE AREA THIS EVENING. SNOW ACCUMULATIONS WILL RANGE FROM AROUND A TRACE OVER NORTH CENTRAL WISCONSIN TO AROUND ONE INCH ACROSS PORTIONS OF NORTHEAST IOWA. ARCTIC AIR WILL INVADE THE FORECAST AREA TODAY IN THE WAKE OF THE FRONT. 850 MB TEMPERATURES WILL PLUMMET INTO THE -12 TO -15 C RANGE BY LATE THIS AFTERNOON INTO THIS EVENING. THIS IS UNSEASONABLY COLD FOR THIS TIME OF YEAR...WITH 850 MB TEMPERATURE STANDARDIZED ANOMALIES OF -2.0. BREEZY NORTHWEST WINDS OF 15 TO 25 MPH WITH GUSTS TO AROUND 30 MPH WILL MAKE IT FEEL RATHER CHILLY TODAY. PLAN ON TEMPERATURES FALLING THROUGH THE DAY...INTO THE 20S BY THIS AFTERNOON THEN TUMBLING INTO THE TEENS FOR OVERNIGHT LOWS. CANNOT RULE OUT SOME SINGLE DIGIT READINGS OVER NORTH CENTRAL WISCONSIN EARLY TUESDAY MORNING. NORTHWEST WINDS WILL TAPER OFF TONIGHT. HOWEVER SPEEDS OF 5 TO 10 MPH WILL BE COMMON TONIGHT LEADING TO WIND CHILLS IN THE SINGLE DIGITS ABOVE ZERO. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 306 AM CST MON NOV 11 2013 THE ARCTIC HIGH SLIDES ACROSS THE REGION ON TUESDAY PROVIDING SUNNY SKIES AND UNSEASONABLY COOL HIGH TEMPERATURES. HIGH TEMPERATURES ON TUESDAY WILL RANGE FROM THE MID 20S ACROSS NORTH CENTRAL WISCONSIN AND SOUTHEAST MINNESOTA TO AROUND 30S ACROSS NORTHEAST IOWA INTO FAR SOUTHWEST WISCONSIN. THE HIGH THEN SLIDES SOUTHEAST OF THE REGION TUESDAY NIGHT INTO WEDNESDAY AS ZONAL FLOW ALOFT SETS UP OVER THE AREA. TEMPERATURES MORE TYPICAL OF MID NOVEMBER WILL RETURN TO THE REGION ON WEDNESDAY ON THE BACK SIDE OF THE DEPARTING HIGH. 850 MB TEMPERATURES WARM TO AROUND +7 ON WEDNESDAY. HIGH TEMPERATURES ARE EXPECTED TO RANGE FROM THE UPPER 30S TO LOWER 40S. MOISTURE IS VERY SLOW TO RETURN ON WEDNESDAY AND WITH A TIGHT PRESSURE GRADIENT ACROSS THE AREA THERE COULD BE SOME FIRE WEATHER CONCERNS. AFTERNOON RELATIVE HUMIDITY VALUES ARE EXPECTED TO DROP INTO THE UPPER 20S. THESE RELATIVE HUMIDITY VALUES COMBINED WITH SOUTHWEST WINDS OF 15 TO 25 MPH COULD LEAD TO HEIGHTENED FIRE DANGER. WILL HAVE TO KEEP A CLOSE EYE ON THIS THE NEXT FEW MODEL RUNS. THE NEXT CHANCE FOR PRECIPITATION WILL ARRIVE ON THURSDAY AS A WEAK SHORTWAVE TROUGH MOVES ACROSS THE REGION. A GRADUALLY WARMING TREND IS IN STORE FOR THE REGION FOR THE END OF THE WORK WEEK INTO THE WEEKEND AS A TROUGH DEVELOPS OVER THE SOUTHWEST CONUS. SOUTHWEST FLOW ALOFT LOOKS TO SET UP ACROSS THE REGION LATE SATURDAY THROUGH SUNDAY. WARMER AIR IS EXPECTED TO ADVECT NORTHWARD INTO THE UPPER MISSISSIPPI RIVER VALLEY FOR THE WEEKEND WITH HIGHS CLIMBING INTO THE UPPER 40S TO LOWER 50S. EMBEDDED SHORTWAVES IN THE SOUTHWEST FLOW ALOFT WILL BRING CHANCES FOR RAIN TO THE REGION. FORECAST MODELS ARE SHOWING SOME DIFFERENCES IN STRENGTH AND TIMING OF THESE FEATURES SO WILL LEAN TOWARD A MODEL CONSENSUS BLEND FOR PRECIPITATION CHANCES NEXT WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1104 PM CST SUN NOV 10 2013 THE COLD FRONT IS MAKING GOOD PROGRESS TO THE SOUTHEAST AND EXTENDS FROM NORTHWEST WISCONSIN INTO SOUTHWEST MINNESOTA LATE THIS EVENING. IT LOOKS TO BE A LITTLE FASTER THAN PREVIOUSLY THOUGHT SO HAVE MOVED THE WIND SHIFT UP AN HOUR FOR BOTH SITES. THE QUESTION THEN BECOMES WHETHER THE LOW CLOUDS AND LIGHT SNOW ARE GOING TO FORM BEHIND THE FRONT. STARTING TO SEE A FEW SITES REPORTING SOME MVFR CEILINGS ACROSS NORTHERN INTO WESTERN MINNESOTA. WITH THE 11.00Z NAM AND 11.03Z RAP CONTINUING TO SHOW THE LOW LEVELS BECOMING SATURATED BEHIND THE FRONT...WILL CONTINUE THE TREND OF BRINGING IN MVFR CEILINGS FOR A FEW HOURS. THE NAM CAME IN A LITTLE STRONGER WITH THE FRONTOGENESIS IN THE 850-700 MB LAYER THAN THE 10.18Z RUN AND NOW SPITS OUT SOME LIGHT QPF ACROSS THE AREA. THE NAM ALSO CAME IN STRONGER WITH THE PV ADVECTION IN THE 500-300 MB LAYER WITH A STRETCHED OUT SECONDARY SHORT WAVE TROUGH IT BRINGS ACROSS THE AREA AS THE MAIN SHORT WAVE TROUGH AND UPPER LEVEL LOW STAYS OVER THE GREAT LAKES INTO ONTARIO. LOOKING AT THE BUFKIT SOUNDINGS...CONCERNED THAT THIS FORCING MAY BE TOO WEAK TO PRODUCE MUCH BEYOND FLURRIES OR SOME VERY LIGHT SNOW. THE OMEGA IN THE LOW LEVELS IS PRETTY WEAK WITH THE STRONGER LIFT IN THE MID LEVELS. FOR NOW...WILL MAINTAIN THE MVFR VISIBILITY WITH SOME LIGHT SNOW WITH THE LOW CEILINGS. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE FRONT TO ALLOW GUSTY WINDS TO SPREAD ACROSS THE AREA AND THESE THEN LOOK TO REMAIN THROUGH ALL OF MONDAY UNTIL SUNSET WHEN THE INVERSION SHOULD DEVELOP AND CUT OFF THE MIXING. THE CEILINGS SHOULD GO BACK UP TO VFR BY MID MORNING AS THE BAND OF LOW LEVEL MOISTURE MOVES SOUTH OF THE AREA. THE CLOUDS WILL LIKELY SCATTER/CLEAR OUT FASTER THAN THE TREND IN THE FORECAST...BUT DID NOT HAVE ANY OTHER CHANGES TO JUSTIFY ADDING A VFR CHANGE GROUP SO SHOWED THIS HAPPENING WHEN THE WINDS DIMINISH. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...WETENKAMP LONG TERM...WETENKAMP AVIATION...04
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1130 PM CST SUN NOV 10 2013 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .UPDATE... ISSUED AT 953 PM CST SUN NOV 10 2013 CONCERNED ABOUT A POSSIBLE HIGH-IMPACT SUB-ADVISORY (HISA) EVENT LATE TONIGHT INTO EARLY MONDAY. SNOWFALL SHOULD NOT BE A SIGNIFICANT PROBLEM...AS ACCUMS SHOULD BE AN INCH OR LESS IN MOST AREAS. HOWEVER... ROADS THAT ARE WET FROM RAIN OR MELTING SNOW WILL QUICKLY ICE UP AS ARCTIC AIR ARRIVES. ISSUED AN SPS AND UPDATED THE HWO TO GET THE WORD OUT. && .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 230 PM CST SUN NOV 10 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE HIGH PRESSURE MOVING SOUTHEAST ACROSS THE MID-MISSISSIPPI VALLEY AND LOW PRESSURE DIVING SE ACROSS NORTHWEST ONTARIO. ATTACHED TO THE SURFACE LOW IS AN ARCTIC COLD FRONT WHICH IS PUSHING INTO THE NORTHERN PLAINS. LOW STRATO-CU ACROSS THE NORTH IS FINALLY EXITING NORTHEAST WISCONSIN AT THE MOMENT...BUT MID AND HIGH CLOUDS ARE ALREADY MOVING INTO THE STATE. AS A RESULT...CLOUDS WILL BE ON THE INCREASE FOR THE REST OF THE AFTERNOON. BUT QUICKLY ATTENTION WILL TURN TO THE ARCTIC FRONT. SNOW SHOWERS ARE OCCURRING ALONG THE FRONT OVER SOUTHWEST ONTARIO AND FAR NORTHERN MINNESOTA...DROPPING VSBYS TO 1 1/2SM. TEMPERATURES ARE FALLING BEHIND THE FRONT INTO THE SINGLE DIGITS AND TEENS ACROSS MANITOBA. WITH THE FRONT ARRIVING TONIGHT...SNOW CHANCES/ACCUMS AND TEMPERATURES TOMORROW ARE THE MAIN FORECAST CONCERNS. TONIGHT...A STRONG SHORTWAVE TROUGH WILL DIVE SOUTHEAST ACROSS ONTARIO...WITH THE TAIL END OF THE VORT PASSING ACROSS LAKE SUPERIOR AND THE UPPER PENINSULA. THIS SHORTWAVE WILL PUSH AN ARCTIC FRONT INTO FAR NORTH-CENTRAL WISCONSIN BY 06Z AND ACROSS THE REST OF THE FORECAST AREA OVERNIGHT. FORCING IS VERY GOOD ALONG THE FRONT...WITH STRONG CONVERGENCE...AND DECENT MID-LEVEL FGEN AND -DIVQ. MOISTURE TRANSPORT AND ISENTROPIC ASCENT AHEAD OF THE FRONT IS ON THE WEAKER SIDE THOUGH...AND THINK THE NAM MAY BE A LITTLE TOO AMBITIOUS IN GENERATING PRECIP AHEAD OF THE FRONT. BUT SHOULD SEE A BKN BAND OF PRECIP RIGHT AHEAD OF THE FRONT THOUGH. BUFKIT SOUNDINGS INDICATE THAT LOW WET BULB TEMPS SHOULD KEEP PTYPE AS MOSTLY SNOW OVER CENTRAL AND NORTHEAST WISCONSIN...WHILE PRECIP WILL LIKELY START OUT AS RAIN OVER EAST-CENTRAL WISCONSIN. THEN PRECIP WILL CHANGE TO SNOW AS COLDER AIR FILTERS SOUTH. COULD SEE A DUSTING OVER THE SOUTHEAST FORECAST AREA. MAX OMEGA WILL RESIDE IN THE DENDRITIC GROWTH ZONE...WHICH SUGGESTS THAT SNOWFALL RATES MAY BECOME BRIEFLY INTENSE WITHIN THE STRONGER SNOW SHOWERS ACROSS THE NORTH. BECAUSE THE SNOW SHOWERS WILL LIKELY BE FAST MOVING...TOUGH TO SEE MUCH MORE THAN AN INCH OF ACCUMULATION. LOWS FALLING INTO THE LOWER 20S NORTH...BUT ONLY FALLING INTO THE LOWER 30S SOUTHEAST. MONDAY...ARCTIC AIR WILL QUICKLY FLOOD SOUTHEAST ACROSS THE FORECAST AREA DURING THE MORNING...AND TEMPS WILL NOT RISE VERY MUCH OFF THE MORNING LOWS. MAY ACTUALLY SEE TEMPS FALL A BIT DURING THE MORNING OVER EAST-CENTRAL WISCONSIN. THOUGH THE AIRMASS IS VERY DRY BEHIND THE FRONT...SHOULD STILL SEE SCATTERED LAKE EFFECT SNOW SHOWERS ACROSS N-C WISCONSIN DURING THE MORNING WHICH SHOULD NOT AMOUNT TO MUCH ACCUMULATION. MAY SEE THE SNOW SHOWERS PARTIALLY DIMINISH IN THE AFTERNOON AS THE DRY AIR ASSERTS ITS INFLUENCE. A FEW LIGHT SNOW SHOWERS MAY ALSO LINGER ACROSS EAST-CENTRAL WISCONSIN EARLY IN THE MORNING RIGHT BEHIND THE FRONT. NORTHWEST WINDS WILL BE BREEZY...AND SHOULD LEAD TO APPARENT TEMPS FALLING INTO THE SINGLE DIGITS AND TEENS...DESPITE SOME SUNSHINE. MORNING HIGHS IN THE MID 20S NORTH TO MID 30S SOUTHEAST. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 230 PM CST SUN NOV 10 2013 MODELS IN GENERAL AGREEMENT ON OVERALL PATTERN CHANGE EXPECTED DURING THIS PERIOD AS WEST UPPER RIDGE/EAST TROF TRANSITIONS TO WESTERN TROF AND EASTERN RIDGE. OVERALL...LITTLE CHANGE TO THIS PERIOD. LINGERING LAKE EFFECT SNOW SHOWERS OR FLURRIES IN THE LK SUPERIOR SNOWBELT EARLY IN PERIOD...BUT WINDS BACK QUICKLY ENDING THREAT. WARM AIR ADVECTION ON BACKSIDE OF RETREATING ARCTIC RIDGE AT THE SURFACE...ENHANCED BY LIFT FROM WEAK WAVE PRODUCES A PERIOD OF LIGHT PRECIPITATION...MAINLY RAIN...LATE THU INTO EARLY FRI. AS RIDGE MOVES OFF EAST COAST...DEEPER MOISTURE INFLUX NOTED. ANOTHER WAVE IN SW FLOW PRODUCES LARGER AREA OF RAIN...CLIPPING THE EASTERN 2/3RDS OF WISCONSIN NEXT WEEKEND. SW FLOW WILL USHER IN MILDER TEMPS AFTER TUE...WITH TEMPS ABOVE NORMS BY END OF WEEK. TEMP FORECAST A BLEND OF BEST PERFORMING GUIDANCE. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1119 PM CST SUN NOV 10 2013 A STRONG ARCTIC COLD FRONT WILL MOVE THROUGH THE FORECAST AREA OVERNIGHT INTO EARLY MONDAY...BRINGING GUSTY NW WINDS...FALLING TEMPS AND SOME LIGHT SNOW. RAIN WILL BE POSSIBLE EARLY IN THE TAF PERIOD AT ATW/GRB. THE SNOW WILL BE HEAVIEST WHEN THE FRONT MOVES THROUGH...WITH VSBYS DROPPING TO AS LOW AS 1SM-2SM. MVFR/IFR CONDITIONS WILL OCCUR WITH THE SNOW...AND SOME MVFR CIGS WILL LINGER OVER THE REGION FOR A WHILE MONDAY MORNING. LAKE-EFFECT SNOW SHOWERS AND ASSOCIATED MVFR CONDITIONS SHOULD CONTINUE OVER NC WI THROUGH THE DAY...WHILE THE REST OF THE REGION SEES AN IMPROVEMENT TO VFR CONDITIONS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........KIECKBUSCH SHORT TERM.....MPC LONG TERM......JKL AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1104 PM CST SUN NOV 10 2013 .SHORT TERM...(TONIGHT AND TUESDAY) ISSUED AT 230 PM CST SUN NOV 10 2013 AN UPPER LEVEL TROUGH WILL SWEEP EASTWARD ACROSS SOUTHEAST CANADA TONIGHT/MONDAY. ITS ASSOCIATED COLD FRONT WILL SAG SOUTHWARD THROUGH THE UPPER MISSISSIPPI RIVER VALLEY OVERNIGHT...ALREADY SOUTH OF THE FORECAST AREA BY 12Z. TWO CONCERNS WITH THIS FRONT...JUST HOW COLD IT WILL GET AND IF THERE WILL BE ANY CHANCE FOR PCPN. FIRST...SIGNIFICANTLY COLDER AIR WILL FOLLOW IN THE WAKE OF THE FRONT. 850 MB TEMPS PROGGED TO DROP FROM AROUND 3 C AT 00Z TONIGHT TO -13 C BY 00Z SUN EVENING. 850 MB TEMP SREF ANOMALIES ARE AROUND -1.5 MON-TUE. HIGHS FOR MONDAY WILL LIKELY BE THE MIDNIGHT TEMPERATURE TONIGHT...WITH SLOWLY FALLING TO STEADY TEMPERATURES THE REST OF THE DAY. HIGH PRESSURE DROPS ACROSS THE NORTHERN PLAINS SUNDAY NIGHT...RESULTING IN CLEAR/PARTLY CLOUDY SKIES FOR MOST OF THE REGION. THE FORECAST AREA IS STILL UNDER A SFC PRESSURE GRADIENT THOUGH...KEEPING WINDS UP A BIT...AND THUS NOT AN IDEAL RADIATIONAL COOLING NIGHT. STILL...TEMPERATURES WILL TUMBLE AND EXPECTING THE COLDEST MORNING OF THE SEASON. TUE WILL FEEL MORE LIKE MID DECEMBER RATHER THAN EARLY NOV. SECOND...FOR PCPN...THE BULK OF THE UPPER LEVEL ENERGY STAYS WELL NORTH...BUT THERE IS SOME ELONGATED PIECES OF ENERGY THAT STRETCH WESTWARD ALONG THE LEADING EDGE OF THE TROUGH...TRAILING THE SFC COLD FRONT. A NORTH-SOUTH RUNNING X-SECTION VIA THE GFS AND NAM SHOW A DECENT SLOPING FRONTOGENETIC RESPONSE WITH THE FRONT...STRONGEST POST THE FRONT BETWEEN 12-18Z. SOME SLOPING QG CONVERGENCE ALSO WITH THE SYSTEM...WHILE ALL THE WARM AIR ADVECTION/ISENTROPIC UPGLIDE IS AHEAD OF THE FRONT...AND THUS SOUTH OF THE FORECAST AREA BY 12Z. SOME HINTS OF HELP WITH LIFT FROM THE 300 MB JET...MOSTLY FOR NORTHEAST WI OVERNIGHT. PLENTY OF LIFT FOR PCPN...BUT HOW MUCH SATURATION IT WILL HAVE TO WORK WITH BRINGS A LOT OF QUESTION MARKS. THE NORTH-SOUTH X-SECTIONS POINT TO A SMALL WINDOW OF DEEPER SATURATION...ALONG AND BEHIND THE FRONT. THE COLDER/DRIER PUSH OF LOW/MID LEVEL AIR QUICKLY DRIVES INTO THE SATURATION...LIKELY PROVIDING AN EFFECTIVE DETERRENT TO ANYTHING REACHING THE GROUND. BUT THERE IS A 3-4 HOUR WIND WHERE EVERYTHING COMES TOGETHER AND LIGHT/VERY LIGHT PCPN WOULD BE LIKELY. BUFKIT SOUNDINGS SUPPORT SNOW. DON/T SEE MUCH IF ANY ACCUMULATION...WITH MINIMAL QPF IN LATEST MODEL RUNS AND SREF PROBABILITIES. IT COULD END UP BEING A FEW HOUR PERIOD OF FLURRIES/VERY LIGHT SNOW WITH ONLY TRACE ACCUMULATIONS TO A TENTH OR TWO. THE EARLY/MID MORNING TIME FRAME WOULD BE FAVORED BASED ON CURRENT TIMING VIA THE GFS/NAM/EC. ONE CAVEAT TO POINT OUT FOR THE PCPN CHANCES TONIGHT. SOME MESO MODELS SUGGEST SOME LIGHT PCPN COULD COME OUT OF THE MASS OF MID LEVEL CLOUDS MOVING IN FROM THE WEST. THIS WOULD BE TRIGGERED BY INCREASING ISENTROPIC UPGLIDE ALONG WITH SOME 850 MB MOISTURE TRANSPORT. CHANCES WOULD STAY MOSTLY EAST OF THE MISSISSIPPI RIVER. CONFIDENCE LOW AT THIS TIME...SO WILL NOT ADD TO THE FORECAST. IF IT WOULD OCCUR...PROBABLY ONLY SPRINKLES. TRENDS WILL HAVE TO BE MONITORED. .LONG TERM...(WEDNESDAY THROUGH SUNDAY) ISSUED AT 230 PM CST SUN NOV 10 2013 GFS/ECMWF IN GOOD AGREEMENT WITH SHIFTING THE UPPER LEVEL PATTERN TO MORE ZONAL BY THE MIDDLE OF NEXT WEEK...WITH A MORE PERSISTENT SOUTHWEST TO WESTERN FLOW OF AIR. TEMPERATURES WILL MODERATE BACK TO THE SEASONABLE NORMALS...PERHAPS EVEN A FEW DEGREES ABOVE NORMAL. THE BULK OF THE SHORTWAVE ACTIVITY IN THE FLOW WILL STAY NORTH OR SOUTH OF THE REGION. HOWEVER...THE GFS AND EC BOTH FAVOR SWINGING A PIECE OF UPPER LEVEL ENERGY FROM THE SOUTHERN PLAINS NORTHEAST ACROSS THE GREAT LAKES SAT/SUN. WHILE THE BRUNT OF THE PCPN CHANCES WITH THIS FEATURE WOULD CURRENTLY STAY SOUTH/EAST OF THE FORECAST AREA...ITS TRACK WOULD BE CLOSE ENOUGH TO BRING AT LEAST A SMALL THREAT FOR SOME SHOWERS. COULD BE RAIN OR SNOW DEPENDING ON TIMING. THE GFS IS THE PERKIER OF THE MODELS. WILL STICK WITH CONSENSUS SOLUTION FOR CHANCES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1104 PM CST SUN NOV 10 2013 THE COLD FRONT IS MAKING GOOD PROGRESS TO THE SOUTHEAST AND EXTENDS FROM NORTHWEST WISCONSIN INTO SOUTHWEST MINNESOTA LATE THIS EVENING. IT LOOKS TO BE A LITTLE FASTER THAN PREVIOUSLY THOUGHT SO HAVE MOVED THE WIND SHIFT UP AN HOUR FOR BOTH SITES. THE QUESTION THEN BECOMES WHETHER THE LOW CLOUDS AND LIGHT SNOW ARE GOING TO FORM BEHIND THE FRONT. STARTING TO SEE A FEW SITES REPORTING SOME MVFR CEILINGS ACROSS NORTHERN INTO WESTERN MINNESOTA. WITH THE 11.00Z NAM AND 11.03Z RAP CONTINUING TO SHOW THE LOW LEVELS BECOMING SATURATED BEHIND THE FRONT...WILL CONTINUE THE TREND OF BRINGING IN MVFR CEILINGS FOR A FEW HOURS. THE NAM CAME IN A LITTLE STRONGER WITH THE FRONTOGENESIS IN THE 850-700 MB LAYER THAN THE 10.18Z RUN AND NOW SPITS OUT SOME LIGHT QPF ACROSS THE AREA. THE NAM ALSO CAME IN STRONGER WITH THE PV ADVECTION IN THE 500-300 MB LAYER WITH A STRETCHED OUT SECONDARY SHORT WAVE TROUGH IT BRINGS ACROSS THE AREA AS THE MAIN SHORT WAVE TROUGH AND UPPER LEVEL LOW STAYS OVER THE GREAT LAKES INTO ONTARIO. LOOKING AT THE BUFKIT SOUNDINGS...CONCERNED THAT THIS FORCING MAY BE TOO WEAK TO PRODUCE MUCH BEYOND FLURRIES OR SOME VERY LIGHT SNOW. THE OMEGA IN THE LOW LEVELS IS PRETTY WEAK WITH THE STRONGER LIFT IN THE MID LEVELS. FOR NOW...WILL MAINTAIN THE MVFR VISIBILITY WITH SOME LIGHT SNOW WITH THE LOW CEILINGS. STEEP LOW LEVEL LAPSE RATES DEVELOP BEHIND THE FRONT TO ALLOW GUSTY WINDS TO SPREAD ACROSS THE AREA AND THESE THEN LOOK TO REMAIN THROUGH ALL OF MONDAY UNTIL SUNSET WHEN THE INVERSION SHOULD DEVELOP AND CUT OFF THE MIXING. THE CEILINGS SHOULD GO BACK UP TO VFR BY MID MORNING AS THE BAND OF LOW LEVEL MOISTURE MOVES SOUTH OF THE AREA. THE CLOUDS WILL LIKELY SCATTER/CLEAR OUT FASTER THAN THE TREND IN THE FORECAST...BUT DID NOT HAVE ANY OTHER CHANGES TO JUSTIFY ADDING A VFR CHANGE GROUP SO SHOWED THIS HAPPENING WHEN THE WINDS DIMINISH. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RIECK LONG TERM....RIECK AVIATION...04
AREA FORECAST DISCUSSION
NWS HASTINGS NE
523 AM CST MON NOV 11 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM CST MON NOV 11 2013 MAIN FORECAST CONCERNS WILL BE TEMPERATURES AND FOG EARLY THIS MORNING. SURFACE ANALYSIS SHOWS A COLD FRONT ACROSS CENTRAL NEBRASKA AT THIS TIME THAT HAS BEEN STEADILY MOVING TO THE SOUTH ACROSS NORTHERN NEBRASKA EARLY THIS MORNING. SATELLITE SHOWS SOME CLOUDS A WAYS BEHIND THE COLD FRONT. SURFACE OBSERVATIONS HAVE SOME SPOTTY FOG THAT HAS BEEN REDUCING VISIBILITIES TO LESS THAN A MILE AT TIMES. DEW POINTS ACROSS THE AREA ARE FAIRLY HIGH...IN THE UPPER 30S TO MID 40S. AS TEMPERATURES FALL OFF THE VISIBILITY DROPS IN FOG. EXPECT THAT WITH THE LIGHT WINDS AHEAD OF THE FRONT AND THE MOIST AIR THERE WILL BE SOME FOG ACROSS THE AREA EARLY THIS MORNING. AS THE COLD FRONT MOVES SOUTH THE WINDS WILL TURN TO THE NORTH AND START TO INCREASE. THIS SHOULD BRING AN END TO THE FOG THIS MORNING. THE MAIN QUESTION WILL BE HOW WIDESPREAD THE FOG WILL BE AND HOW LOW THE VISIBILITIES WILL DROP. THE HRRR AND SREF BOTH REDUCE VISIBILITIES TO LESS THAN A MILE. WILL START WITH THAT AND WATCH. THE COLD FRONT IS EXPECTED TO BE MOST...IF NOT ALL...OF THE WAY THROUGH THE FORECAST AREA BY SUNRISE THIS MORNING. BEHIND THIS COLD FRONT THERE IS VERY COLD AIR THAT WILL BE PUSHING INTO THE FORECAST AREA. TEMPERATURES ARE NOT LIKELY TO WARM VERY MUCH AT ALL TODAY AND WILL PROBABLY FALL THROUGHOUT THE DAY. CLOUDS WILL PUSH INTO THE FORECAST AREA DURING THE DAY. THERE IS A FAIRLY TIGHT PRESSURE GRADIENT BEHIND THE COLD FRONT AS WELL. WINDS ALOFT REMAIN MAINLY 10 TO 20 KNOTS SO THE WIND SHOULD BE BREEZY WITH 10 TO 20 MPH AND GUSTS TO AROUND 25 MPH OR SO. A COLD HIGH PRESSURE SYSTEM WILL BUILD INTO THE FORECAST AREA TONIGHT. WITH THIS THE WINDS WILL BE LIGHT...SKIES WILL CLEAR OUT AND TEMPERATURES WILL CONTINUE TO DROP THROUGH THE NIGHT. LOW TEMPERATURES IN THE MORNING WILL BE IN THE 5 TO 15 DEGREE RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 353 AM CST MON NOV 11 2013 A STRONG SURFACE HIGH PRESSURE SYSTEM WILL BE NEARLY CENTERED OVER THE FORECAST AREA TO START THE EXTENDED PERIODS...AND IS EXPECTED TO DRIFT SLOWLY SOUTHWEST DURING THE DAY TUESDAY. THEREFORE...WHILE WINDS WILL BE GENERALLY LIGHT AND SHIFTING OUT OF THE OF THE SOUTH DURING THE AFTERNOON HOURS...TEMPERATURES WILL BE ON THE COLD SIDE...AS THE HEART OF THE APPROACHING COLD AIRMASS WILL ENCOMPASS THE ENTIRE FORECAST AREA. AS A RESULT...EXPECTED HIGH TEMPERATURES TUESDAY TO STRUGGLE TO REACH THE MIDDLE 30S ACROSS THE ENTIRE AREA...OR ALMOST 20 DEGREES BELOW NORMAL. TEMPERATURES WILL CONTINUE TO BE THE FOCUS TUESDAY NIGHT...ALBEIT THE AIRMASS WILL HAVE MODIFIED SOME SINCE MONDAY NIGHT THANKS TO SOUTHWESTERLY RETURN FLOW...AND EXPECT TEMPERATURES TO BOTTOM OUT IN THE UPPER TEENS TO LOWER 20S...OR ABOUT 10 DEGREES BELOW NORMAL MID NOVEMBER LOWS. THEREAFTER...THE UPPER LEVEL PATTERN WILL BECOME MORE WESTERLY TO NORTHWESTERLY...WITH MULTIPLE WEAK UPPER LEVEL DISTURBANCES AND ASSOCIATED FRONTS TRAVERSING THE LOCAL AREA THROUGH NEXT WEEKEND. WHILE SOME VERY LIGHT PRECIPITATION CANNOT BE RULED OUT FOR TIME TO TIME...ESPECIALLY THURSDAY AND AGAIN SATURDAY THROUGH SUNDAY...NO SIGNIFICANT PRECIPITATION ACCUMULATIONS ARE EXPECTED AS THERE WILL BE LIMITED MOISTURE TO WORK WITH. THE MAIN PIECE OF GOOD NEWS IS THAT WITH THE MORE WESTERLY FLOW PATTERN...TEMPERATURES SHOULD MODIFY CLOSER TO...OR EVEN ABOVE...SEASONAL NORMS WEDNESDAY AFTERNOON ONWARD...AND ANY PRECIPITATION THAT DOES MANAGE TO FORM WILL BE IN THE FORM OF LIGHT RAIN OR EVEN JUST SPRINKLES. LATE IN THE UPCOMING WEEKEND AND JUST BEYOND...MODEL DISCREPANCY GROWS AND THE 00Z EC CONTINUES TO BRING A VERY STRONG ARCTIC FRONT ACROSS THE LOCAL AREA...WITH 850MB TEMPS DROPPING TO -16C ACROSS THE LOCAL AREA...WHILE THE GFS MAINTAINS A MUCH MILDER AIRMASS ACROSS THE LOCAL AREA...KEEPING THE COLDER AIRMASS FURTHER EAST. GIVEN THAT THE EC APPEARS TO BE AN OUTLIER AT THIS POINT...WITH THE UPPER LEVEL PATTERNS OF THE GFS ENSEMBLES...UKMET AND GEM LOOKING MORE SIMILAR TO THE GFS...PLENTY OF UNCERTAINTY REMAINS...SO WILL NEED TO CONTINUE TO MONITOR THIS TIME PERIOD AS A RETURN TO UNSEASONABLY COLD TEMPERATURES IS POSSIBLE JUST BEYOND THE CURRENT SCOPE OF THE EXTENDED FORECAST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 524 AM CST MON NOV 11 2013 THE COLD FRONT HAS MOVED THROUGH THE KGRI TERMINAL AREA ALREADY THIS MORNING. WINDS WILL START TO INCREASE AND BECOME GUSTY LATER THIS MORNING BEFORE DIMINISHING THIS EVENING. THERE WILL ALSO BE SOME CLOUDS THAT WILL MOVE INTO THE AREA THIS MORNING. THERE COULD BE SOME MVFR CEILINGS FOR A WHILE THIS AFTERNOON. THE CLOUDS WILL DIMINISH AFTER DARK TONIGHT AS A SURFACE HIGH MOVES INTO THE AREA. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...SAR AVIATION...JCB
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
601 AM CST MON NOV 11 2013 UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 428 AM CST MON NOV 11 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY INDICATE STRONG COLD FRONT NOW EXTENDING ACROSS CWA FROM NEAR IMT TO RRL. BEHIND THE FRONT TEMPERATURES DROPPING QUICKLY INTO LOWER TO MIDDLE 20S. NORTHWEST WINDS ALSO QUITE GUSTY BEHIND FRONT. RADAR RETURNS HAVE FILLED IN/EXPANDED MIDNIGHT ONWARD IN RESPONSE TO STRONG FGEN FORCING OVER NORTHERN AND CENTRAL WI. LIGHT SNOW FALLING NORTH OF FRONT...RAIN SOUTH. NO SNOWFALL AMOUNTS REPORTED AS OF YET...THOUGH WEBCAMS FAR NORTH LOOK LIKE GOOD INCH HAS FALLEN SO FAR. MAIN CHANGE IN THIS FORECAST WAS TO SLOW PROGRESSION SLIGHTLY...INCLUDING RAIN TO SNOW CHANGEOVER. FORCING EXPECTED TO DROP SOUTH AND EAST THROUGH AREA THROUGH MID MORNING. HAVE TRIED TO DEPICT TEMP DROP THROUGH THIS MORNING...THEN NEAR STEADY TEMPS THROUGH THE AFTERNOON. WITH SLOWER DROP IN TEMPS OVER FOX VALLEY THIS MORNING...WILL UPDATE SPS SENT OUT EARLIER TO HIGHLIGHT AREAS WEST AND NORTH FOR THE MORNING COMMUTE. HIGH PRESSURE TO DROP SOUTH INTO THE PLAINS TONIGHT AND TUE MAKING CONDITIONS LESS FAVORABLE FOR LES OVER THE NORTH. HAVE STAYED WITH CHANCE/SCATTERED WORDING AND PREVIOUS SNOW AMOUNTS IN THE SNOW BELT FOR TODAY GIVEN DRY AIR AND LOWERING INVERSION HEIGHTS. COLD TEMPS TO CONTINUE THROUGH THE PERIOD WITH APPARENT TEMPS TODAY RUNNING IN THE SINGLE DIGITS NORTH AND TEENS SOUTH. TONIGHT WINDS WILL MAKE IT FEEL LIKE NEAR ZERO NORTH AND SINGLE DIGITS SOUTH. LIGHTER WINDS LATER TUE WILL BRING SOME IMPROVEMENT. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 428 AM CST MON NOV 11 2013 MDLS CONT TO INDICATE THE DEVELOPMENT OF UPR RDGS OVER THE ERN PACIFIC AND WRN ATLANTIC WITH A BROAD UPR TROF OVER THE CNTRL CONUS. MEAN FLOW OVER THE GREAT LAKES WL SWITCH FROM NW TO SW AS THIS UPR TROF DEVELOPS WHICH WL BRING MILDER...BUT MORE UNSETTLED WEATHER TO NE WI TOWARD NEXT WEEKEND. MAIN FCST ISSUE WL BE TRYING TO DETERMINE BEST PERIOD TO MENTION PCPN CHCS AS THE MDLS DIFFER ON WHICH BRANCH OF THE JET WL BECOME MORE DOMINANT. THE SFC RDG AXIS TO EXTEND FROM THE SRN PLAINS NEWD TO SRN SECTIONS OF THE GREAT LAKES TUE NGT. MEANWHILE...A WEAKENING UPR RDG WL BE PUSHING ACROSS THE UPR MS VALLEY TOWARD WI. THIS TRANSLATES TO A QUIET WEATHER PATTERN FOR NE WI UNDER MOSTLY CLR SKIES AND W-SW WINDS UNDER 10 MPH. WEAK WAA TO PERSIST THRU THE NGT AND THIS WL HELP TO COUNTER THE UNSEASONABLY COOL AIR MASS OVERHEAD. MIN TEMPS ARE EXPECTED TO BE CLOSE TO VALUES SEEN MON NGT (GENERALLY TEENS INLAND...AROUND 20 NEAR LAKE MI). INCREASING SW WINDS BETWEEN THE SFC HI OVER THE TN VALLEY AND A SFC LOW MOVING INTO WRN ONTARIO ON WED WL BRING A MILDER AIR MASS INTO WI. 8H TEMPS CONT TO RISE TO ALMOST +6C BY 00Z THU AND WITH SKIES STILL MOSTLY SUNNY...TEMPS WL BE ABLE TO RISE CLOSE TO SEASONAL NORMS (MID 30S TO AROUND 40 DEGS). SOME INCREASE IN CLOUDS CAN BE EXPECTED WED NGT AS A WEAK CDFNT PUSHES TOWARD THE WRN GREAT LAKES. NO PCPN IS FCST INITIALLY DUE TO THE VERY DRY AIR MASS OVER WI AT THE ONSET. PERSISTENT SW WINDS COMBINED WITH THE INCREASE IN CLOUDS...WL PREVENT TEMPS FROM FALLING AS FAR AS THE PAST TWO NGTS. LOOK FOR READINGS TO ONLY SETTLE INTO THE MID TO UPR 20S. THIS APPROACHING CDFNT IS PROGGED TO SLOW ITS FORWARD SPEED...WAITING FOR A TRAILING SHORTWAVE TROF (OVER THE UPR MS VALLEY) TO CATCH UP ON THU. AS THIS OCCURS...THE ATMOSPHERE WL CONT TO GRADUALLY SATURATE...AS WELL AS SEEING INCREASED LIFT FROM THE RIGHT ENTRANCE REGION OF THE UPR JET. CANNOT RULE OUT SOME LIGHT PCPN DEVELOPING SOMEWHERE OVER THE FCST AREA...ESPECIALLY DURING THE AFTERNOON. TEMPS SHOULD BE ABLE TO WARM ENUF SUCH THAT MOST OF THE PCPN WOULD FALL AS RAIN...ALTHO A MIX IS POSSIBLE ESPECIALLY IF THE PCPN CAN REACH NRN WI. THE WEAK CDFNT/SHORTWAVE TROF COMBINATION TO THEN PUSH ACROSS MOST OF WI THU NGT AND BRING AT LEAST A CHC OF PCPN TO THE ENTIRE FCST AREA. FCST ISSUE WL BE ON PCPN TYPE AS TEMPS DROP INTO THE UPR 20S TO LWR 30S AND THE 8H 0C ISOTHERM HOVERS OVER NE WI. SINCE THE BULK OF PCPN APPEARS TO MOVE THRU NE WI THU EVENING...ANTICIPATE PCPN TO FALL AS LIGHT SNOW NORTH AND A RAIN/SNOW MIX OVER CNTRL AND E-CNTRL WI. THIS SYSTEM IS FCST TO CLEAR THE REGION BY FRI...ALTHO THE LACK OF DRY AIR AND SUBSIDENCE BEHIND THE SYSTEM MAY KEEP MORE CLOUDS AROUND THRU THE DAY. DUE TO THE WEAK NATURE OF THE CDFNT AND WINDS ALOFT ONLY VEERING TO THE WEST...MAX TEMPS ON FRI ARE STILL EXPECTED TO BE NEAR NORMAL FOR MID-NOVEMBER. LARGE MDL DIFFERENCES REMAIN NEXT WEEKEND AS THE GFS/GEM FAVOR MORE OF A NRN STREAM SYSTEM IMPACTING NE WI SAT NGT INTO SUNDAY. ON THE OTHER HAND...THE ECMWF CONTS TO FOCUS ON A STRONGER SRN STREAM SYSTEM LIFTING N-NE FROM THE SRN PLAINS TO THE GREAT LAKES FROM SAT NGT INTO SUNDAY. WHILE THE THERMAL PROFILES WOULD INDICATE RAIN AS THE PRIMARY PCPN TYPE NO MATTER WHICH SOLUTION VERIFIES...THE ECMWF SOLUTION WOULD TAP MORE GULF MOISTURE AND THEREBY BRINGS HEAVIER RAINS TO NE WI. UNTIL THESE DIFFERENCES CAN BE BETTER RESOLVED... WL KEEP POPS IN THE CHC CATEGORY FOR BOTH SAT NGT AND SUNDAY WITH TEMPS ACTUALLY ABOVE NORMAL THRU THE WEEKEND. && .AVIATION...FOR 12Z TAF ISSUANCE ISSUED AT 543 AM CST MON NOV 11 2013 A STRONG ARCTIC COLD FRONT MOVING THROUGH THE FORECAST AREA THIS MORNING WILL BRING GUSTY NW WINDS...FALLING TEMPS AND SOME LIGHT RAIN OR SNOW THIS MORNING. MVFR CONDITIONS WILL OCCUR WITH THE SNOW...LINGERING OVER THE REGION FOR A WHILE THIS MORNING. SCATTERED LAKE-EFFECT SNOW SHOWERS AND ASSOCIATED MVFR CONDITIONS WILL CONTINUE OVER NC WI THROUGH TONIGHT...WHILE THE REST OF THE REGION SEES CLEARING SKIES IN THE AFTERNOON. COLD AND BREEZY CONDITIONS EXPECTED THROUGH THE NIGHT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....TE LONG TERM......KALLAS AVIATION.......TE
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 428 AM CST MON NOV 11 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY INDICATE STRONG COLD FRONT NOW EXTENDING ACROSS CWA FROM NEAR IMT TO RRL. BEHIND THE FRONT TEMPERATURES DROPPING QUICKLY INTO LOWER TO MIDDLE 20S. NORTHWEST WINDS ALSO QUITE GUSTY BEHIND FRONT. RADAR RETURNS HAVE FILLED IN/EXPANDED MIDNIGHT ONWARD IN RESPONSE TO STRONG FGEN FORCING OVER NORTHERN AND CENTRAL WI. LIGHT SNOW FALLING NORTH OF FRONT...RAIN SOUTH. NO SNOWFALL AMOUNTS REPORTED AS OF YET...THOUGH WEBCAMS FAR NORTH LOOK LIKE GOOD INCH HAS FALLEN SO FAR. MAIN CHANGE IN THIS FORECAST WAS TO SLOW PROGRESSION SLIGHTLY...INCLUDING RAIN TO SNOW CHANGEOVER. FORCING EXPECTED TO DROP SOUTH AND EAST THROUGH AREA THROUGH MID MORNING. HAVE TRIED TO DEPICT TEMP DROP THROUGH THIS MORNING...THEN NEAR STEADY TEMPS THROUGH THE AFTERNOON. WITH SLOWER DROP IN TEMPS OVER FOX VALLEY THIS MORNING...WILL UPDATE SPS SENT OUT EARLIER TO HIGHLIGHT AREAS WEST AND NORTH FOR THE MORNING COMMUTE. HIGH PRESSURE TO DROP SOUTH INTO THE PLAINS TONIGHT AND TUE MAKING CONDITIONS LESS FAVORABLE FOR LES OVER THE NORTH. HAVE STAYED WITH CHANCE/SCATTERED WORDING AND PREVIOUS SNOW AMOUNTS IN THE SNOW BELT FOR TODAY GIVEN DRY AIR AND LOWERING INVERSION HEIGHTS. COLD TEMPS TO CONTINUE THROUGH THE PERIOD WITH APPARENT TEMPS TODAY RUNNING IN THE SINGLE DIGITS NORTH AND TEENS SOUTH. TONIGHT WINDS WILL MAKE IT FEEL LIKE NEAR ZERO NORTH AND SINGLE DIGITS SOUTH. LIGHTER WINDS LATER TUE WILL BRING SOME IMPROVEMENT. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 428 AM CST MON NOV 11 2013 MDLS CONT TO INDICATE THE DEVELOPMENT OF UPR RDGS OVER THE ERN PACIFIC AND WRN ATLANTIC WITH A BROAD UPR TROF OVER THE CNTRL CONUS. MEAN FLOW OVER THE GREAT LAKES WL SWITCH FROM NW TO SW AS THIS UPR TROF DEVELOPS WHICH WL BRING MILDER...BUT MORE UNSETTLED WEATHER TO NE WI TOWARD NEXT WEEKEND. MAIN FCST ISSUE WL BE TRYING TO DETERMINE BEST PERIOD TO MENTION PCPN CHCS AS THE MDLS DIFFER ON WHICH BRANCH OF THE JET WL BECOME MORE DOMINANT. THE SFC RDG AXIS TO EXTEND FROM THE SRN PLAINS NEWD TO SRN SECTIONS OF THE GREAT LAKES TUE NGT. MEANWHILE...A WEAKENING UPR RDG WL BE PUSHING ACROSS THE UPR MS VALLEY TOWARD WI. THIS TRANSLATES TO A QUIET WEATHER PATTERN FOR NE WI UNDER MOSTLY CLR SKIES AND W-SW WINDS UNDER 10 MPH. WEAK WAA TO PERSIST THRU THE NGT AND THIS WL HELP TO COUNTER THE UNSEASONABLY COOL AIR MASS OVERHEAD. MIN TEMPS ARE EXPECTED TO BE CLOSE TO VALUES SEEN MON NGT (GENERALLY TEENS INLAND...AROUND 20 NEAR LAKE MI). INCREASING SW WINDS BETWEEN THE SFC HI OVER THE TN VALLEY AND A SFC LOW MOVING INTO WRN ONTARIO ON WED WL BRING A MILDER AIR MASS INTO WI. 8H TEMPS CONT TO RISE TO ALMOST +6C BY 00Z THU AND WITH SKIES STILL MOSTLY SUNNY...TEMPS WL BE ABLE TO RISE CLOSE TO SEASONAL NORMS (MID 30S TO AROUND 40 DEGS). SOME INCREASE IN CLOUDS CAN BE EXPECTED WED NGT AS A WEAK CDFNT PUSHES TOWARD THE WRN GREAT LAKES. NO PCPN IS FCST INITIALLY DUE TO THE VERY DRY AIR MASS OVER WI AT THE ONSET. PERSISTENT SW WINDS COMBINED WITH THE INCREASE IN CLOUDS...WL PREVENT TEMPS FROM FALLING AS FAR AS THE PAST TWO NGTS. LOOK FOR READINGS TO ONLY SETTLE INTO THE MID TO UPR 20S. THIS APPROACHING CDFNT IS PROGGED TO SLOW ITS FORWARD SPEED...WAITING FOR A TRAILING SHORTWAVE TROF (OVER THE UPR MS VALLEY) TO CATCH UP ON THU. AS THIS OCCURS...THE ATMOSPHERE WL CONT TO GRADUALLY SATURATE...AS WELL AS SEEING INCREASED LIFT FROM THE RIGHT ENTRANCE REGION OF THE UPR JET. CANNOT RULE OUT SOME LIGHT PCPN DEVELOPING SOMEWHERE OVER THE FCST AREA...ESPECIALLY DURING THE AFTERNOON. TEMPS SHOULD BE ABLE TO WARM ENUF SUCH THAT MOST OF THE PCPN WOULD FALL AS RAIN...ALTHO A MIX IS POSSIBLE ESPECIALLY IF THE PCPN CAN REACH NRN WI. THE WEAK CDFNT/SHORTWAVE TROF COMBINATION TO THEN PUSH ACROSS MOST OF WI THU NGT AND BRING AT LEAST A CHC OF PCPN TO THE ENTIRE FCST AREA. FCST ISSUE WL BE ON PCPN TYPE AS TEMPS DROP INTO THE UPR 20S TO LWR 30S AND THE 8H 0C ISOTHERM HOVERS OVER NE WI. SINCE THE BULK OF PCPN APPEARS TO MOVE THRU NE WI THU EVENING...ANTICIPATE PCPN TO FALL AS LIGHT SNOW NORTH AND A RAIN/SNOW MIX OVER CNTRL AND E-CNTRL WI. THIS SYSTEM IS FCST TO CLEAR THE REGION BY FRI...ALTHO THE LACK OF DRY AIR AND SUBSIDENCE BEHIND THE SYSTEM MAY KEEP MORE CLOUDS AROUND THRU THE DAY. DUE TO THE WEAK NATURE OF THE CDFNT AND WINDS ALOFT ONLY VEERING TO THE WEST...MAX TEMPS ON FRI ARE STILL EXPECTED TO BE NEAR NORMAL FOR MID-NOVEMBER. LARGE MDL DIFFERENCES REMAIN NEXT WEEKEND AS THE GFS/GEM FAVOR MORE OF A NRN STREAM SYSTEM IMPACTING NE WI SAT NGT INTO SUNDAY. ON THE OTHER HAND...THE ECMWF CONTS TO FOCUS ON A STRONGER SRN STREAM SYSTEM LIFTING N-NE FROM THE SRN PLAINS TO THE GREAT LAKES FROM SAT NGT INTO SUNDAY. WHILE THE THERMAL PROFILES WOULD INDICATE RAIN AS THE PRIMARY PCPN TYPE NO MATTER WHICH SOLUTION VERIFIES...THE ECMWF SOLUTION WOULD TAP MORE GULF MOISTURE AND THEREBY BRINGS HEAVIER RAINS TO NE WI. UNTIL THESE DIFFERENCES CAN BE BETTER RESOLVED... WL KEEP POPS IN THE CHC CATEGORY FOR BOTH SAT NGT AND SUNDAY WITH TEMPS ACTUALLY ABOVE NORMAL THRU THE WEEKEND. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1119 PM CST SUN NOV 10 2013 A STRONG ARCTIC COLD FRONT WILL MOVE THROUGH THE FORECAST AREA OVERNIGHT INTO EARLY MONDAY...BRINGING GUSTY NW WINDS...FALLING TEMPS AND SOME LIGHT SNOW. RAIN WILL BE POSSIBLE EARLY IN THE TAF PERIOD AT ATW/GRB. THE SNOW WILL BE HEAVIEST WHEN THE FRONT MOVES THROUGH...WITH VSBYS DROPPING TO AS LOW AS 1SM-2SM. MVFR/IFR CONDITIONS WILL OCCUR WITH THE SNOW...AND SOME MVFR CIGS WILL LINGER OVER THE REGION FOR A WHILE MONDAY MORNING. LAKE-EFFECT SNOW SHOWERS AND ASSOCIATED MVFR CONDITIONS SHOULD CONTINUE OVER NC WI THROUGH THE DAY...WHILE THE REST OF THE REGION SEES AN IMPROVEMENT TO VFR CONDITIONS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....TE LONG TERM......KALLAS AVIATION.......KIECKBUSCH Area Forecast Discussion National Weather Service Lincoln IL 503 PM CST Mon Nov 11 2013 .DISCUSSION... ISSUED 300 PM CST Mon Nov 11 2013...correction Much colder air will arrive tonight and modify only slightly through Wednesday morning. A warming trend still looks likely later this week as the mid week upper ridge shifts east of IL and a southwest flow develops aloft. The warming will become more noticeable next weekend as highs return to the 50s on Saturday and around 60 on Sunday. Rainy conditions are forecast for at least the last half of next weekend, as a long wave trough digs into the Plains. The timing of that system is still uncertain, but another cold push of air is projected behind that upper trough for either Monday (GFS) or Tuesday (ECMWF). SHORT TERM...Tonight through Thursday. The strong cold front will quickly depart to the southeast by evening, with post-frontal rain quickly changing to snow. Most upstream reports have indicated the snow melted as it fell, but slippery conditions developed as air temps plummeted below freezing. Some accidents have been reported due to icy spots on roads. The band of snow seems to be expanding in depth between 19z-20z, and that could keep snow flying for up to 4 hours or so once it develops. However, measurable snow is not really expected for more than a few minutes unless a snow burst overcomes the warm ground for a while. Visibilities have dipped to 1/4 mile in snow at times upstream in Iowa/Wisconsin, mainly due to windy conditions during the snowfall and not due to the heavy nature of the snowfall. The main axis of precipitation seems well correlated to the 850mb frontogenesis. Radar images show a more pronounced band of precipitation correlating to the change-over to snow, just passing over DVN at 20z. LAPS soundings show the change-over also correlating to a 925mb temp of -2C. Timing those conditions and that band into our area would put the change to snow in GBG around 330 pm, PIA at 430 pm, BMI by 515 pm, Lincoln at 6 pm, CMI/SPI at 630 pm, Effingham around 9 pm, and Lawrenceville around 1015 pm. Depending on the progression of 850mb Fgen, snow will generally last from 2 to 4 hours after those times. Areas southwest of a line from Rushville to Effingham will see weaker forcing, based on the latest RAP output, which should limit precip amounts in those areas. Subsidence and dry air should help to shut down the preciptation in our southeastern areas between 2-3 am. Skies should begin to clear about 4 to 5 hours after the precipitation ends, based on satellite trends and forecast RH in the low to mid levels. Lows will have a chance to drop into the upper teens W of I-55, with low to mid 20s elsewhere. Dry and unseasonably cold air will limit highs on Tuesday to the low 30s near GBG and upper 30s near LWV. Clear skies and light winds under the surface ridge axis on Tuesday night should allow all areas to drop into the teens for lows. Some warming in the 850mb layer should help to temper lows from dropping into the 10-15 deg range. A couple of traditional cold spots may end up that cold. Wednesday will see the surface ridge slide east of IL and rising heights aloft aiding in warming through a deep column. The air temps near the ground will be slow to rebound, but a steady rise by 5 degrees for highs is expected Wed and Thursday. LONG TERM...Thursday night through Monday. Northern and southern stream jet interactions will aid in carving a trough in the Rockies and western Plains on Thursday. Increasing southwest flow in the lee of the trough will push moisture and clouds into Illinois Thursday night. We could see enough rising motion from warm advection to generate a few rain showers west of I-55. Chance PoPs were only included west of Rushville to Lacon in the NW. The rain may change to snow north of Peoria late Thur night, but precip amounts will be light and no accumulation is expected. A 500mb shortwave and the corresponding surface trough will pass across IL on Friday, with additional rain showers possible. We only used slight chance PoPs for Friday as the system will be weakening as it pushes into a ridge over the eastern states. The upper trough across the western half of the lower 48 is expected to amplify next weekend, increasing the moisture return into IL. A low level jet is expected to intensify by Sunday morning and nose into IL, triggering more widespread showers starting as early as Saturday night. Showers may linger through Monday per the GFS, or through Tues if the slower ECMWF verifies. && .AVIATION... ISSUED 441 PM CST Mon Nov 11 2013 Transition zone between precip phases has moved south of KPIA and should be south of KBMI by TAF valid time and the rest of the terminals soon after. Vsbys ahead of the snow are generally MVFR with occasional IFR. Once the precip transitions to snow, vsbys generally fall to IFR. There may be a brief period of vsbys blo 1 nm during the periods of more substantial snow. CIGs are IFR at all terminals and should remain so until precip ends in the 02-04z time frame. The main axis of the shortwave should move across Illinois later tonight and fairly rapid clearing should be likely following its passage. Winds will be gusty out of the north through much of the night as striong 1040mb+ high moves quickly into the middle Missouri Valley. As the high center pushes into Kansas and Missouri Tuesday afternoon, winds should drop off and begin to gain a westerly component. Barker && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
413 PM CST MON NOV 11 2013 .DISCUSSION... 259 PM CST SEVERAL NEAR TERM FORECAST CONCERNS AND CHALLENGES WITH PRECIPITATION ENDING FROM NORTH TO SOUTH INTO THE EVENING...WITH LAKE EFFECT SNOW DEVELOPING THROUGH THE EVENING IMPACTING PORTIONS OF NORTHWEST INDIANA TO SOME DEGREE THROUGH THE OVERNIGHT. AFTERNOON WATER VAPOR IMAGERY SHOWS A DEEP UPPER LOW SPINNING OVER SOUTHERN JAMES BAY AS PART OF A BROAD UPPER TROUGH SPREADING ACROSS THE EASTERN HALF OF THE COUNTRY. RIDGING IS BUILDING OVER THE PACIFIC NORTHWEST AND BRITISH COLUMBIA AS ANOTHER UPPER LOW SPINS OVER THE WEST COAST WITH YET ANOTHER TROUGH JUST TO ITS WEST. AT THE SURFACE...LOW PRESSURE ASSOCIATED WITH THE JAMES BAY UPPER LOW IS MOVING INTO NORTHERN QUEBEC WITH A COLD FRONT TRAILING IT TO THE SOUTHWEST AND HAVING EXITED THE SOUTHERN CWA. STRONG HIGH PRESSURE IS SETTLING SOUTHWARD INTO THE PLAINS AND WESTERN GREAT LAKES. THIS EVENING...CURRENT POST FRONTAL BAND OF PRECIPITATION CONTINUES TO GRADUALLY WORK SOUTHWARD ACROSS THE CENTRAL AND SOUTHERN CWA. THIS BAND WILL CONTINUE SOUTHWARD THROUGH EARLY EVENING BEFORE ENDING ACROSS THE SOUTHERN CWA BY MID EVENING OR SO. FAIRLY INTENSE SNOWFALL PRODUCING VISIBILITY UNDER A MILE AT TIMES WILL CONTINUE AS THE COLDER AIR SPREAD SOUTH...WITH AREAS THAT ARE CURRENTLY RAIN CHANGING OVER. HAVE HAD REPORTS OF AROUND A HALF INCH OF ACCUMULATION ON GRASSY AND OTHER NON PAVED SURFACES AND EXPECT THAT THIS WILL CONTINUE TO BE THE TREND UNTIL THE SNOW WINDS DOWN. THE MAIN CONCERN WITH THIS WILL BE TEMPS FALLING BELOW FREEZING ACROSS AREAS THAT HAVE NOT ALREADY DONE SO THROUGH SUNSET. PRECIP MAY END BEFORE THIS OCCURS IN SOME AREAS BUT THIS WILL SET UP POTENTIAL FOR RESIDUAL MOISTURE ON VARIOUS SURFACES TO FREEZE BEFORE DRYING SO MOTORISTS AND PEDESTRIANS SHOULD BE ALERT. TONIGHT AND TUESDAY...THE FOCUS WILL BE ON LAKE EFFECT SNOW PLACEMENT TONIGHT THROUGH TUESDAY MORNING. THE UPPER LOW WILL CONTINUE EASTWARD TO THE GULF OF ST. LAWRENCE BY TUESDAY MORNING WITH AN ASSOCIATED TROUGH AXIS CROSSING THE LOCAL AREA. NORTHERLY LOW AND MID LEVEL FLOW WILL BE IN PLACE ACROSS LAKE MICHIGAN THIS EVENING AND OVERNIGHT WITH CONTINUED COLD ADVECTION BRINGING H85 TEMPS DOWN TO AROUND -12 C CREATING LAKE TO H85 DELTA-TS OF 20+C. GENERATING LAKE EFFECT WILL NOT BE A PROBLEM...ITS THE PLACEMENT THAT IS THE MAIN CHALLENGE. MEAN LOW LEVEL FLOW THIS EVENING WILL START OUT NORTHWESTERLY ACROSS NORTHERN PORTIONS OF THE LAKE AND NORTHERLY SOUTH AS THE COLDER AIR CONTINUES TO ADVECT IN. WITH TIME...THE MEAN FLOW WILL GAIN MORE OF A WEST COMPONENT/THOUGH STILL REMAINING NORTHWESTERLY OVERALL/ INTO TUESDAY MORNING. THE INITIAL CONVERGENCE LOOKS TO SET UP ACROSS NORTHERN SECTIONS OF THE LAKE CLOSER TO THE MICHIGAN SHORE BASED ON THE NORTHWEST DIRECTION AND FAIRLY STRONG SPEEDS FOCUSING FRICTIONAL CONVERGENCE CLOSER TO SHORE. THE BAND MAY ARC SOUTH OR SOUTHWEST AS IT DEVELOPS SOUTHWARD AS THE FLOW TURNS MORE NORTHERLY...BUT MAY STILL REMAIN FAIRLY CLOSE TO THE MICHIGAN SHORELINE. AM CONCERNED BY THE NEARLY DUE NORTH DIRECTION THIS EVENING BUT DEVELOPMENT OF MORE ORGANIZED BANDS MAY HOLD OFF UNTIL CLOSER TO MIDNIGHT. THIS MAY RESULT IN PORTER COUNTY AND EVEN PORTIONS OF JASPER COUNTY SEEING A PERIOD OF DECENT SNOWFALL LATER THIS EVENING AND EARLY TONIGHT BEFORE WINDS TURN SLIGHTLY NORTHWEST PUSHING THE BAND FURTHER EAST TOWARD DAYBREAK. MOST OF THE HIGH RES GUIDANCE HAS BEEN BULLISH ON KEEPING THE BAND CLOSER TO THE MICHIGAN SHORE AND INTO LAPORTE AND BERRIEN COUNTIES AND EVEN POINTS FURTHER EAST...WITH MUCH LESS ACTIVITY IN PORTER/JASPER. AM WONDERING IF THEY ARE A LITTLE TOO BULLISH ON HOW FAR EAST THE FOCUS BECOMES. WITH A STRONG NORTH COMPONENT HAVE A HARD TIME SEEING THE BAND DEVELOPING ALL THE WAY ON THE EAST SIDE OF THE LAKE AND MORE OR LESS STAYING THERE UNLESS TIMING OF ACTUAL PLUME DEVELOPMENT IS DELAYED UNTIL WINDS START TO TURN MORE NORTHWEST. INTERESTINGLY...SOME OF THE LATEST RAP GUIDANCE FALLS MORE IN LINE WITH THIS THOUGHT PROCESS. WHILE THERE IS SIGNIFICANT BUST POTENTIAL HERE...WILL GO AHEAD AND ISSUE A LAKE EFFECT SNOW ADVISORY FOR PORTER AND JASPER HIGHLIGHTING THE LATE EVENING AND OVERNIGHT HOURS AS THE PERIOD OF BEST HEAVY SNOW POTENTIAL ACROSS MAINLY THE EAST HALF OF EACH COUNTY. SNOWFALL RATES MAY BE QUITE INTENSE ON THE ORDER OF SEVERAL INCHES PER HOUR BUT THE DURATION IS STILL A QUESTION MARK. COMBINE THIS WITH GUSTY WINDS FAIRLY ROUGH CONDITIONS MAY DEVELOP ASSUMING THE BAND AFFECTS THESE AREAS. STILL CANNOT RULE OUT WARNING LEVEL SNOWS OVER 6 INCHES BUT WITH A FAIR AMOUNT OF SUPPORT FOR LESSER AMOUNTS HAVE A HARD TIME GOING WITH A WARNING AT THIS POINT. FOLLOWING THE IDEA THAT THE BAND WILL INITIALLY IMPACT PORTER/JASPER THEN SHIFT EASTWARD FEEL A BIT MORE COMFORTABLE GOING WITH AN ADVISORY THAN JUST KEEPING THE WATCH. THE EVENING SHIFT WILL NEED TO MONITOR CLOSELY. BEYOND THAT...LOWS WILL FALL INTO THE LOW TO MID 20S TONIGHT WITH READINGS CLOSER TO 30 NEAR AND DOWNWIND OF THE LAKE. DRY CONDITIONS WILL PERSIST ACROSS THE MAJORITY OF THE AREA WITH LAKE EFFECT SHOWERS ENDING EAST TUESDAY. HIGHS WILL ONLY MAKE IT INTO LOW TO MID 30S. WEDNESDAY AND BEYOND...DID NOT HAVE A WHOLE LOT OF TIME TO LOOK FURTHER AHEAD IN THE FORECAST PERIOD BUT HIGH PRESSURE WILL BE SETTLING INTO THE LOWER OHIO VALLEY WEDNESDAY AS THE WESTERN UPPER RIDGE IS SHUNTED EASTWARD. THIS WILL ALLOW MODEST WARM ADVECTION TO DEVELOP IN THE MID LEVELS WITH A STEADY SOUTHWEST WIND AT THE SURFACE AS THE HIGH SHIFTS EASTWARD. MAY BE A LITTLE TOO CONSERVATIVE WITH UPPER 30S HIGHS WITH ANY SNOWPACK IN NW INDIANA LIKELY KEEPING THINGS IN THE 30S REGARDLESS. THE UPPER RIDGE WILL BE BROKEN DOWN AS IT TRANSLATES EASTWARD AS A FAIRLY BROAD LONGWAVE TROUGH MOVES ACROSS THE ROCKIES AND INTO THE PLAINS THURSDAY. A WEAK SURFACE TROUGH IS EXPECTED TO ACCOMPANY THIS AND BRING A WEAK COOL FRONT ACROSS THE AREA THURSDAY NIGHT OR FRIDAY WITH A LOW CHANCE FOR RAIN/SNOW AT NIGHT AND SHOWERS DURING THE DAY. LOW AMPLITUDE FLOW WILL THEN MOVE ACROSS THE AREA SATURDAY WITH AN AMPLIFYING TROUGH SPREADING IN LATER IN THE WEEKEND AND EARLY NEXT WEEK. A SURFACE LOW IS FORECAST TO DEEPEN AS THE TROUGH AMPLIFIES BUT ECMWF/GFS ARE AT ODDS ON HOW QUICKLY THIS OCCURS. A WARMUP SHOULD OCCUR IN THE SOUTHERLY FLOW AHEAD OF THE LOW BUT THIS MAY BE BRIEF IF A FASTER SOLUTION PANS OUT. EITHER WAY MOIST SOUTHERLY FLOW POINTS TOWARD INCREASING PRECIP CHANCES SUNDAY WHICH MAY CONTINUE THROUGH MONDAY IF THE SLOWER SOLUTION PANS OUT. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * SNOW ENDING AROUND 23Z AT ORD...00Z AT MDW. * IFR CIGS QUICKLY LIFTING THROUGH MVFR AFTER SNOW ENDS...WITH VFR CIGS BY 2330Z AT ORD...0030Z AT MDW. * STRONG/GUSTY NORTH/NORTHEAST WINDS SLOWLY TURNING BACK NORTH/ NORTHWEST BETWEEN 23Z-01Z. * GUSTY NORTH/NORTHWEST WINDS THROUGH THE PERIOD. CMS //DISCUSSION...UPDATED 22Z... BACK EDGE OF THE SNOW IS STEADILY MOVING SOUTH ACROSS NORTHERN IL WITH RAPID IMPROVEMENT AFTER THE SNOW ENDS. A LAKE ENHANCED BOUNDARY MOVED THROUGH THE TERMINALS A FEW HOURS AGO SHIFTING WINDS NORTH/NORTHEAST. WINDS STILL FROM 010 ON THE ONE MINUTE DATA AT ORD/MDW. EXPECT WIND DIRECTIONS TO SLOWLY SHIFT BACK TO NORTH/ NORTHWEST AFTER THE SNOW ENDS. SOME POTENTIAL FOR WINDS TO REMAIN GUSTY INTO THIS EVENING...BUT OBSERVATIONS ACROSS FAR NORTHERN IL AND SOUTHERN WI SHOW GUSTS DIMINISHING...THUS GUSTS COULD BECOME LESS PREVAILING INTO EARLY THIS EVENING. CMS PREVIOUS 18Z DISCUSSION... DETERIORATING CONDITIONS ONGOING ACROSS THE TERMINALS EARLY THIS AFTERNOON...ESPECIALLY NEAR RFD WHERE THE RAIN/SNOW MIX QUICKLY TRANSITIONED OVER TO ALL SNOW. THIS TREND WILL CONTINUE WITH THE REMAINING TERMINALS OVER THE NEXT 1-2 HOURS...AND GYY BY THE 21Z TIME FRAME. VISIBILITY OF 3-5 MILES IN THIS RAIN/SNOW MIX WILL LIKELY BE OBSERVED BUT WITH VISIBILITY EXPECTED TO FALL TO 1-2 MILES IN THE SNOW. BRIEF BURSTS OF HEAVIER SNOW CANT BE RULED OUT THIS AFTERNOON...BUT ONCE AGAIN PREVAILING VIS STAYING AROUND 1-2 MILES. THIS SNOW SHOULD TAPER OFF BY AROUND 23Z...BUT LINGER OVER THE GYY TERMINAL INTO THE EVENING AS LAKE EFFECT SNOW SHOWERS COULD COME RATHER CLOSE TO THE TERMINAL. ANY HEAVIER LAKE EFFECT SNOW SHOWERS SHOULD REMAIN TO THE EAST OF GYY...BUT WILL NEED TO CONTINUE TO MONITOR THE POSSIBILITY FOR A BRIEF/STRAY SNOW SHOWER TO INCH CLOSE TO THE TERMINAL. CEILINGS HAVE BEEN RAPIDLY DROPPING AT THIS HOUR AS WELL...WITH MVFR CEILINGS IN PLACE. DO EXPECT A CONTINUED DOWNWARD TREND IN CEILINGS WILL IFR CEILINGS LIKELY LATER THIS AFTERNOON. WITH THE DEPARTING PRECIP LATE THIS AFTERNOON...EXPECT CEILINGS TO SLOWLY IMPROVE BUT THEN IMPROVE SIGNIFICANTLY BY EARLY EVENING. NORTH NORTHWEST WINDS HAVE BEEN SLOW TO INCREASE TODAY...BUT WITH INCREASED SPEEDS/GUSTS STILL EXPECTED INTO THE AFTERNOON AND EARLY EVENING. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 22Z... * HIGH FOR SNOW/VIS/CIG AND IMPROVEMENT TRENDS LATE THIS AFTERNOON AND EARLY THIS EVENING. * MEDIUM FOR WIND SPEEDS/DIRECTIONS/GUSTS THROUGH THE PERIOD. CMS //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...MAINLY VFR. JUST EAST OF TERMINALS MVFR CIGS AND PSBL LAKE EFFECT CLOUDS. WEDNESDAY THROUGH THURSDAY...VFR. FRIDAY...MVFR POSSIBLE WITH CHC OF LIGHT RAIN/SNOW BEFORE DAYBREAK. THEN CHC OF LIGHT RAIN AFT DAYBREAK. SATURDAY...CHC OF RAIN AND MVFR CIGS. SUNDAY...PSBL MVFR CIGS WITH CHC OF RAIN. BEACHLER && .MARINE... 338 PM CST A COLD FRONT PUSHED DOWN THE LENGTH OF LAKE MI DURING LATE OVERNIGHT AND THIS MORNING WITH WINDS SHIFTING TO OUT OF THE NW AND N WITH 35 KT GALES. WINDS HAD FALLEN TO A BIT BELOW GALE FORCE ON THE N AND CENTRAL PORTIONS OF THE LAKE AT MID AFTERNOON...AND ARE EXPECTED TO DO SO ON THE S PORTION LATE THIS AFTERNOON. HOWEVER...A SECOND SURGE OF COLD AIR MOVING ACROSS NORTHERN WI AND THE U.P. OF MI WILL QUICKLY MOVE S DOWN THE LAKE LATE THIS AFTERNOON AND EARLY THIS EVENING WITH WINDS EXPECTED TO INCREASE BACK TO 35 KT GALES BEFORE GRADUALLY DIMINISHING OVERNIGHT AND CONTINUING TO DO SO DURING TUESDAY. WINDS BACK TO W TUE NIGHT AND SW WED...INCREASING TO 35-40 KT GALES AS A LARGE HIGH MOVES EAST-SOUTHEAST FROM THE CENTRAL PLAINS ACROSS THE MID MISSISSIPPI VALLEY AND REACHING THE SOUTHERN APPALACHIANS BY THU. SW GALES WILL CONTINUE THROUGH WED NIGHT INTO THU MORNING AS LOW PRESSURE THAT DEVELOPED OVER ALBERTA TUE DEEPENS AS IT MOVES QUICKLY E TO JAMES BAY BY THU MORNING. WINDS AND WAVES MEETING OR EXCEEDING OF SMALL CRAFT ADVISORY CRITERIA WILL ALONG THE IL SHORE UNTIL LATE TUE EVENING...AND INTO OVERNIGHT TUE. WINDS WILL LIKELY INCREASE BACK TO ABOVE SMALL CRAFT CRITERIA BY WED AFTERNOON. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...LAKE EFFECT SNOW ADVISORY...INZ002-INZ011...9 PM MONDAY TO NOON TUESDAY. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ744-LMZ745-LMZ777- LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM TUESDAY. SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM TUESDAY. SMALL CRAFT ADVISORY...LMZ744-LMZ745...3 AM TUESDAY TO 3 AM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
400 PM CST MON NOV 11 2013 .DISCUSSION... 259 PM CST SEVERAL NEAR TERM FORECAST CONCERNS AND CHALLENGES WITH PRECIPITATION ENDING FROM NORTH TO SOUTH INTO THE EVENING...WITH LAKE EFFECT SNOW DEVELOPING THROUGH THE EVENING IMPACTING PORTIONS OF NORTHWEST INDIANA TO SOME DEGREE THROUGH THE OVERNIGHT. AFTERNOON WATER VAPOR IMAGERY SHOWS A DEEP UPPER LOW SPINNING OVER SOUTHERN JAMES BAY AS PART OF A BROAD UPPER TROUGH SPREADING ACROSS THE EASTERN HALF OF THE COUNTRY. RIDGING IS BUILDING OVER THE PACIFIC NORTHWEST AND BRITISH COLUMBIA AS ANOTHER UPPER LOW SPINS OVER THE WEST COAST WITH YET ANOTHER TROUGH JUST TO ITS WEST. AT THE SURFACE...LOW PRESSURE ASSOCIATED WITH THE JAMES BAY UPPER LOW IS MOVING INTO NORTHERN QUEBEC WITH A COLD FRONT TRAILING IT TO THE SOUTHWEST AND HAVING EXITED THE SOUTHERN CWA. STRONG HIGH PRESSURE IS SETTLING SOUTHWARD INTO THE PLAINS AND WESTERN GREAT LAKES. THIS EVENING...CURRENT POST FRONTAL BAND OF PRECIPITATION CONTINUES TO GRADUALLY WORK SOUTHWARD ACROSS THE CENTRAL AND SOUTHERN CWA. THIS BAND WILL CONTINUE SOUTHWARD THROUGH EARLY EVENING BEFORE ENDING ACROSS THE SOUTHERN CWA BY MID EVENING OR SO. FAIRLY INTENSE SNOWFALL PRODUCING VISIBILITY UNDER A MILE AT TIMES WILL CONTINUE AS THE COLDER AIR SPREAD SOUTH...WITH AREAS THAT ARE CURRENTLY RAIN CHANGING OVER. HAVE HAD REPORTS OF AROUND A HALF INCH OF ACCUMULATION ON GRASSY AND OTHER NON PAVED SURFACES AND EXPECT THAT THIS WILL CONTINUE TO BE THE TREND UNTIL THE SNOW WINDS DOWN. THE MAIN CONCERN WITH THIS WILL BE TEMPS FALLING BELOW FREEZING ACROSS AREAS THAT HAVE NOT ALREADY DONE SO THROUGH SUNSET. PRECIP MAY END BEFORE THIS OCCURS IN SOME AREAS BUT THIS WILL SET UP POTENTIAL FOR RESIDUAL MOISTURE ON VARIOUS SURFACES TO FREEZE BEFORE DRYING SO MOTORISTS AND PEDESTRIANS SHOULD BE ALERT. TONIGHT AND TUESDAY...THE FOCUS WILL BE ON LAKE EFFECT SNOW PLACEMENT TONIGHT THROUGH TUESDAY MORNING. THE UPPER LOW WILL CONTINUE EASTWARD TO THE GULF OF ST. LAWRENCE BY TUESDAY MORNING WITH AN ASSOCIATED TROUGH AXIS CROSSING THE LOCAL AREA. NORTHERLY LOW AND MID LEVEL FLOW WILL BE IN PLACE ACROSS LAKE MICHIGAN THIS EVENING AND OVERNIGHT WITH CONTINUED COLD ADVECTION BRINGING H85 TEMPS DOWN TO AROUND -12 C CREATING LAKE TO H85 DELTA-TS OF 20+C. GENERATING LAKE EFFECT WILL NOT BE A PROBLEM...ITS THE PLACEMENT THAT IS THE MAIN CHALLENGE. MEAN LOW LEVEL FLOW THIS EVENING WILL START OUT NORTHWESTERLY ACROSS NORTHERN PORTIONS OF THE LAKE AND NORTHERLY SOUTH AS THE COLDER AIR CONTINUES TO ADVECT IN. WITH TIME...THE MEAN FLOW WILL GAIN MORE OF A WEST COMPONENT/THOUGH STILL REMAINING NORTHWESTERLY OVERALL/ INTO TUESDAY MORNING. THE INITIAL CONVERGENCE LOOKS TO SET UP ACROSS NORTHERN SECTIONS OF THE LAKE CLOSER TO THE MICHIGAN SHORE BASED ON THE NORTHWEST DIRECTION AND FAIRLY STRONG SPEEDS FOCUSING FRICTIONAL CONVERGENCE CLOSER TO SHORE. THE BAND MAY ARC SOUTH OR SOUTHWEST AS IT DEVELOPS SOUTHWARD AS THE FLOW TURNS MORE NORTHERLY...BUT MAY STILL REMAIN FAIRLY CLOSE TO THE MICHIGAN SHORELINE. AM CONCERNED BY THE NEARLY DUE NORTH DIRECTION THIS EVENING BUT DEVELOPMENT OF MORE ORGANIZED BANDS MAY HOLD OFF UNTIL CLOSER TO MIDNIGHT. THIS MAY RESULT IN PORTER COUNTY AND EVEN PORTIONS OF JASPER COUNTY SEEING A PERIOD OF DECENT SNOWFALL LATER THIS EVENING AND EARLY TONIGHT BEFORE WINDS TURN SLIGHTLY NORTHWEST PUSHING THE BAND FURTHER EAST TOWARD DAYBREAK. MOST OF THE HIGH RES GUIDANCE HAS BEEN BULLISH ON KEEPING THE BAND CLOSER TO THE MICHIGAN SHORE AND INTO LAPORTE AND BERRIEN COUNTIES AND EVEN POINTS FURTHER EAST...WITH MUCH LESS ACTIVITY IN PORTER/JASPER. AM WONDERING IF THEY ARE A LITTLE TOO BULLISH ON HOW FAR EAST THE FOCUS BECOMES. WITH A STRONG NORTH COMPONENT HAVE A HARD TIME SEEING THE BAND DEVELOPING ALL THE WAY ON THE EAST SIDE OF THE LAKE AND MORE OR LESS STAYING THERE UNLESS TIMING OF ACTUAL PLUME DEVELOPMENT IS DELAYED UNTIL WINDS START TO TURN MORE NORTHWEST. INTERESTINGLY...SOME OF THE LATEST RAP GUIDANCE FALLS MORE IN LINE WITH THIS THOUGHT PROCESS. WHILE THERE IS SIGNIFICANT BUST POTENTIAL HERE...WILL GO AHEAD AND ISSUE A LAKE EFFECT SNOW ADVISORY FOR PORTER AND JASPER HIGHLIGHTING THE LATE EVENING AND OVERNIGHT HOURS AS THE PERIOD OF BEST HEAVY SNOW POTENTIAL ACROSS MAINLY THE EAST HALF OF EACH COUNTY. SNOWFALL RATES MAY BE QUITE INTENSE ON THE ORDER OF SEVERAL INCHES PER HOUR BUT THE DURATION IS STILL A QUESTION MARK. COMBINE THIS WITH GUSTY WINDS FAIRLY ROUGH CONDITIONS MAY DEVELOP ASSUMING THE BAND AFFECTS THESE AREAS. STILL CANNOT RULE OUT WARNING LEVEL SNOWS OVER 6 INCHES BUT WITH A FAIR AMOUNT OF SUPPORT FOR LESSER AMOUNTS HAVE A HARD TIME GOING WITH A WARNING AT THIS POINT. FOLLOWING THE IDEA THAT THE BAND WILL INITIALLY IMPACT PORTER/JASPER THEN SHIFT EASTWARD FEEL A BIT MORE COMFORTABLE GOING WITH AN ADVISORY THAN JUST KEEPING THE WATCH. THE EVENING SHIFT WILL NEED TO MONITOR CLOSELY. BEYOND THAT...LOWS WILL FALL INTO THE LOW TO MID 20S TONIGHT WITH READINGS CLOSER TO 30 NEAR AND DOWNWIND OF THE LAKE. DRY CONDITIONS WILL PERSIST ACROSS THE MAJORITY OF THE AREA WITH LAKE EFFECT SHOWERS ENDING EAST TUESDAY. HIGHS WILL ONLY MAKE IT INTO LOW TO MID 30S. WEDNESDAY AND BEYOND...DID NOT HAVE A WHOLE LOT OF TIME TO LOOK FURTHER AHEAD IN THE FORECAST PERIOD BUT HIGH PRESSURE WILL BE SETTLING INTO THE LOWER OHIO VALLEY WEDNESDAY AS THE WESTERN UPPER RIDGE IS SHUNTED EASTWARD. THIS WILL ALLOW MODEST WARM ADVECTION TO DEVELOP IN THE MID LEVELS WITH A STEADY SOUTHWEST WIND AT THE SURFACE AS THE HIGH SHIFTS EASTWARD. MAY BE A LITTLE TOO CONSERVATIVE WITH UPPER 30S HIGHS WITH ANY SNOWPACK IN NW INDIANA LIKELY KEEPING THINGS IN THE 30S REGARDLESS. THE UPPER RIDGE WILL BE BROKEN DOWN AS IT TRANSLATES EASTWARD AS A FAIRLY BROAD LONGWAVE TROUGH MOVES ACROSS THE ROCKIES AND INTO THE PLAINS THURSDAY. A WEAK SURFACE TROUGH IS EXPECTED TO ACCOMPANY THIS AND BRING A WEAK COOL FRONT ACROSS THE AREA THURSDAY NIGHT OR FRIDAY WITH A LOW CHANCE FOR RAIN/SNOW AT NIGHT AND SHOWERS DURING THE DAY. LOW AMPLITUDE FLOW WILL THEN MOVE ACROSS THE AREA SATURDAY WITH AN AMPLIFYING TROUGH SPREADING IN LATER IN THE WEEKEND AND EARLY NEXT WEEK. A SURFACE LOW IS FORECAST TO DEEPEN AS THE TROUGH AMPLIFIES BUT ECMWF/GFS ARE AT ODDS ON HOW QUICKLY THIS OCCURS. A WARMUP SHOULD OCCUR IN THE SOUTHERLY FLOW AHEAD OF THE LOW BUT THIS MAY BE BRIEF IF A FASTER SOLUTION PANS OUT. EITHER WAY MOIST SOUTHERLY FLOW POINTS TOWARD INCREASING PRECIP CHANCES SUNDAY WHICH MAY CONTINUE THROUGH MONDAY IF THE SLOWER SOLUTION PANS OUT. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * RAIN/SNOW MIX QUICKLY TRANSITIONING OVER TO ALL SNOW OVER THE NEXT HOUR...WITH VISIBILITY DROPPING TO AROUND 1 MILE AT TIMES. * IFR CEILINGS THIS AFTERNOON. * NNW WINDS INCREASING WITH GUSTS AROUND 20KT. RODRIGUEZ //DISCUSSION...UPDATED 18Z... DETERIORATING CONDITIONS ONGOING ACROSS THE TERMINALS EARLY THIS AFTERNOON...ESPECIALLY NEAR RFD WHERE THE RAIN/SNOW MIX QUICKLY TRANSITIONED OVER TO ALL SNOW. THIS TREND WILL CONTINUE WITH THE REMAINING TERMINALS OVER THE NEXT 1-2 HOURS...AND GYY BY THE 21Z TIME FRAME. VISIBILITY OF 3-5 MILES IN THIS RAIN/SNOW MIX WILL LIKELY BE OBSERVED BUT WITH VISIBILITY EXPECTED TO FALL TO 1-2 MILES IN THE SNOW. BRIEF BURSTS OF HEAVIER SNOW CANT BE RULED OUT THIS AFTERNOON...BUT ONCE AGAIN PREVAILING VIS STAYING AROUND 1-2 MILES. THIS SNOW SHOULD TAPER OFF BY AROUND 23Z...BUT LINGER OVER THE GYY TERMINAL INTO THE EVENING AS LAKE EFFECT SNOW SHOWERS COULD COME RATHER CLOSE TO THE TERMINAL. ANY HEAVIER LAKE EFFECT SNOW SHOWERS SHOULD REMAIN TO THE EAST OF GYY...BUT WILL NEED TO CONTINUE TO MONITOR THE POSSIBILITY FOR A BRIEF/STRAY SNOW SHOWER TO INCH CLOSE TO THE TERMINAL. CEILINGS HAVE BEEN RAPIDLY DROPPING AT THIS HOUR AS WELL...WITH MVFR CEILINGS IN PLACE. DO EXPECT A CONTINUED DOWNWARD TREND IN CEILINGS WILL IFR CEILINGS LIKELY LATER THIS AFTERNOON. WITH THE DEPARTING PRECIP LATE THIS AFTERNOON...EXPECT CEILINGS TO SLOWLY IMPROVE BUT THEN IMPROVE SIGNIFICANTLY BY EARLY EVENING. NORTH NORTHWEST WINDS HAVE BEEN SLOW TO INCREASE TODAY...BUT WITH INCREASED SPEEDS/GUSTS STILL EXPECTED INTO THE AFTERNOON AND EARLY EVENING. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM HIGH CONFIDENCE WITH PRECIP TRENDS/TIMING THIS AFTERNOON. * MEDIUM HIGH CONFIDENCE WITH CEILING TRENDS. * HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...MAINLY VFR. JUST EAST OF TERMINALS MVFR CIGS AND PSBL LAKE EFFECT CLOUDS. WEDNESDAY THROUGH THURSDAY...VFR. FRIDAY...MVFR POSSIBLE WITH CHC OF LIGHT RAIN/SNOW BEFORE DAYBREAK. THEN CHC OF LIGHT RAIN AFT DAYBREAK. SATURDAY...CHC OF RAIN AND MVFR CIGS. SUNDAY...PSBL MVFR CIGS WITH CHC OF RAIN. BEACHLER && .MARINE... 338 PM CST A COLD FRONT PUSHED DOWN THE LENGTH OF LAKE MI DURING LATE OVERNIGHT AND THIS MORNING WITH WINDS SHIFTING TO OUT OF THE NW AND N WITH 35 KT GALES. WINDS HAD FALLEN TO A BIT BELOW GALE FORCE ON THE N AND CENTRAL PORTIONS OF THE LAKE AT MID AFTERNOON...AND ARE EXPECTED TO DO SO ON THE S PORTION LATE THIS AFTERNOON. HOWEVER...A SECOND SURGE OF COLD AIR MOVING ACROSS NORTHERN WI AND THE U.P. OF MI WILL QUICKLY MOVE S DOWN THE LAKE LATE THIS AFTERNOON AND EARLY THIS EVENING WITH WINDS EXPECTED TO INCREASE BACK TO 35 KT GALES BEFORE GRADUALLY DIMINISHING OVERNIGHT AND CONTINUING TO DO SO DURING TUESDAY. WINDS BACK TO W TUE NIGHT AND SW WED...INCREASING TO 35-40 KT GALES AS A LARGE HIGH MOVES EAST-SOUTHEAST FROM THE CENTRAL PLAINS ACROSS THE MID MISSISSIPPI VALLEY AND REACHING THE SOUTHERN APPALACHIANS BY THU. SW GALES WILL CONTINUE THROUGH WED NIGHT INTO THU MORNING AS LOW PRESSURE THAT DEVELOPED OVER ALBERTA TUE DEEPENS AS IT MOVES QUICKLY E TO JAMES BAY BY THU MORNING. WINDS AND WAVES MEETING OR EXCEEDING OF SMALL CRAFT ADVISORY CRITERIA WILL ALONG THE IL SHORE UNTIL LATE TUE EVENING...AND INTO OVERNIGHT TUE. WINDS WILL LIKELY INCREASE BACK TO ABOVE SMALL CRAFT CRITERIA BY WED AFTERNOON. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...LAKE EFFECT SNOW ADVISORY...INZ002-INZ011...9 PM MONDAY TO NOON TUESDAY. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ744-LMZ745-LMZ777- LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM TUESDAY. SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM TUESDAY. SMALL CRAFT ADVISORY...LMZ744-LMZ745...3 AM TUESDAY TO 3 AM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
301 PM CST MON NOV 11 2013 .DISCUSSION... ISSUED 300 PM CST MON NOV 11 2013 MUCH COLDER AIR WILL ARRIVE TONIGHT AND MODIFY ONLY SLIGHTLY THROUGH WEDNESDAY MORNING. A WARMING TREND STILL LOOKS LIKELY LATER THIS WEEK AS THE MID WEEK UPPER RIDGE SHIFTS EAST OF IL AND A SOUTHWEST FLOW DEVELOPS ALOFT. THE WARMING WILL BECOME MORE NOTICEABLE NEXT WEEKEND AS HIGHS RETURN TO THE 50S ON SATURDAY AND AROUND 60 ON SUNDAY. RAINY CONDITIONS ARE FORECAST FOR AT LEAST THE LAST HALF OF NEXT WEEKEND, AS A LONG WAVE TROUGH DIGS INTO THE PLAINS. THE TIMING OF THAT SYSTEM IS STILL UNCERTAIN, BUT ANOTHER COLD PUSH OF AIR IS PROJECTED BEHIND THAT UPPER TROUGH FOR EITHER MONDAY (GFS) OR TUESDAY (ECMWF). SHORT TERM...TONIGHT THROUGH THURSDAY. THE STRONG COLD FRONT WILL QUICKLY DEPART TO THE SOUTHEAST BY EVENING, WITH POST-FRONTAL RAIN QUICKLY CHANGING TO SNOW. MOST UPSTREAM REPORTS HAVE INDICATED THE SNOW MELTED AS IT FELL, BUT SLIPPERY CONDITIONS DEVELOPED AS AIR TEMPS PLUMMETED BELOW FREEZING. SOME ACCIDENTS HAVE BEEN REPORTED DUE TO ICY SPOTS ON ROADS. THE BAND OF SNOW SEEMS TO BE EXPANDING IN DEPTH BETWEEN 19Z-20Z, AND THAT COULD KEEP SNOW FLYING FOR UP TO 4 HOURS OR SO ONCE IT DEVELOPS. HOWEVER, MEASURABLE SNOW IS NOT REALLY EXPECTED FOR MORE THAN A FEW MINUTES UNLESS A SNOW BURST OVERCOMES THE WARM GROUND FOR A WHILE. VISIBILITIES HAVE DIPPED TO 1/4 MILE IN SNOW AT TIMES UPSTREAM IN IOWA/WISCONSIN, MAINLY DUE TO WINDY CONDITIONS DURING THE SNOWFALL AND NOT DUE TO THE HEAVY NATURE OF THE SNOWFALL. THE MAIN AXIS OF PRECIPITATION SEEMS WELL CORRELATED TO THE 850MB FRONTOGENESIS. RADAR IMAGES SHOW A MORE PRONOUNCED BAND OF PRECIPITATION CORRELATING TO THE CHANGE-OVER TO SNOW, JUST PASSING OVER DVN AT 20Z. LAPS SOUNDINGS SHOW THE CHANGE-OVER ALSO CORRELATING TO A 925MB TEMP OF -2C. TIMING THOSE CONDITIONS AND THAT BAND INTO OUR AREA WOULD PUT THE CHANGE TO SNOW IN GBG AROUND 330 PM, PIA AT 430 PM, BMI BY 515 PM, LINCOLN AT 6 PM, CMI/SPI AT 630 PM, EFFINGHAM AROUND 9 PM, AND LAWRENCEVILLE AROUND 1015 PM. DEPENDING ON THE PROGRESSION OF 850MB FGEN, SNOW WILL GENERALLY LAST FROM 2 TO 4 HOURS AFTER THOSE TIMES. AREAS SOUTHWEST OF A LINE FROM RUSHVILLE TO EFFINGHAM WILL SEE WEAKER FORCING, BASED ON THE LATEST RAP OUTPUT, SO PRECIP AMOUNTS SHOULD BE LOWER IN THOSE AREAS. SUBSIDENCE AND DRY AIR SHOULD HELP TO SHUT DOWN THE PRECIPTATION IN OUR SOUTHEASTERN AREAS BETWEEN 2-3 AM. SKIES SHOULD BEGIN TO CLEAR ABOUT 4 TO 5 HOURS AFTER THE PRECIPITATION ENDS, BASED ON SATELLITE TRENDS AND FORECAST RH IN THE LOW TO MID LEVELS. LOWS WILL HAVE A CHANCE TO DROP INTO THE UPPER TEENS W OF I-55, WITH LOW TO MID 20S ELSEWHERE. DRY AND UNSEASONABLY COLD AIR WILL LIMIT HIGHS ON TUESDAY TO THE LOW 30S NEAR GBG AND UPPER 30S NEAR LWV. CLEAR SKIES AND LIGHT WINDS UNDER THE SURFACE RIDGE AXIS ON TUESDAY NIGHT SHOULD ALLOW ALL AREAS TO DROP INTO THE TEENS FOR LOWS. SOME WARMING IN THE 850MB LAYER SHOULD HELP TO TEMPER LOWS FROM DROPPING INTO THE 10-15 DEG RANGE. A COUPLE OF TRADITIONAL COLD SPOTS MAY END UP THAT COLD. WEDNESDAY WILL SEE THE SURFACE RIDGE SLIDE EAST OF IL AND RISING HEIGHTS ALOFT AIDING IN WARMING THROUGH A DEEP COLUMN. THE AIR TEMPS NEAR THE GROUND WILL BE SLOW TO REBOUND, BUT A STEADY RISE BY 5 DEGREES FOR HIGHS IS EXPECTED WED AND THURSDAY. LONG TERM...THURSDAY NIGHT THROUGH MONDAY. NORTHERN AND SOUTHERN STREAM JET INTERACTIONS WILL AID IN CARVING A TROUGH IN THE ROCKIES AND WESTERN PLAINS ON THURSDAY. INCREASING SOUTHWEST FLOW IN THE LEE OF THE TROUGH WILL PUSH MOISTURE AND CLOUDS INTO ILLINOIS THURSDAY NIGHT. WE COULD SEE ENOUGH RISING MOTION FROM WARM ADVECTION TO GENERATE A FEW RAIN SHOWERS WEST OF I-55. CHANCE POPS WERE ONLY INCLUDED WEST OF RUSHVILLE TO LACON IN THE NW. THE RAIN MAY CHANGE TO SNOW NORTH OF PEORIA LATE THUR NIGHT, BUT PRECIP AMOUNTS WILL BE LIGHT AND NO ACCUMULATION IS EXPECTED. A 500MB SHORTWAVE AND THE CORRESPONDING SURFACE TROUGH WILL PASS ACROSS IL ON FRIDAY, WITH ADDITIONAL RAIN SHOWERS POSSIBLE. WE ONLY USED SLIGHT CHANCE POPS FOR FRIDAY AS THE SYSTEM WILL BE WEAKENING AS IT PUSHES INTO A RIDGE OVER THE EASTERN STATES. THE UPPER TROUGH ACROSS THE WESTERN HALF OF THE LOWER 48 IS EXPECTED TO AMPLIFY NEXT WEEKEND, INCREASING THE MOISTURE RETURN INTO IL. A LOW LEVEL JET IS EXPECTED TO INTENSIFY BY SUNDAY MORNING AND NOSE INTO IL, TRIGGERING MORE WIDESPREAD SHOWERS STARTING AS EARLY AS SATURDAY NIGHT. SHOWERS MAY LINGER THROUGH MONDAY PER THE GFS, OR THROUGH TUES IF THE SLOWER ECMWF VERIFIES. SHIMON && .AVIATION... ISSUED 1120 AM CST MON NOV 11 2013 INITIAL WIND SHIFT ASSOCIATED WITH FRONTAL BOUNDARY JUST STARTING TO COME THROUGH KBMI/KSPI, AND SHOULD GO THROUGH KDEC/KCMI OVER THE NEXT COUPLE HOURS. WILL SEE NORTHWEST WINDS START TO PICK UP SIGNIFICANTLY OVER THE NEXT FEW HOURS BEHIND THE FRONT, AS THE COLDER AIR RUSHES INTO THE AREA, WITH GUSTS TO AROUND 25 KNOTS LIKELY. LIGHT RAIN SHOULD START SPREADING IN FROM THE NORTH OVER THE NEXT COUPLE HOURS. FORECAST SOUNDINGS START TO SUPPORT A RAIN/SNOW MIX AROUND KPIA/KBMI BETWEEN 21-24Z AND FROM KSPI-KCMI AROUND 00Z BEFORE SWITCHING OVER TO ALL SNOW. CEILINGS EXPECTED TO DROP TO AROUND 1000-1500 FEET WITH THE PRECIPITATION, ALTHOUGH MAY DIP BELOW 1000 FEET IN THE HEAVIER SNOW SHOWERS. THE GUSTY WINDS WILL DIMINISH LATE EVENING, BUT GENERALLY REMAIN ABOVE 10 KNOTS THE REMAINDER OF THE FORECAST PERIOD. RATHER SHARP CLEARING LINE, CURRENTLY EVIDENT FROM NORTH DAKOTA TO NORTHERN WISCONSIN, SHOULD COME THROUGH THE TAF SITES LATE THIS EVENING, WITH MAINLY CLEAR SKIES INTO TUESDAY MORNING. HAVE KEPT SOME CLOUDINESS CONTINUING LATER NEAR KCMI, WHICH WILL LIKELY BE ON THE PERIPHERY OF LAKE EFFECT SNOWS THAT WILL AFFECT NORTHWEST INDIANA. GEELHART && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...CORRECTED
NWS LINCOLN IL
305 PM CST MON NOV 11 2013 .DISCUSSION... ISSUED 300 PM CST MON NOV 11 2013 MUCH COLDER AIR WILL ARRIVE TONIGHT AND MODIFY ONLY SLIGHTLY THROUGH WEDNESDAY MORNING. A WARMING TREND STILL LOOKS LIKELY LATER THIS WEEK AS THE MID WEEK UPPER RIDGE SHIFTS EAST OF IL AND A SOUTHWEST FLOW DEVELOPS ALOFT. THE WARMING WILL BECOME MORE NOTICEABLE NEXT WEEKEND AS HIGHS RETURN TO THE 50S ON SATURDAY AND AROUND 60 ON SUNDAY. RAINY CONDITIONS ARE FORECAST FOR AT LEAST THE LAST HALF OF NEXT WEEKEND, AS A LONG WAVE TROUGH DIGS INTO THE PLAINS. THE TIMING OF THAT SYSTEM IS STILL UNCERTAIN, BUT ANOTHER COLD PUSH OF AIR IS PROJECTED BEHIND THAT UPPER TROUGH FOR EITHER MONDAY (GFS) OR TUESDAY (ECMWF). SHORT TERM...TONIGHT THROUGH THURSDAY. THE STRONG COLD FRONT WILL QUICKLY DEPART TO THE SOUTHEAST BY EVENING, WITH POST-FRONTAL RAIN QUICKLY CHANGING TO SNOW. MOST UPSTREAM REPORTS HAVE INDICATED THE SNOW MELTED AS IT FELL, BUT SLIPPERY CONDITIONS DEVELOPED AS AIR TEMPS PLUMMETED BELOW FREEZING. SOME ACCIDENTS HAVE BEEN REPORTED DUE TO ICY SPOTS ON ROADS. THE BAND OF SNOW SEEMS TO BE EXPANDING IN DEPTH BETWEEN 19Z-20Z, AND THAT COULD KEEP SNOW FLYING FOR UP TO 4 HOURS OR SO ONCE IT DEVELOPS. HOWEVER, MEASURABLE SNOW IS NOT REALLY EXPECTED FOR MORE THAN A FEW MINUTES UNLESS A SNOW BURST OVERCOMES THE WARM GROUND FOR A WHILE. VISIBILITIES HAVE DIPPED TO 1/4 MILE IN SNOW AT TIMES UPSTREAM IN IOWA/WISCONSIN, MAINLY DUE TO WINDY CONDITIONS DURING THE SNOWFALL AND NOT DUE TO THE HEAVY NATURE OF THE SNOWFALL. THE MAIN AXIS OF PRECIPITATION SEEMS WELL CORRELATED TO THE 850MB FRONTOGENESIS. RADAR IMAGES SHOW A MORE PRONOUNCED BAND OF PRECIPITATION CORRELATING TO THE CHANGE-OVER TO SNOW, JUST PASSING OVER DVN AT 20Z. LAPS SOUNDINGS SHOW THE CHANGE-OVER ALSO CORRELATING TO A 925MB TEMP OF -2C. TIMING THOSE CONDITIONS AND THAT BAND INTO OUR AREA WOULD PUT THE CHANGE TO SNOW IN GBG AROUND 330 PM, PIA AT 430 PM, BMI BY 515 PM, LINCOLN AT 6 PM, CMI/SPI AT 630 PM, EFFINGHAM AROUND 9 PM, AND LAWRENCEVILLE AROUND 1015 PM. DEPENDING ON THE PROGRESSION OF 850MB FGEN, SNOW WILL GENERALLY LAST FROM 2 TO 4 HOURS AFTER THOSE CHANGE-OVER TIMES. AREAS SOUTHWEST OF A LINE FROM RUSHVILLE TO EFFINGHAM WILL SEE WEAKER FORCING, BASED ON THE LATEST RAP OUTPUT, SO PRECIP AMOUNTS SHOULD BE LOWER IN THOSE AREAS. SUBSIDENCE AND DRY AIR SHOULD HELP TO SHUT DOWN THE PRECIPTATION IN OUR SOUTHEASTERN AREAS BETWEEN 2-3 AM. SKIES SHOULD BEGIN TO CLEAR ABOUT 4 TO 5 HOURS AFTER THE PRECIPITATION ENDS, BASED ON SATELLITE TRENDS AND FORECAST RH IN THE LOW TO MID LEVELS. LOW TEMPS WILL HAVE A CHANCE TO DROP INTO THE UPPER TEENS W OF I-55, WITH LOW TO MID 20S ELSEWHERE. DRY AND UNSEASONABLY COLD AIR WILL LIMIT HIGHS ON TUESDAY TO THE LOW 30S NEAR GBG AND UPPER 30S NEAR LWV. CLEAR SKIES AND LIGHT WINDS UNDER THE SURFACE RIDGE AXIS ON TUESDAY NIGHT SHOULD ALLOW ALL AREAS TO DROP INTO THE TEENS FOR LOWS. SOME WARMING IN THE 850MB LAYER SHOULD HELP TO TEMPER LOWS FROM DROPPING INTO THE 10-15 DEG RANGE. A COUPLE OF TRADITIONAL COLD SPOTS MAY END UP THAT COLD. WEDNESDAY WILL SEE THE SURFACE RIDGE SLIDE EAST OF IL AND RISING HEIGHTS ALOFT AIDING IN WARMING THROUGH A DEEP COLUMN. THE AIR TEMPS NEAR THE GROUND WILL BE SLOW TO REBOUND, BUT A STEADY RISE BY 5 DEGREES FOR HIGHS IS EXPECTED WED AND THURSDAY. LONG TERM...THURSDAY NIGHT THROUGH MONDAY. NORTHERN AND SOUTHERN STREAM JET INTERACTIONS WILL AID IN CARVING A TROUGH IN THE ROCKIES AND WESTERN PLAINS ON THURSDAY. INCREASING SOUTHWEST FLOW IN THE LEE OF THE TROUGH WILL PUSH MOISTURE AND CLOUDS INTO ILLINOIS THURSDAY NIGHT. WE COULD SEE ENOUGH RISING MOTION FROM WARM ADVECTION TO GENERATE A FEW RAIN SHOWERS WEST OF I-55. CHANCE POPS WERE ONLY INCLUDED WEST OF RUSHVILLE TO LACON IN THE NW. THE RAIN MAY CHANGE TO SNOW NORTH OF PEORIA LATE THUR NIGHT, BUT PRECIP AMOUNTS WILL BE LIGHT AND NO ACCUMULATION IS EXPECTED. A 500MB SHORTWAVE AND THE CORRESPONDING SURFACE TROUGH WILL PASS ACROSS IL ON FRIDAY, WITH ADDITIONAL RAIN SHOWERS POSSIBLE. WE ONLY USED SLIGHT CHANCE POPS FOR FRIDAY AS THE SYSTEM WILL BE WEAKENING AS IT PUSHES INTO A RIDGE OVER THE EASTERN STATES. THE UPPER TROUGH ACROSS THE WESTERN HALF OF THE LOWER 48 IS EXPECTED TO AMPLIFY NEXT WEEKEND, INCREASING THE MOISTURE RETURN INTO IL. A LOW LEVEL JET IS EXPECTED TO INTENSIFY BY SUNDAY MORNING AND NOSE INTO IL, TRIGGERING MORE WIDESPREAD SHOWERS STARTING AS EARLY AS SATURDAY NIGHT. SHOWERS MAY LINGER THROUGH MONDAY PER THE GFS, OR THROUGH TUES IF THE SLOWER ECMWF VERIFIES. SHIMON && .AVIATION... ISSUED 1120 AM CST MON NOV 11 2013 INITIAL WIND SHIFT ASSOCIATED WITH FRONTAL BOUNDARY JUST STARTING TO COME THROUGH KBMI/KSPI, AND SHOULD GO THROUGH KDEC/KCMI OVER THE NEXT COUPLE HOURS. WILL SEE NORTHWEST WINDS START TO PICK UP SIGNIFICANTLY OVER THE NEXT FEW HOURS BEHIND THE FRONT, AS THE COLDER AIR RUSHES INTO THE AREA, WITH GUSTS TO AROUND 25 KNOTS LIKELY. LIGHT RAIN SHOULD START SPREADING IN FROM THE NORTH OVER THE NEXT COUPLE HOURS. FORECAST SOUNDINGS START TO SUPPORT A RAIN/SNOW MIX AROUND KPIA/KBMI BETWEEN 21-24Z AND FROM KSPI-KCMI AROUND 00Z BEFORE SWITCHING OVER TO ALL SNOW. CEILINGS EXPECTED TO DROP TO AROUND 1000-1500 FEET WITH THE PRECIPITATION, ALTHOUGH MAY DIP BELOW 1000 FEET IN THE HEAVIER SNOW SHOWERS. THE GUSTY WINDS WILL DIMINISH LATE EVENING, BUT GENERALLY REMAIN ABOVE 10 KNOTS THE REMAINDER OF THE FORECAST PERIOD. RATHER SHARP CLEARING LINE, CURRENTLY EVIDENT FROM NORTH DAKOTA TO NORTHERN WISCONSIN, SHOULD COME THROUGH THE TAF SITES LATE THIS EVENING, WITH MAINLY CLEAR SKIES INTO TUESDAY MORNING. HAVE KEPT SOME CLOUDINESS CONTINUING LATER NEAR KCMI, WHICH WILL LIKELY BE ON THE PERIPHERY OF LAKE EFFECT SNOWS THAT WILL AFFECT NORTHWEST INDIANA. GEELHART && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
300 PM CST MON NOV 11 2013 .DISCUSSION... 259 PM CST SEVERAL NEAR TERM FORECAST CONCERNS AND CHALLENGES WITH PRECIPITATION ENDING FROM NORTH TO SOUTH INTO THE EVENING...WITH LAKE EFFECT SNOW DEVELOPING THROUGH THE EVENING IMPACTING PORTIONS OF NORTHWEST INDIANA TO SOME DEGREE THROUGH THE OVERNIGHT. AFTERNOON WATER VAPOR IMAGERY SHOWS A DEEP UPPER LOW SPINNING OVER SOUTHERN JAMES BAY AS PART OF A BROAD UPPER TROUGH SPREADING ACROSS THE EASTERN HALF OF THE COUNTRY. RIDGING IS BUILDING OVER THE PACIFIC NORTHWEST AND BRITISH COLUMBIA AS ANOTHER UPPER LOW SPINS OVER THE WEST COAST WITH YET ANOTHER TROUGH JUST TO ITS WEST. AT THE SURFACE...LOW PRESSURE ASSOCIATED WITH THE JAMES BAY UPPER LOW IS MOVING INTO NORTHERN QUEBEC WITH A COLD FRONT TRAILING IT TO THE SOUTHWEST AND HAVING EXITED THE SOUTHERN CWA. STRONG HIGH PRESSURE IS SETTLING SOUTHWARD INTO THE PLAINS AND WESTERN GREAT LAKES. THIS EVENING...CURRENT POST FRONTAL BAND OF PRECIPITATION CONTINUES TO GRADUALLY WORK SOUTHWARD ACROSS THE CENTRAL AND SOUTHERN CWA. THIS BAND WILL CONTINUE SOUTHWARD THROUGH EARLY EVENING BEFORE ENDING ACROSS THE SOUTHERN CWA BY MID EVENING OR SO. FAIRLY INTENSE SNOWFALL PRODUCING VISIBILITY UNDER A MILE AT TIMES WILL CONTINUE AS THE COLDER AIR SPREAD SOUTH...WITH AREAS THAT ARE CURRENTLY RAIN CHANGING OVER. HAVE HAD REPORTS OF AROUND A HALF INCH OF ACCUMULATION ON GRASSY AND OTHER NON PAVED SURFACES AND EXPECT THAT THIS WILL CONTINUE TO BE THE TREND UNTIL THE SNOW WINDS DOWN. THE MAIN CONCERN WITH THIS WILL BE TEMPS FALLING BELOW FREEZING ACROSS AREAS THAT HAVE NOT ALREADY DONE SO THROUGH SUNSET. PRECIP MAY END BEFORE THIS OCCURS IN SOME AREAS BUT THIS WILL SET UP POTENTIAL FOR RESIDUAL MOISTURE ON VARIOUS SURFACES TO FREEZE BEFORE DRYING SO MOTORISTS AND PEDESTRIANS SHOULD BE ALERT. TONIGHT AND TUESDAY...THE FOCUS WILL BE ON LAKE EFFECT SNOW PLACEMENT TONIGHT THROUGH TUESDAY MORNING. THE UPPER LOW WILL CONTINUE EASTWARD TO THE GULF OF ST. LAWRENCE BY TUESDAY MORNING WITH AN ASSOCIATED TROUGH AXIS CROSSING THE LOCAL AREA. NORTHERLY LOW AND MID LEVEL FLOW WILL BE IN PLACE ACROSS LAKE MICHIGAN THIS EVENING AND OVERNIGHT WITH CONTINUED COLD ADVECTION BRINGING H85 TEMPS DOWN TO AROUND -12 C CREATING LAKE TO H85 DELTA-TS OF 20+C. GENERATING LAKE EFFECT WILL NOT BE A PROBLEM...ITS THE PLACEMENT THAT IS THE MAIN CHALLENGE. MEAN LOW LEVEL FLOW THIS EVENING WILL START OUT NORTHWESTERLY ACROSS NORTHERN PORTIONS OF THE LAKE AND NORTHERLY SOUTH AS THE COLDER AIR CONTINUES TO ADVECT IN. WITH TIME...THE MEAN FLOW WILL GAIN MORE OF A WEST COMPONENT/THOUGH STILL REMAINING NORTHWESTERLY OVERALL/ INTO TUESDAY MORNING. THE INITIAL CONVERGENCE LOOKS TO SET UP ACROSS NORTHERN SECTIONS OF THE LAKE CLOSER TO THE MICHIGAN SHORE BASED ON THE NORTHWEST DIRECTION AND FAIRLY STRONG SPEEDS FOCUSING FRICTIONAL CONVERGENCE CLOSER TO SHORE. THE BAND MAY ARC SOUTH OR SOUTHWEST AS IT DEVELOPS SOUTHWARD AS THE FLOW TURNS MORE NORTHERLY...BUT MAY STILL REMAIN FAIRLY CLOSE TO THE MICHIGAN SHORELINE. AM CONCERNED BY THE NEARLY DUE NORTH DIRECTION THIS EVENING BUT DEVELOPMENT OF MORE ORGANIZED BANDS MAY HOLD OFF UNTIL CLOSER TO MIDNIGHT. THIS MAY RESULT IN PORTER COUNTY AND EVEN PORTIONS OF JASPER COUNTY SEEING A PERIOD OF DECENT SNOWFALL LATER THIS EVENING AND EARLY TONIGHT BEFORE WINDS TURN SLIGHTLY NORTHWEST PUSHING THE BAND FURTHER EAST TOWARD DAYBREAK. MOST OF THE HIGH RES GUIDANCE HAS BEEN BULLISH ON KEEPING THE BAND CLOSER TO THE MICHIGAN SHORE AND INTO LAPORTE AND BERRIEN COUNTIES AND EVEN POINTS FURTHER EAST...WITH MUCH LESS ACTIVITY IN PORTER/JASPER. AM WONDERING IF THEY ARE A LITTLE TOO BULLISH ON HOW FAR EAST THE FOCUS BECOMES. WITH A STRONG NORTH COMPONENT HAVE A HARD TIME SEEING THE BAND DEVELOPING ALL THE WAY ON THE EAST SIDE OF THE LAKE AND MORE OR LESS STAYING THERE UNLESS TIMING OF ACTUAL PLUME DEVELOPMENT IS DELAYED UNTIL WINDS START TO TURN MORE NORTHWEST. INTERESTINGLY...SOME OF THE LATEST RAP GUIDANCE FALLS MORE IN LINE WITH THIS THOUGHT PROCESS. WHILE THERE IS SIGNIFICANT BUST POTENTIAL HERE...WILL GO AHEAD AND ISSUE A LAKE EFFECT SNOW ADVISORY FOR PORTER AND JASPER HIGHLIGHTING THE LATE EVENING AND OVERNIGHT HOURS AS THE PERIOD OF BEST HEAVY SNOW POTENTIAL ACROSS MAINLY THE EAST HALF OF EACH COUNTY. SNOWFALL RATES MAY BE QUITE INTENSE ON THE ORDER OF SEVERAL INCHES PER HOUR BUT THE DURATION IS STILL A QUESTION MARK. COMBINE THIS WITH GUSTY WINDS FAIRLY ROUGH CONDITIONS MAY DEVELOP ASSUMING THE BAND AFFECTS THESE AREAS. STILL CANNOT RULE OUT WARNING LEVEL SNOWS OVER 6 INCHES BUT WITH A FAIR AMOUNT OF SUPPORT FOR LESSER AMOUNTS HAVE A HARD TIME GOING WITH A WARNING AT THIS POINT. FOLLOWING THE IDEA THAT THE BAND WILL INITIALLY IMPACT PORTER/JASPER THEN SHIFT EASTWARD FEEL A BIT MORE COMFORTABLE GOING WITH AN ADVISORY THAN JUST KEEPING THE WATCH. THE EVENING SHIFT WILL NEED TO MONITOR CLOSELY. BEYOND THAT...LOWS WILL FALL INTO THE LOW TO MID 20S TONIGHT WITH READINGS CLOSER TO 30 NEAR AND DOWNWIND OF THE LAKE. DRY CONDITIONS WILL PERSIST ACROSS THE MAJORITY OF THE AREA WITH LAKE EFFECT SHOWERS ENDING EAST TUESDAY. HIGHS WILL ONLY MAKE IT INTO LOW TO MID 30S. WEDNESDAY AND BEYOND...DID NOT HAVE A WHOLE LOT OF TIME TO LOOK FURTHER AHEAD IN THE FORECAST PERIOD BUT HIGH PRESSURE WILL BE SETTLING INTO THE LOWER OHIO VALLEY WEDNESDAY AS THE WESTERN UPPER RIDGE IS SHUNTED EASTWARD. THIS WILL ALLOW MODEST WARM ADVECTION TO DEVELOP IN THE MID LEVELS WITH A STEADY SOUTHWEST WIND AT THE SURFACE AS THE HIGH SHIFTS EASTWARD. MAY BE A LITTLE TOO CONSERVATIVE WITH UPPER 30S HIGHS WITH ANY SNOWPACK IN NW INDIANA LIKELY KEEPING THINGS IN THE 30S REGARDLESS. THE UPPER RIDGE WILL BE BROKEN DOWN AS IT TRANSLATES EASTWARD AS A FAIRLY BROAD LONGWAVE TROUGH MOVES ACROSS THE ROCKIES AND INTO THE PLAINS THURSDAY. A WEAK SURFACE TROUGH IS EXPECTED TO ACCOMPANY THIS AND BRING A WEAK COOL FRONT ACROSS THE AREA THURSDAY NIGHT OR FRIDAY WITH A LOW CHANCE FOR RAIN/SNOW AT NIGHT AND SHOWERS DURING THE DAY. LOW AMPLITUDE FLOW WILL THEN MOVE ACROSS THE AREA SATURDAY WITH AN AMPLIFYING TROUGH SPREADING IN LATER IN THE WEEKEND AND EARLY NEXT WEEK. A SURFACE LOW IS FORECAST TO DEEPEN AS THE TROUGH AMPLIFIES BUT ECMWF/GFS ARE AT ODDS ON HOW QUICKLY THIS OCCURS. A WARMUP SHOULD OCCUR IN THE SOUTHERLY FLOW AHEAD OF THE LOW BUT THIS MAY BE BRIEF IF A FASTER SOLUTION PANS OUT. EITHER WAY MOIST SOUTHERLY FLOW POINTS TOWARD INCREASING PRECIP CHANCES SUNDAY WHICH MAY CONTINUE THROUGH MONDAY IF THE SLOWER SOLUTION PANS OUT. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * RAIN/SNOW MIX QUICKLY TRANSITIONING OVER TO ALL SNOW OVER THE NEXT HOUR...WITH VISIBILITY DROPPING TO AROUND 1 MILE AT TIMES. * IFR CEILINGS THIS AFTERNOON. * NNW WINDS INCREASING WITH GUSTS AROUND 20KT. RODRIGUEZ //DISCUSSION...UPDATED 18Z... DETERIORATING CONDITIONS ONGOING ACROSS THE TERMINALS EARLY THIS AFTERNOON...ESPECIALLY NEAR RFD WHERE THE RAIN/SNOW MIX QUICKLY TRANSITIONED OVER TO ALL SNOW. THIS TREND WILL CONTINUE WITH THE REMAINING TERMINALS OVER THE NEXT 1-2 HOURS...AND GYY BY THE 21Z TIME FRAME. VISIBILITY OF 3-5 MILES IN THIS RAIN/SNOW MIX WILL LIKELY BE OBSERVED BUT WITH VISIBILITY EXPECTED TO FALL TO 1-2 MILES IN THE SNOW. BRIEF BURSTS OF HEAVIER SNOW CANT BE RULED OUT THIS AFTERNOON...BUT ONCE AGAIN PREVAILING VIS STAYING AROUND 1-2 MILES. THIS SNOW SHOULD TAPER OFF BY AROUND 23Z...BUT LINGER OVER THE GYY TERMINAL INTO THE EVENING AS LAKE EFFECT SNOW SHOWERS COULD COME RATHER CLOSE TO THE TERMINAL. ANY HEAVIER LAKE EFFECT SNOW SHOWERS SHOULD REMAIN TO THE EAST OF GYY...BUT WILL NEED TO CONTINUE TO MONITOR THE POSSIBILITY FOR A BRIEF/STRAY SNOW SHOWER TO INCH CLOSE TO THE TERMINAL. CEILINGS HAVE BEEN RAPIDLY DROPPING AT THIS HOUR AS WELL...WITH MVFR CEILINGS IN PLACE. DO EXPECT A CONTINUED DOWNWARD TREND IN CEILINGS WILL IFR CEILINGS LIKELY LATER THIS AFTERNOON. WITH THE DEPARTING PRECIP LATE THIS AFTERNOON...EXPECT CEILINGS TO SLOWLY IMPROVE BUT THEN IMPROVE SIGNIFICANTLY BY EARLY EVENING. NORTH NORTHWEST WINDS HAVE BEEN SLOW TO INCREASE TODAY...BUT WITH INCREASED SPEEDS/GUSTS STILL EXPECTED INTO THE AFTERNOON AND EARLY EVENING. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM HIGH CONFIDENCE WITH PRECIP TRENDS/TIMING THIS AFTERNOON. * MEDIUM HIGH CONFIDENCE WITH CEILING TRENDS. * HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...MAINLY VFR. JUST EAST OF TERMINALS MVFR CIGS AND PSBL LAKE EFFECT CLOUDS. WEDNESDAY THROUGH THURSDAY...VFR. FRIDAY...MVFR POSSIBLE WITH CHC OF LIGHT RAIN/SNOW BEFORE DAYBREAK. THEN CHC OF LIGHT RAIN AFT DAYBREAK. SATURDAY...CHC OF RAIN AND MVFR CIGS. SUNDAY...PSBL MVFR CIGS WITH CHC OF RAIN. BEACHLER && .MARINE... 201 AM CST MARINE CONCERNS... GALES DEVELOPING THIS MORNING ACROSS THE NORTHERN HALF OF THE LAKE...THEN OVERSPREADING THE REMAINDER OF THE LAKE. FOR MOST OF THE ILLINOIS AND FAR WESTERN INDIANA NEARSHORE WATERS WINDS SHOULD REMAIN UNDER GALES...WHILE EAST OF GARY GALES WILL DEVELOP LATER TODAY. GALES COME TO AN END MID-MORNING TUE...ALTHOUGH FOR THE NEARSHORE WATERS HAZARDOUS WAVES WILL LIKELY PERSIST INTO TUE EVENING WITH THE VERY COLD AIR SLIDING ACROSS THE LAKE AND PERSISTING NORTHWEST WINDS. STRONG COLD FRONT WILL SLIDE SOUTHEAST ACROSS THE LAKE THIS MORNING...WITH WINDS QUICKLY FLIPPING FROM SOUTHWEST TO NORTHWEST THEN NORTH BEHIND THE FRONT. IN ADDITION A VERY TIGHT PRESSURE GRADIENT WILL BE ASSOCIATED WITH THE BOUNDARY...RESULTING IN GALES TO 40 KT. COULD SEE ACROSS THE NORTHERN HALF OF THE LAKE A PERIOD OF GALES TO 45 KT THIS AFTN. FURTHER SOUTH THE GRADIENT IS SLIGHTLY LESS THIS AFTN/EVE...SO HAVE GALES BETWEEN 35-40KT. STRONG CANADIAN HIGH PRESSURE SLIDES SOUTH INTO THE CENTRAL PLAINS TONIGHT...WHICH WILL MAINTAIN THE NORTH FLOW ACROSS THE LAKE TONIGHT INTO TUESDAY. THEN HIGH PRESSURE BEGINS TO PROVIDE AN INFLUENCE ON THE GRADIENT AND ALLOWS THE WINDS TO DIMINISH. HIGH PRESSURE THEN DRIFTS SOUTHEAST OF THE GREAT LAKES...WITH FLOW TURNING WEST THEN SOUTHWESTERLY WED. ANOTHER TROUGH OF LOW PRESSURE IS FORECAST TO DEVELOP OVER THE UPPER MIDWEST...WHICH WILL LIKELY RESULT IN A TIGHTENING GRADIENT AND GALES FOR THE OPEN WATERS WED NIGHT INTO THUR. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...LAKE EFFECT SNOW WATCH...INZ002...9 PM MONDAY TO 6 PM TUESDAY. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM TUESDAY. SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM TUESDAY. GALE WARNING...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 10 PM MONDAY. SMALL CRAFT ADVISORY...LMZ744-LMZ745...10 PM MONDAY TO 3 AM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1246 PM EST MON NOV 11 2013 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 343 AM EST MON NOV 11 2013 MUCH COLDER AIR WILL BE PUSHING INTO THE REGION TODAY AS A COLD FRONT MOVES THROUGH. RAIN IS EXPECTED THIS MORNING...WHICH WILL CHANGE OVER TO SNOW FROM NORTH TO SOUTH THIS AFTERNOON. MOST AREAS WILL SEE LITTLE OR NO SNOW ACCUMULATION...BUT AREAS NEAR HIGHWAY 10 COULD SEE AN INCH OR TWO BY THIS AFTERNOON. TEMPERATURES WILL FALL THROUGH THE 30S THIS AFTERNOON AND INTO THE 20S TONIGHT. LAKE EFFECT SNOW WILL INCREASE INTO TONIGHT AND ADDITIONAL SNOW ACCUMULATIONS ARE LIKELY MAINLY WEST OF U.S. 131. ONE TO LOCALLY FOUR INCHES WILL BE POSSIBLE TONIGHT THROUGH NOON TUESDAY. QUIETER WEATHER IS EXPECTED BY MID WEEK AND TOWARD THE WEEKEND. TEMPERATES WILL WARM TO MAINLY 45 TO 50. && .UPDATE... ISSUED AT 1115 AM EST MON NOV 11 2013 SO FAR (11 AM) THE FORECAST IS ON TRACK. THE RAIN TO SNOW LINE IS JUST BEHIND THE COLD FRONT BUT THE BELOW FREEZING TEMPERATURES REMAIN NORTH OF ROUTE 10 YET. THE RAIN TO SNOW LINE IS NEAR ROUTE 20. I EXPECT THE THE MAIN AREA OF RAIN ASSOCIATED WITH RR QUAD OF TO CONTINUE PROGRESS SOUTH WITH TIME. THE BACK EDGE OF THE PRECIPITATION SHOULD BE MOVING SOUTH THROUGH THE CWA AFTER 2 PM AND REACH THE I-96 AREA BY 4 PM AND I-96 BY 6 PM. AS FOR THE SNOW...THE RAIN/SNOW LINE SHOULD REACH THE GRR AREA BETWEEN 2 PM AND 3 PM... SO MAYBE AN HOUR OR TWO OF WET SNOW BEFORE IT END. I DO NOT SEE MUCH ACCUMULATION OUTSIDE OUR ADVISORY AREA. UP THERE...SINCE UP TO 3 INCHES HAS ALREADY FALLEN... AND THERE SEEMS TO BE A LAKE ENHANCED AREA OF SNOW MOVING SOUTH OVER NORTHERN LOWER MICHIGAN...THEY COULD SEE ANOTHER 1 TO 2 INCHES BRINGING THE STORM TOTAL TO 5 INCHES. I MAY NEED SOME SORT OF LAKE EFFECT SNOW ADVISORY FOR VAN BUREN AND POSSIBLY EXTREME WESTERN ALLEGAN COUNTY AS LATE MODEL RUNS SUGGEST THE SNOW BAND MAY MOVE ON SHORE OVERNIGHT. ALSO THE SNOW BAND OFF LAKE SUPERIOR IS SHOWN BY SEVERAL HIGH RES MODELS TO REACH WELL INTO OUR NORTHERN CWA NEAR US-131 SO I MAY NEED AN ADVISORY UP THERE TOO FOR THE AFTERNOON FORECAST PACKAGE. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 343 AM EST MON NOV 11 2013 A COLD FRONT WAS PUSHING SOUTHEAST ACROSS THE GREEN BAY REGION EARLY THIS MORNING. IT WILL SLIDE ACROSS THE GRR CWA BETWEEN 12Z AND 18Z. TEMPS WILL BE WARM ENOUGH FOR ALL RAIN AHEAD OF THE FRONT...THEN AN HOUR OR TWO AFTER IT PASSES WE SHOULD WET BULB DOWN TO SWITCH OVER THE ALL SNOW. HAVE DECIDED TO POST A WINTER WEATHER ADVISORY FOR LAKE...OSCEOLA AND CLARE COUNTIES. SNOWFALL RATES LATER THIS MORNING INTO EARLY THIS AFTERNOON COULD PRODUCE SLUSHY/SNOW COVERED ROADS THERE...AND BEING THE FIRST SNOW...THERE WILL BE SOME IMPACTS TO ADVISORY DRIVERS. WILL RUN IT THROUGH 3 PM AS IT APPEARS THERE WILL BE A LULL BETWEEN THE END OF THE SYNOPTIC PCPN AND THE BEGINNING OF THE LAKE EFFECT THAT KICKS IN TONIGHT. SHALLOW MOISTURE PROFILES ARE INDICATED BEHIND THE FRONT EARLY THIS EVENING...THEN DEEPER MOISTURE ARRIVES AS A SHORT WAVE SWINGS THROUGH OVERNIGHT. THE LAKE EFFECT SHOULD BEGIN TO RAMP UP AFTER ABOUT 03Z AND SHOULD CONTINUE THE REST OF THE NIGHT AND INTO TUESDAY MORNING. THE MEAN FLOW IS 340-355 THROUGH THIS PERIOD...SO THIS FAVORS AREAS WEST OF U.S. 131. THERE SHOULD BE A DOMINATE BAND SET UP AND DEPENDING ON IT/S EXACT ORIENTATION SOME AREAS NEAR THE POINTS AND WESTERN ALLEGAN AND VAN BUREN COUNTIES COULD GET A DECENT SNOW. I HAVE ONE TO FOUR INCHES INDICATED FOR NOW. WILL NOT ISSUE ANY HEADLINES FOR THE LAKE EFFECT PORTION OF THIS EVENT AS IT SHOULD BE MAINLY TOWARD MIDNIGHT INTO THE OVERNIGHT HOURS AND WE HAVE TIME TO FINE TUNE THINGS. THE SNOWS WILL DIMINISH TUESDAY AFTERNOON AS THE SHORT WAVE PASSES AND THE MOISTURE BECOMES INCREASINGLY SHALLOW. QUIET WEATHER IS EXPECTED FOR TUESDAY NIGHT AND WEDNESDAY WITH SURFACE AND UPPER RIDGING BUILDING IN. TEMPS WILL WARM TO THE LOW AND MID 40S FOR WED. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 343 AM EST MON NOV 11 2013 THE LONG TERM PERIOD WILL FEATURE TEMPERATURES MODERATING ABOVE NORMAL AS A SOUTHWEST FLOW ALOFT DEVELOPS AHEAD OF AN EVOLVING LONGWAVE TROUGH OVER THE WESTERN UNITED STATES. PREDOMINATELY DRY WEATHER WILL PREVAIL THROUGH SATURDAY AS A LARGE DRY SURFACE HIGH BECOMES PARKED OVER THE EASTERN HALF OF THE NATION. THERE IS A LOW CHANCE OF RAIN OR MIXED RAIN AND SNOW SHOWERS WITH THE PASSAGE OF A WEAK FRONTAL BOUNDARY THURSDAY NIGHT AND FRIDAY BUT ONLY VERY LIGHT PRECIP AMOUNTS EXPECTED DUE TO THE OVERALL LACK OF MOISTURE ALONG THE FRONT. A BIG NORTHWARD SURGE OF MOISTURE FROM THE GULF OF MEXICO GETS UNDERWAY SATURDAY NIGHT AND SUNDAY... SO INCREASING CHANCES FOR RAIN EXPECTED ALONG WITH MILD TEMPS IN THE 50S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1246 PM EST MON NOV 11 2013 BIGGEST ITEMS OF INTEREST WITH THE 18Z FCSTS WILL BE CIG/VSBY TRENDS ALONG WITH PCPN TYPE FOR THE FIRST FEW HOURS...THEN CLOUD AND LAKE EFFECT TRENDS FOR THE REMAINDER OF THE PERIOD. RAIN IS ONGOING OVER MOST OF THE TERMINALS AS OF 1730Z WITH KMKG JUST CHANGING TO SNOW AT 17Z. IFR CONDITIONS ARE BEING FOUND ALONG THE PCPN CHANGEOVER LINE THAT SHOULD MOVE THROUGH KGRR JUST AFTER 18Z. WE EXPECT CONDITIONS TO LOWER TO IFR ACROSS THE I-94 TERMINALS THROUGH 21Z AND A CHANGE OVER TO SNOW SHORTLY THEREAFTER. WINDS WILL CHANGE TO COME FROM DUE NORTH ALSO AND GUST A BIT TO AROUND 20 KNOTS OR SO. THE BACK EDGE OF THE WIDESPREAD PCPN IS JUST COMING INTO KLDM AS OF 1740Z. WE EXPECT THIS TO ADVANCE SOUTH THROUGH THE AREA AND CLEAR THE KJXN AREA LAST AROUND 23Z THIS EVENING. CONDITIONS SHOULD IMPROVE TO MVFR AND EVENTUALLY VFR AS THE PCPN ENDS. A LAKE EFFECT BAND OF MODERATE TO INTENSE SNOW SHOWERS SHOULD DEVELOP OVER THE LAKE JUST OFFSHORE THIS EVENING AND TONIGHT AS THE MEAN FLOW SHOULD BE FROM THE NORTH. INLAND LOCATIONS WILL NOT BE AFFECTED...AND IT SHOULD REMAIN JUST WEST OF KMKG. THIS COULD IMPACT ANY FLIGHTS TAKING OFF OR COMING INTO KMKG FROM THE WEST. OTHERWISE...A BKN STRATOCU DECK BASED AROUND 3500 FT SHOULD RULE FOR MOST OTHER AREAS TONIGHT AND THROUGH 18Z TUE. && .MARINE... ISSUED AT 831 AM EST MON NOV 11 2013 I UPDATED THE GRIDS TO SHOW GALES IN THE NEAR SHORE FORECAST THIS AFTERNOON AND TONIGHT. CURRENTLY (830 AM) ONLY ONE STATION NEAR GREEN BAY HAS GUSTS TO GALE FORCE BUT GIVEN THE STRENGTH OF THE COLD ADVECTION OVER A RELATIVELY WARM LAKE MICHIGAN (50 DEGREE) IT WOULD SEEM WE SHOULD SEE THE GALES THIS AFTERNOON AND THIS EVENING. && .HYDROLOGY... ISSUED AT 343 AM EST MON NOV 11 2013 NO ISSUES EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR MIZ038>040. LM...GALE WARNING UNTIL 8 AM EST TUESDAY FOR LMZ844>849. && $$ UPDATE...WDM SYNOPSIS...JK SHORT TERM...JK LONG TERM...MEADE AVIATION...NJJ HYDROLOGY...JK MARINE...WDM
AREA FORECAST DISCUSSION...CORRECTED
NWS GRAND RAPIDS MI
1217 PM EST MON NOV 11 2013 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 343 AM EST MON NOV 11 2013 MUCH COLDER AIR WILL BE PUSHING INTO THE REGION TODAY AS A COLD FRONT MOVES THROUGH. RAIN IS EXPECTED THIS MORNING...WHICH WILL CHANGE OVER TO SNOW FROM NORTH TO SOUTH THIS AFTERNOON. MOST AREAS WILL SEE LITTLE OR NO SNOW ACCUMULATION...BUT AREAS NEAR HIGHWAY 10 COULD SEE AN INCH OR TWO BY THIS AFTERNOON. TEMPERATURES WILL FALL THROUGH THE 30S THIS AFTERNOON AND INTO THE 20S TONIGHT. LAKE EFFECT SNOW WILL INCREASE INTO TONIGHT AND ADDITIONAL SNOW ACCUMULATIONS ARE LIKELY MAINLY WEST OF U.S. 131. ONE TO LOCALLY FOUR INCHES WILL BE POSSIBLE TONIGHT THROUGH NOON TUESDAY. QUIETER WEATHER IS EXPECTED BY MID WEEK AND TOWARD THE WEEKEND. TEMPERATES WILL WARM TO MAINLY 45 TO 50. && .UPDATE... ISSUED AT 1115 AM EST MON NOV 11 2013 SO FAR (11 AM) THE FORECAST IS ON TRACK. THE RAIN TO SNOW LINE IS JUST BEHIND THE COLD FRONT BUT THE BELOW FREEZING TEMPERATURES REMAIN NORTH OF ROUTE 10 YET. THE RAIN TO SNOW LINE IS NEAR ROUTE 20. I EXPECT THE THE MAIN AREA OF RAIN ASSOCIATED WITH RR QUAD OF TO CONTINUE PROGRESS SOUTH WITH TIME. THE BACK EDGE OF THE PRECIPITATION SHOULD BE MOVING SOUTH THROUGH THE CWA AFTER 2 PM AND REACH THE I-96 AREA BY 4 PM AND I-96 BY 6 PM. AS FOR THE SNOW...THE RAIN/SNOW LINE SHOULD REACH THE GRR AREA BETWEEN 2 PM AND 3 PM... SO MAYBE AN HOUR OR TWO OF WET SNOW BEFORE IT END. I DO NOT SEE MUCH ACCUMULATION OUTSIDE OUR ADVISORY AREA. UP THERE...SINCE UP TO 3 INCHES HAS ALREADY FALLEN... AND THERE SEEMS TO BE A LAKE ENHANCED AREA OF SNOW MOVING SOUTH OVER NORTHERN LOWER MICHIGAN...THEY COULD SEE ANOTHER 1 TO 2 INCHES BRINGING THE STORM TOTAL TO 5 INCHES. I MAY NEED SOME SORT OF LAKE EFFECT SNOW ADVISORY FOR VAN BUREN AND POSSIBLY EXTREME WESTERN ALLEGAN COUNTY AS LATE MODEL RUNS SUGGEST THE SNOW BAND MAY MOVE ON SHORE OVERNIGHT. ALSO THE SNOW BAND OFF LAKE SUPERIOR IS SHOWN BY SEVERAL HIGH RES MODELS TO REACH WELL INTO OUR NORTHERN CWA NEAR US-131 SO I MAY NEED AN ADVISORY UP THERE TOO FOR THE AFTERNOON FORECAST PACKAGE. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 343 AM EST MON NOV 11 2013 A COLD FRONT WAS PUSHING SOUTHEAST ACROSS THE GREEN BAY REGION EARLY THIS MORNING. IT WILL SLIDE ACROSS THE GRR CWA BETWEEN 12Z AND 18Z. TEMPS WILL BE WARM ENOUGH FOR ALL RAIN AHEAD OF THE FRONT...THEN AN HOUR OR TWO AFTER IT PASSES WE SHOULD WET BULB DOWN TO SWITCH OVER THE ALL SNOW. HAVE DECIDED TO POST A WINTER WEATHER ADVISORY FOR LAKE...OSCEOLA AND CLARE COUNTIES. SNOWFALL RATES LATER THIS MORNING INTO EARLY THIS AFTERNOON COULD PRODUCE SLUSHY/SNOW COVERED ROADS THERE...AND BEING THE FIRST SNOW...THERE WILL BE SOME IMPACTS TO ADVISORY DRIVERS. WILL RUN IT THROUGH 3 PM AS IT APPEARS THERE WILL BE A LULL BETWEEN THE END OF THE SYNOPTIC PCPN AND THE BEGINNING OF THE LAKE EFFECT THAT KICKS IN TONIGHT. SHALLOW MOISTURE PROFILES ARE INDICATED BEHIND THE FRONT EARLY THIS EVENING...THEN DEEPER MOISTURE ARRIVES AS A SHORT WAVE SWINGS THROUGH OVERNIGHT. THE LAKE EFFECT SHOULD BEGIN TO RAMP UP AFTER ABOUT 03Z AND SHOULD CONTINUE THE REST OF THE NIGHT AND INTO TUESDAY MORNING. THE MEAN FLOW IS 340-355 THROUGH THIS PERIOD...SO THIS FAVORS AREAS WEST OF U.S. 131. THERE SHOULD BE A DOMINATE BAND SET UP AND DEPENDING ON IT/S EXACT ORIENTATION SOME AREAS NEAR THE POINTS AND WESTERN ALLEGAN AND VAN BUREN COUNTIES COULD GET A DECENT SNOW. I HAVE ONE TO FOUR INCHES INDICATED FOR NOW. WILL NOT ISSUE ANY HEADLINES FOR THE LAKE EFFECT PORTION OF THIS EVENT AS IT SHOULD BE MAINLY TOWARD MIDNIGHT INTO THE OVERNIGHT HOURS AND WE HAVE TIME TO FINE TUNE THINGS. THE SNOWS WILL DIMINISH TUESDAY AFTERNOON AS THE SHORT WAVE PASSES AND THE MOISTURE BECOMES INCREASINGLY SHALLOW. QUIET WEATHER IS EXPECTED FOR TUESDAY NIGHT AND WEDNESDAY WITH SURFACE AND UPPER RIDGING BUILDING IN. TEMPS WILL WARM TO THE LOW AND MID 40S FOR WED. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 343 AM EST MON NOV 11 2013 THE LONG TERM PERIOD WILL FEATURE TEMPERATURES MODERATING ABOVE NORMAL AS A SOUTHWEST FLOW ALOFT DEVELOPS AHEAD OF AN EVOLVING LONGWAVE TROUGH OVER THE WESTERN UNITED STATES. PREDOMINATELY DRY WEATHER WILL PREVAIL THROUGH SATURDAY AS A LARGE DRY SURFACE HIGH BECOMES PARKED OVER THE EASTERN HALF OF THE NATION. THERE IS A LOW CHANCE OF RAIN OR MIXED RAIN AND SNOW SHOWERS WITH THE PASSAGE OF A WEAK FRONTAL BOUNDARY THURSDAY NIGHT AND FRIDAY BUT ONLY VERY LIGHT PRECIP AMOUNTS EXPECTED DUE TO THE OVERALL LACK OF MOISTURE ALONG THE FRONT. A BIG NORTHWARD SURGE OF MOISTURE FROM THE GULF OF MEXICO GETS UNDERWAY SATURDAY NIGHT AND SUNDAY... SO INCREASING CHANCES FOR RAIN EXPECTED ALONG WITH MILD TEMPS IN THE 50S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 708 AM EST MON NOV 11 2013 VFR CONDITIONS WILL TREND QUICKLY TOWARD MVFR FROM NORTH TO SOUTH THIS MORNING AS RAIN DEVELOPS. THE RAIN WILL CHANGE OVER TO A 1-2 HOUR PERIOD OF SNOW WHICH MAY LOWER THE VSBYS INTO IFR CATEGORY FOR A BRIEF TIME THIS AFTERNOON BEFORE ENDING. ICING IN THE CLOUDS IS LIKELY TODAY AS THIS BAND OF RAIN AND SNOW MOVES THROUGH. FREEZING LEVELS DESCENDING FROM 4000-6000 FT AT 12Z... TO AROUND 2500 FT AT 15Z... TO 1000 FT OR LESS AFTER 18Z. CONDITIONS WILL RETURN TO VFR TONIGHT BEHIND THE COLD FRONT... ALTHOUGH LAKE EFFECT SNOW SHOWERS MAY RESULT IN PERIODS OF MVFR/IFR VSBYS ALONG THE LK MI SHORELINE INCLUDING MKG. SFC WINDS WILL INCREASE TO 12 TO 22 KTS FROM THE WEST THIS MORNING THEN SHIFT TO THE NORTH AND REMAIN RATHER STRONG/GUSTY THIS AFTERNOON BEHIND THE COLD FRONT. && .MARINE... ISSUED AT 831 AM EST MON NOV 11 2013 I UPDATED THE GRIDS TO SHOW GALES IN THE NEAR SHORE FORECAST THIS AFTERNOON AND TONIGHT. CURRENTLY (830 AM) ONLY ONE STATION NEAR GREEN BAY HAS GUSTS TO GALE FORCE BUT GIVEN THE STRENGHT OF THE COLD ADVECTION OVER A RELATIVELY WARM LAKE MICHIGAN (50 DEGREE) IT WOULD SEEM WE SHOULD SEE THE GALES THIS AFTERNOON AND THIS EVENING. && .HYDROLOGY... ISSUED AT 343 AM EST MON NOV 11 2013 NO ISSUES EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR MIZ038>040. LM...GALE WARNING UNTIL 8 AM EST TUESDAY FOR LMZ844>849. && $$ UPDATE...WDM SYNOPSIS...JK SHORT TERM...JK LONG TERM...MEADE AVIATION...MEADE HYDROLOGY...JK MARINE...WDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1115 AM EST MON NOV 11 2013 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 343 AM EST MON NOV 11 2013 MUCH COLDER AIR WILL BE PUSHING INTO THE REGION TODAY AS A COLD FRONT MOVES THROUGH. RAIN IS EXPECTED THIS MORNING...WHICH WILL CHANGE OVER TO SNOW FROM NORTH TO SOUTH THIS AFTERNOON. MOST AREAS WILL SEE LITTLE OR NO SNOW ACCUMULATION...BUT AREAS NEAR HIGHWAY 10 COULD SEE AN INCH OR TWO BY THIS AFTERNOON. TEMPERATURES WILL FALL THROUGH THE 30S THIS AFTERNOON AND INTO THE 20S TONIGHT. LAKE EFFECT SNOW WILL INCREASE INTO TONIGHT AND ADDITIONAL SNOW ACCUMULATIONS ARE LIKELY MAINLY WEST OF U.S. 131. ONE TO LOCALLY FOUR INCHES WILL BE POSSIBLE TONIGHT THROUGH NOON TUESDAY. QUIETER WEATHER IS EXPECTED BY MID WEEK AND TOWARD THE WEEKEND. TEMPERATES WILL WARM TO MAINLY 45 TO 50. && .UPDATE... ISSUED AT 11115 AM EST MON NOV 11 2013 SO FAR (11 AM) THE FORECAST IS ON TRACK. THE RAIN TO SNOW LINE IS JUST BEHIND THE COLD FRONT BUT THE BELOW FREEZING TEMPERATURES REMAIN NORTH OF ROUTE 10 YET. THE RAIN TO SNOW LINE IS NEAR ROUTE 20. I EXPECT THE THE MAIN AREA OF RAIN ASSOCIATED WITH RR QUAD OF TO CONTINUE PROGRESS SOUTH WITH TIME. THE BACK EDGE OF THE PRECIPITATION SHOULD BE MOVING SOUTH THROUGH THE CWA AFTER 2 PM AND REACH THE I-96 AREA BY 4 PM AND I-96 BY 6 PM. AS FOR THE SNOW...THE RAIN/SNOW LINE SHOULD REACH THE GRR AREA BETWEEN 2 PM AND 3 PM... SO MAYBE AN HOUR OR TWO OF WET SNOW BEFORE IT END. I DO NOT SEE MUCH ACCUMULATION OUTSIDE OUR ADVISORY AREA. UP THERE...SINCE UP TO 3 INCHES HAS ALREADY FALLEN... AND THERE SEEMS TO BE A LAKE ENHANCED AREA OF SNOW MOVING SOUTH OVER NORTHERN LOWER MICHIGAN...THEY COULD SEE ANOTHER 1 TO 2 INCHES BRINGING THE STORM TOTAL TO 5 INCHES. I MAY NEED SOME SORT OF LAKE EFFECT SNOW ADVISORY FOR VAN BUREN AND POSSIBLY EXTREME WESTERN ALLEGAN COUNTY AS LATE MODEL RUNS SUGGEST THE SNOW BAND MAY MOVE ON SHORE OVERNIGHT. ALSO THE SNOW BAND OFF LAKE SUPERIOR IS SHOWN BY SEVERAL HIGH RES MODELS TO REACH WELL INTO OUR NORTHERN CWA NEAR US-131 SO I MAY NEED AN ADVISORY UP THERE TOO FOR THE AFTERNOON FORECAST PACKAGE. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 343 AM EST MON NOV 11 2013 A COLD FRONT WAS PUSHING SOUTHEAST ACROSS THE GREEN BAY REGION EARLY THIS MORNING. IT WILL SLIDE ACROSS THE GRR CWA BETWEEN 12Z AND 18Z. TEMPS WILL BE WARM ENOUGH FOR ALL RAIN AHEAD OF THE FRONT...THEN AN HOUR OR TWO AFTER IT PASSES WE SHOULD WET BULB DOWN TO SWITCH OVER THE ALL SNOW. HAVE DECIDED TO POST A WINTER WEATHER ADVISORY FOR LAKE...OSCEOLA AND CLARE COUNTIES. SNOWFALL RATES LATER THIS MORNING INTO EARLY THIS AFTERNOON COULD PRODUCE SLUSHY/SNOW COVERED ROADS THERE...AND BEING THE FIRST SNOW...THERE WILL BE SOME IMPACTS TO ADVISORY DRIVERS. WILL RUN IT THROUGH 3 PM AS IT APPEARS THERE WILL BE A LULL BETWEEN THE END OF THE SYNOPTIC PCPN AND THE BEGINNING OF THE LAKE EFFECT THAT KICKS IN TONIGHT. SHALLOW MOISTURE PROFILES ARE INDICATED BEHIND THE FRONT EARLY THIS EVENING...THEN DEEPER MOISTURE ARRIVES AS A SHORT WAVE SWINGS THROUGH OVERNIGHT. THE LAKE EFFECT SHOULD BEGIN TO RAMP UP AFTER ABOUT 03Z AND SHOULD CONTINUE THE REST OF THE NIGHT AND INTO TUESDAY MORNING. THE MEAN FLOW IS 340-355 THROUGH THIS PERIOD...SO THIS FAVORS AREAS WEST OF U.S. 131. THERE SHOULD BE A DOMINATE BAND SET UP AND DEPENDING ON IT/S EXACT ORIENTATION SOME AREAS NEAR THE POINTS AND WESTERN ALLEGAN AND VAN BUREN COUNTIES COULD GET A DECENT SNOW. I HAVE ONE TO FOUR INCHES INDICATED FOR NOW. WILL NOT ISSUE ANY HEADLINES FOR THE LAKE EFFECT PORTION OF THIS EVENT AS IT SHOULD BE MAINLY TOWARD MIDNIGHT INTO THE OVERNIGHT HOURS AND WE HAVE TIME TO FINE TUNE THINGS. THE SNOWS WILL DIMINISH TUESDAY AFTERNOON AS THE SHORT WAVE PASSES AND THE MOISTURE BECOMES INCREASINGLY SHALLOW. QUIET WEATHER IS EXPECTED FOR TUESDAY NIGHT AND WEDNESDAY WITH SURFACE AND UPPER RIDGING BUILDING IN. TEMPS WILL WARM TO THE LOW AND MID 40S FOR WED. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 343 AM EST MON NOV 11 2013 THE LONG TERM PERIOD WILL FEATURE TEMPERATURES MODERATING ABOVE NORMAL AS A SOUTHWEST FLOW ALOFT DEVELOPS AHEAD OF AN EVOLVING LONGWAVE TROUGH OVER THE WESTERN UNITED STATES. PREDOMINATELY DRY WEATHER WILL PREVAIL THROUGH SATURDAY AS A LARGE DRY SURFACE HIGH BECOMES PARKED OVER THE EASTERN HALF OF THE NATION. THERE IS A LOW CHANCE OF RAIN OR MIXED RAIN AND SNOW SHOWERS WITH THE PASSAGE OF A WEAK FRONTAL BOUNDARY THURSDAY NIGHT AND FRIDAY BUT ONLY VERY LIGHT PRECIP AMOUNTS EXPECTED DUE TO THE OVERALL LACK OF MOISTURE ALONG THE FRONT. A BIG NORTHWARD SURGE OF MOISTURE FROM THE GULF OF MEXICO GETS UNDERWAY SATURDAY NIGHT AND SUNDAY... SO INCREASING CHANCES FOR RAIN EXPECTED ALONG WITH MILD TEMPS IN THE 50S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 708 AM EST MON NOV 11 2013 VFR CONDITIONS WILL TREND QUICKLY TOWARD MVFR FROM NORTH TO SOUTH THIS MORNING AS RAIN DEVELOPS. THE RAIN WILL CHANGE OVER TO A 1-2 HOUR PERIOD OF SNOW WHICH MAY LOWER THE VSBYS INTO IFR CATEGORY FOR A BRIEF TIME THIS AFTERNOON BEFORE ENDING. ICING IN THE CLOUDS IS LIKELY TODAY AS THIS BAND OF RAIN AND SNOW MOVES THROUGH. FREEZING LEVELS DESCENDING FROM 4000-6000 FT AT 12Z... TO AROUND 2500 FT AT 15Z... TO 1000 FT OR LESS AFTER 18Z. CONDITIONS WILL RETURN TO VFR TONIGHT BEHIND THE COLD FRONT... ALTHOUGH LAKE EFFECT SNOW SHOWERS MAY RESULT IN PERIODS OF MVFR/IFR VSBYS ALONG THE LK MI SHORELINE INCLUDING MKG. SFC WINDS WILL INCREASE TO 12 TO 22 KTS FROM THE WEST THIS MORNING THEN SHIFT TO THE NORTH AND REMAIN RATHER STRONG/GUSTY THIS AFTERNOON BEHIND THE COLD FRONT. && .MARINE... ISSUED AT 831 AM EST MON NOV 11 2013 I UPDATED THE GRIDS TO SHOW GALES IN THE NEAR SHORE FORECAST THIS AFTERNOON AND TONIGHT. CURRENTLY (830 AM) ONLY ONE STATION NEAR GREEN BAY HAS GUSTS TO GALE FORCE BUT GIVEN THE STRENGHT OF THE COLD ADVECTION OVER A RELATIVELY WARM LAKE MICHIGAN (50 DEGREE) IT WOULD SEEM WE SHOULD SEE THE GALES THIS AFTERNOON AND THIS EVENING. && .HYDROLOGY... ISSUED AT 343 AM EST MON NOV 11 2013 NO ISSUES EXPECTED. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR MIZ038>040. LM...GALE WARNING UNTIL 8 AM EST TUESDAY FOR LMZ844>849. && $$ UPDATE...WDM SYNOPSIS...JK SHORT TERM...JK LONG TERM...MEADE AVIATION...MEADE HYDROLOGY...JK MARINE...WDM
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1241 PM CST MON NOV 11 2013 .UPDATE... ISSUED AT 1235 PM CST MON NOV 11 2013 UPDATED THE FORECAST TO INDICATE FALLING TEMPERATURES THROUGHOUT THE AFTERNOON AND MAINTAIN ISOLATED FLURRIES FOR THE AFTERNOON. STRATUS SHOULD BREAK UP BY THIS EVENING WITH INCREASING SUBSIDENCE FROM BUILDING HIGH PRESSURE. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM CST MON NOV 11 2013 MAIN FORECAST CONCERNS WILL BE TEMPERATURES AND FOG EARLY THIS MORNING. SURFACE ANALYSIS SHOWS A COLD FRONT ACROSS CENTRAL NEBRASKA AT THIS TIME THAT HAS BEEN STEADILY MOVING TO THE SOUTH ACROSS NORTHERN NEBRASKA EARLY THIS MORNING. SATELLITE SHOWS SOME CLOUDS A WAYS BEHIND THE COLD FRONT. SURFACE OBSERVATIONS HAVE SOME SPOTTY FOG THAT HAS BEEN REDUCING VISIBILITIES TO LESS THAN A MILE AT TIMES. DEW POINTS ACROSS THE AREA ARE FAIRLY HIGH...IN THE UPPER 30S TO MID 40S. AS TEMPERATURES FALL OFF THE VISIBILITY DROPS IN FOG. EXPECT THAT WITH THE LIGHT WINDS AHEAD OF THE FRONT AND THE MOIST AIR THERE WILL BE SOME FOG ACROSS THE AREA EARLY THIS MORNING. AS THE COLD FRONT MOVES SOUTH THE WINDS WILL TURN TO THE NORTH AND START TO INCREASE. THIS SHOULD BRING AN END TO THE FOG THIS MORNING. THE MAIN QUESTION WILL BE HOW WIDESPREAD THE FOG WILL BE AND HOW LOW THE VISIBILITIES WILL DROP. THE HRRR AND SREF BOTH REDUCE VISIBILITIES TO LESS THAN A MILE. WILL START WITH THAT AND WATCH. THE COLD FRONT IS EXPECTED TO BE MOST...IF NOT ALL...OF THE WAY THROUGH THE FORECAST AREA BY SUNRISE THIS MORNING. BEHIND THIS COLD FRONT THERE IS VERY COLD AIR THAT WILL BE PUSHING INTO THE FORECAST AREA. TEMPERATURES ARE NOT LIKELY TO WARM VERY MUCH AT ALL TODAY AND WILL PROBABLY FALL THROUGHOUT THE DAY. CLOUDS WILL PUSH INTO THE FORECAST AREA DURING THE DAY. THERE IS A FAIRLY TIGHT PRESSURE GRADIENT BEHIND THE COLD FRONT AS WELL. WINDS ALOFT REMAIN MAINLY 10 TO 20 KNOTS SO THE WIND SHOULD BE BREEZY WITH 10 TO 20 MPH AND GUSTS TO AROUND 25 MPH OR SO. A COLD HIGH PRESSURE SYSTEM WILL BUILD INTO THE FORECAST AREA TONIGHT. WITH THIS THE WINDS WILL BE LIGHT...SKIES WILL CLEAR OUT AND TEMPERATURES WILL CONTINUE TO DROP THROUGH THE NIGHT. LOW TEMPERATURES IN THE MORNING WILL BE IN THE 5 TO 15 DEGREE RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 353 AM CST MON NOV 11 2013 A STRONG SURFACE HIGH PRESSURE SYSTEM WILL BE NEARLY CENTERED OVER THE FORECAST AREA TO START THE EXTENDED PERIODS...AND IS EXPECTED TO DRIFT SLOWLY SOUTHWEST DURING THE DAY TUESDAY. THEREFORE...WHILE WINDS WILL BE GENERALLY LIGHT AND SHIFTING OUT OF THE OF THE SOUTH DURING THE AFTERNOON HOURS...TEMPERATURES WILL BE ON THE COLD SIDE...AS THE HEART OF THE APPROACHING COLD AIRMASS WILL ENCOMPASS THE ENTIRE FORECAST AREA. AS A RESULT...EXPECTED HIGH TEMPERATURES TUESDAY TO STRUGGLE TO REACH THE MIDDLE 30S ACROSS THE ENTIRE AREA...OR ALMOST 20 DEGREES BELOW NORMAL. TEMPERATURES WILL CONTINUE TO BE THE FOCUS TUESDAY NIGHT...ALBEIT THE AIRMASS WILL HAVE MODIFIED SOME SINCE MONDAY NIGHT THANKS TO SOUTHWESTERLY RETURN FLOW...AND EXPECT TEMPERATURES TO BOTTOM OUT IN THE UPPER TEENS TO LOWER 20S...OR ABOUT 10 DEGREES BELOW NORMAL MID NOVEMBER LOWS. THEREAFTER...THE UPPER LEVEL PATTERN WILL BECOME MORE WESTERLY TO NORTHWESTERLY...WITH MULTIPLE WEAK UPPER LEVEL DISTURBANCES AND ASSOCIATED FRONTS TRAVERSING THE LOCAL AREA THROUGH NEXT WEEKEND. WHILE SOME VERY LIGHT PRECIPITATION CANNOT BE RULED OUT FOR TIME TO TIME...ESPECIALLY THURSDAY AND AGAIN SATURDAY THROUGH SUNDAY...NO SIGNIFICANT PRECIPITATION ACCUMULATIONS ARE EXPECTED AS THERE WILL BE LIMITED MOISTURE TO WORK WITH. THE MAIN PIECE OF GOOD NEWS IS THAT WITH THE MORE WESTERLY FLOW PATTERN...TEMPERATURES SHOULD MODIFY CLOSER TO...OR EVEN ABOVE...SEASONAL NORMS WEDNESDAY AFTERNOON ONWARD...AND ANY PRECIPITATION THAT DOES MANAGE TO FORM WILL BE IN THE FORM OF LIGHT RAIN OR EVEN JUST SPRINKLES. LATE IN THE UPCOMING WEEKEND AND JUST BEYOND...MODEL DISCREPANCY GROWS AND THE 00Z EC CONTINUES TO BRING A VERY STRONG ARCTIC FRONT ACROSS THE LOCAL AREA...WITH 850MB TEMPS DROPPING TO -16C ACROSS THE LOCAL AREA...WHILE THE GFS MAINTAINS A MUCH MILDER AIRMASS ACROSS THE LOCAL AREA...KEEPING THE COLDER AIRMASS FURTHER EAST. GIVEN THAT THE EC APPEARS TO BE AN OUTLIER AT THIS POINT...WITH THE UPPER LEVEL PATTERNS OF THE GFS ENSEMBLES...UKMET AND GEM LOOKING MORE SIMILAR TO THE GFS...PLENTY OF UNCERTAINTY REMAINS...SO WILL NEED TO CONTINUE TO MONITOR THIS TIME PERIOD AS A RETURN TO UNSEASONABLY COLD TEMPERATURES IS POSSIBLE JUST BEYOND THE CURRENT SCOPE OF THE EXTENDED FORECAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1137 AM CST MON NOV 11 2013 CEILINGS SHOULD GRADUALLY RISE BEFORE SCATTERING OUT TONIGHT WITH HIGH PRESSURE CREATING QUITE A BIT OF SUBSIDENCE. WIND SPEEDS OUT OF THE NORTH SHOULD ALSO DIMINISH AS THE SURFACE PRESSURE GRADIENT RELAXES AND HIGH PRESSURE BUILDS IN. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HEINLEIN SHORT TERM...JCB LONG TERM...SAR AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1200 PM CST MON NOV 11 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 353 AM CST MON NOV 11 2013 MAIN FORECAST CONCERNS WILL BE TEMPERATURES AND FOG EARLY THIS MORNING. SURFACE ANALYSIS SHOWS A COLD FRONT ACROSS CENTRAL NEBRASKA AT THIS TIME THAT HAS BEEN STEADILY MOVING TO THE SOUTH ACROSS NORTHERN NEBRASKA EARLY THIS MORNING. SATELLITE SHOWS SOME CLOUDS A WAYS BEHIND THE COLD FRONT. SURFACE OBSERVATIONS HAVE SOME SPOTTY FOG THAT HAS BEEN REDUCING VISIBILITIES TO LESS THAN A MILE AT TIMES. DEW POINTS ACROSS THE AREA ARE FAIRLY HIGH...IN THE UPPER 30S TO MID 40S. AS TEMPERATURES FALL OFF THE VISIBILITY DROPS IN FOG. EXPECT THAT WITH THE LIGHT WINDS AHEAD OF THE FRONT AND THE MOIST AIR THERE WILL BE SOME FOG ACROSS THE AREA EARLY THIS MORNING. AS THE COLD FRONT MOVES SOUTH THE WINDS WILL TURN TO THE NORTH AND START TO INCREASE. THIS SHOULD BRING AN END TO THE FOG THIS MORNING. THE MAIN QUESTION WILL BE HOW WIDESPREAD THE FOG WILL BE AND HOW LOW THE VISIBILITIES WILL DROP. THE HRRR AND SREF BOTH REDUCE VISIBILITIES TO LESS THAN A MILE. WILL START WITH THAT AND WATCH. THE COLD FRONT IS EXPECTED TO BE MOST...IF NOT ALL...OF THE WAY THROUGH THE FORECAST AREA BY SUNRISE THIS MORNING. BEHIND THIS COLD FRONT THERE IS VERY COLD AIR THAT WILL BE PUSHING INTO THE FORECAST AREA. TEMPERATURES ARE NOT LIKELY TO WARM VERY MUCH AT ALL TODAY AND WILL PROBABLY FALL THROUGHOUT THE DAY. CLOUDS WILL PUSH INTO THE FORECAST AREA DURING THE DAY. THERE IS A FAIRLY TIGHT PRESSURE GRADIENT BEHIND THE COLD FRONT AS WELL. WINDS ALOFT REMAIN MAINLY 10 TO 20 KNOTS SO THE WIND SHOULD BE BREEZY WITH 10 TO 20 MPH AND GUSTS TO AROUND 25 MPH OR SO. A COLD HIGH PRESSURE SYSTEM WILL BUILD INTO THE FORECAST AREA TONIGHT. WITH THIS THE WINDS WILL BE LIGHT...SKIES WILL CLEAR OUT AND TEMPERATURES WILL CONTINUE TO DROP THROUGH THE NIGHT. LOW TEMPERATURES IN THE MORNING WILL BE IN THE 5 TO 15 DEGREE RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 353 AM CST MON NOV 11 2013 A STRONG SURFACE HIGH PRESSURE SYSTEM WILL BE NEARLY CENTERED OVER THE FORECAST AREA TO START THE EXTENDED PERIODS...AND IS EXPECTED TO DRIFT SLOWLY SOUTHWEST DURING THE DAY TUESDAY. THEREFORE...WHILE WINDS WILL BE GENERALLY LIGHT AND SHIFTING OUT OF THE OF THE SOUTH DURING THE AFTERNOON HOURS...TEMPERATURES WILL BE ON THE COLD SIDE...AS THE HEART OF THE APPROACHING COLD AIRMASS WILL ENCOMPASS THE ENTIRE FORECAST AREA. AS A RESULT...EXPECTED HIGH TEMPERATURES TUESDAY TO STRUGGLE TO REACH THE MIDDLE 30S ACROSS THE ENTIRE AREA...OR ALMOST 20 DEGREES BELOW NORMAL. TEMPERATURES WILL CONTINUE TO BE THE FOCUS TUESDAY NIGHT...ALBEIT THE AIRMASS WILL HAVE MODIFIED SOME SINCE MONDAY NIGHT THANKS TO SOUTHWESTERLY RETURN FLOW...AND EXPECT TEMPERATURES TO BOTTOM OUT IN THE UPPER TEENS TO LOWER 20S...OR ABOUT 10 DEGREES BELOW NORMAL MID NOVEMBER LOWS. THEREAFTER...THE UPPER LEVEL PATTERN WILL BECOME MORE WESTERLY TO NORTHWESTERLY...WITH MULTIPLE WEAK UPPER LEVEL DISTURBANCES AND ASSOCIATED FRONTS TRAVERSING THE LOCAL AREA THROUGH NEXT WEEKEND. WHILE SOME VERY LIGHT PRECIPITATION CANNOT BE RULED OUT FOR TIME TO TIME...ESPECIALLY THURSDAY AND AGAIN SATURDAY THROUGH SUNDAY...NO SIGNIFICANT PRECIPITATION ACCUMULATIONS ARE EXPECTED AS THERE WILL BE LIMITED MOISTURE TO WORK WITH. THE MAIN PIECE OF GOOD NEWS IS THAT WITH THE MORE WESTERLY FLOW PATTERN...TEMPERATURES SHOULD MODIFY CLOSER TO...OR EVEN ABOVE...SEASONAL NORMS WEDNESDAY AFTERNOON ONWARD...AND ANY PRECIPITATION THAT DOES MANAGE TO FORM WILL BE IN THE FORM OF LIGHT RAIN OR EVEN JUST SPRINKLES. LATE IN THE UPCOMING WEEKEND AND JUST BEYOND...MODEL DISCREPANCY GROWS AND THE 00Z EC CONTINUES TO BRING A VERY STRONG ARCTIC FRONT ACROSS THE LOCAL AREA...WITH 850MB TEMPS DROPPING TO -16C ACROSS THE LOCAL AREA...WHILE THE GFS MAINTAINS A MUCH MILDER AIRMASS ACROSS THE LOCAL AREA...KEEPING THE COLDER AIRMASS FURTHER EAST. GIVEN THAT THE EC APPEARS TO BE AN OUTLIER AT THIS POINT...WITH THE UPPER LEVEL PATTERNS OF THE GFS ENSEMBLES...UKMET AND GEM LOOKING MORE SIMILAR TO THE GFS...PLENTY OF UNCERTAINTY REMAINS...SO WILL NEED TO CONTINUE TO MONITOR THIS TIME PERIOD AS A RETURN TO UNSEASONABLY COLD TEMPERATURES IS POSSIBLE JUST BEYOND THE CURRENT SCOPE OF THE EXTENDED FORECAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1137 AM CST MON NOV 11 2013 CEILINGS SHOULD GRADUALLY RISE BEFORE SCATTERING OUT TONIGHT WITH HIGH PRESSURE CREATING QUITE A BIT OF SUBSIDENCE. WIND SPEEDS OUT OF THE NORTH SHOULD ALSO DIMINISH AS THE SURFACE PRESSURE GRADIENT RELAXES AND HIGH PRESSURE BUILDS IN. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...SAR AVIATION...HEINLEIN
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
111 PM CST MON NOV 11 2013 .UPDATE... ISSUED AT 111 PM CST MON NOV 11 2013 LOW CLOUD STREAMERS HAVE COMBINED AND BECOME A BIT MORE CELLULAR IN NATURE PER LATEST VISIBLE SATELLITE IMAGERY...BUT STILL BLANKET MOST OF THE FORECAST AREA WITH OVERCAST CONDITIONS. MOST OF THE DEVILS LAKE BASIN REMAINS SUNNY...BUT INCREASED SKY GRIDS THE REST OF THE AFTERNOON FOR ALL OTHER AREAS. CLOUDS NOT LIKELY TO DISSIPATE AND/OR MOVE OUT OF THE REGION UNTIL LOW-LEVEL WINDS SHIFT OT THE WEST LATE THIS AFTERNOON AND EVENING AS HIGH PRESSURE PUSHES EAST. REST OF THE FORECAST IN GOOD SHAPE WITH NO OTHER CHANGES AT THIS TIME. UPDATE ISSUED AT 1017 AM CST MON NOV 11 2013 CHALLENGES FOR THE MORNING UPDATE INCLUDE CLOUD AND TEMPERATURE TRENDS. VISIBLE SATELLITE SHOWING TWO LARGE LOW CLOUD STREAMERS ACROSS EASTERN NORTH DAKOTA AND NORTHWEST MN ORIGINATING FROM LAKE MANITOBA AND LAKE WINNIPEG RESPECTIVELY. THE FAR WESTERN EDGE OF THE DEVILS LAKE BASIN IS MOSTLY SUNNY AND THERE IS A GREATER MIX OF SUN AND CLOUDS FROM WINNIPEG TO FERGUS FALLS IN-BETWEEN THE TWO STREAMERS. RAP 925 HPA RH SUGGESTS THESE CLOUDS WILL HOLD TOGETHER FOR MUCH OF THE DAY AND WITH PERSISTENT NORTH-NORTHWEST FLOW...DO NOT EXPECT MUCH EXPANSION IN THE EAST-WEST DIRECTION. AS SUBSIDENCE INCREASES WITH BUILDING SURFACE HIGH PRESSURE THROUGH THE DAY... EXPECT A VERY SLOW EROSION OF THE CLOUDS. INCREASED SKY COVER MOST AREAS IN THE GRIDS. GIVEN WEAK COLD AIR ADVECTION FOR MUCH OF THE DAY...TEMPERATURES WILL BE MORE DEPENDENT ON CLOUD COVER. A COLD DAY FOR SURE...BUT CLOUDS MAY KEEP TEMPERATURES FROM RISING MUCH ABOVE CURRENT VALUES. TWEAKED THE DIURNAL CURVE BASED ON LATEST OBSERVATIONS... BUT DO NOT THINK AFTERNOON HIGHS WILL TOP 20 DEGREES. REST OF THE FORECAST IN GOOD SHAPE WITH NO MAJOR CHANGES AT THIS TIME. UPDATE ISSUED AT 620 AM CST MON NOV 11 2013 NO CHANGES PLANNED FOR THIS UPDATE...WITH FORECAST ON TRACK. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 325 AM CST MON NOV 11 2013 THE MAIN CHALLENGE WILL BE TEMPS AND CLOUD TRENDS...WITH ARCTIC AIRMASS IN PLACE INITIALLY THEN A WARMING TREND. MODELS REMAIN IN VERY GOOD AGREEMENT...AND THE NAM SEEMS TO HAVE A BETTER HANDLE ON LOW LEVEL MOISTURE AND CLOUDS. FOR TODAY...EXPECT A COLD DAY WITH MOST AREAS NOT GETTING OUT OF THE TEENS. THERE WILL BE LINGERING CLOUDS MAINLY IN THE NORTH AND EAST...WITH SOME LAKE AFFECT SNOW SHOWERS DOWNWIND OF LAKE OF THE WOODS NEAR BAUDETTE DURING THE MORNING. THE FETCH IS A BIT TOO WESTERLY FOR MUCH OF ANY ACCUMULATION THOUGH...BUT SOMETHING TO MONITOR IF WINDS TURN A BIT MORE NORTHERLY. FOR TONIGHT...ARCTIC HIGH PRESSURE AROUND 1042MB WILL MOVE FROM NW TO SE THROUGH THE REGION. EXPECT A VERY COLD NIGHT...WITH SOME AREAS IN NE ND A FEW DEGREES BELOW ZERO AND AROUND ZERO IN GRAND FORKS. THE RECORD LOWS FOR TUE MORNING ARE -9 AT THE NWS IN GRAND FORKS...-5 AT GFK AND -7 FARGO. THEREFORE...LOWS WON/T FALL TO RECORD LEVELS...BUT -5 AT THE AIRPORT IN GFK COULD BE APPROACHED WITH A DUSTING OF SNOW ON THE GROUND. ON TUESDAY...AN UPPER LEVEL RIDGE WILL BUILD IN AND STRONG MID LEVEL WAA WILL BEGIN. TEMPS WILL WARM ABOUT 10-15 DEGREES FROM TODAYS HIGHS...WITH PLENTY OF SUNSHINE FOR MOST AREAS. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 325 AM CST MON NOV 11 2013 FOR WEDNESDAY...EVEN WARMER AIR AND WESTERLY SFC FLOW WILL MOVE INTO THE AREA. EXPECT TEMPS TO WARM INTO THE LOW/MID 40S FOR THE ENTIRE REGION. GIVEN THE FAVORABLE WEST SFC WINDS AND 850MB TEMPS WARMING TO AROUND +10C BY 18Z WED...SOME AREAS COULD EVEN APPROACH 50 WITH NO SNOW COVER TO SPEAK OF. FOR THURSDAY-SUNDAY...THE UPPER FLOW BECOMES A BIT MORE NORTHWESTERLY ON THURSDAY AS AN UPPER SHORTWAVE TROUGH SKIRTS THE CANADIAN BORDER. WINDS WILL SHIFT NORTHWEST BEHIND A WEAK COLD FRONT HELPING TO KNOCK TEMPS DOWN A BIT FROM WEDNESDAY. ALTHOUGH FORCING IS WEAK...A BIT OF VERY LIGHT PRECIP IS POSSIBLE. MODEL DIFFERENCES SIGNIFICANTLY INCREASE LATE IN THE WEEK INTO NEXT WEEKEND. WHILE AN UPPER TROUGH IS EXPECTED TO DEVELOP FROM THE ROCKIES INTO THE PLAINS...THE ECMWF HAS BEEN SLOWER AND MORE AMPLIFIED WITH ITS EVOLUTION THAN THE GFS OVER THE PAST FEW RUNS. THIS SOLUTION WOULD RESULT IN WELL ABOVE NORMAL TEMPS FOR MUCH OF NEXT WEEKEND BEFORE A STRONGER COLD SURGE AND BETTER PRECIP CHANCES ARRIVE. THE 00Z GFS...ON THE OTHER HAND...BRINGS THE COLD FRONT THROUGH ON SATURDAY...WITH GENERALLY SEASONABLE TEMPS. SIGNIFICANT SPREAD IS EVIDENT AMONG GFS ENSEMBLE MEMBERS DURING THIS TIME. THUS...FORECAST CONFIDENCE IS VERY LOW...AND WILL NOT DEVIATE MUCH FROM CONTINUITY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1017 AM CST MON NOV 11 2013 MVFR CIGS EMANATING FROM LAKE WINNIPEG STREAMING DOWN AND COVERING A REGION ESSENTIALLY BOUNDED BY KDVL TO THE WEST AND KBJI TO THE EAST. PLENTY OF COVER UPSTREAM TO KEEP MVFR IN PLACE THROUGH MID AFTERNOON. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...DK LONG TERM...DK/MAKOWSKI AVIATION...WJB
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1017 AM CST MON NOV 11 2013 .UPDATE... ISSUED AT 1017 AM CST MON NOV 11 2013 CHALLENGES FOR THE MORNING UPDATE INCLUDE CLOUD AND TEMPERATURE TRENDS. VISIBLE SATELLITE SHOWING TWO LARGE LOW CLOUD STREAMERS ACROSS EASTERN NORTH DAKOTA AND NORTHWEST MN ORIGINATING FROM LAKE MANITOBA AND LAKE WINNIPEG RESPECTIVELY. THE FAR WESTERN EDGE OF THE DEVILS LAKE BASIN IS MOSTLY SUNNY AND THERE IS A GREATER MIX OF SUN AND CLOUDS FROM WINNIPEG TO FERGUS FALLS IN-BETWEEN THE TWO STREAMERS. RAP 925 HPA RH SUGGESTS THESE CLOUDS WILL HOLD TOGETHER FOR MUCH OF THE DAY AND WITH PERSISTENT NORTH-NORTHWEST FLOW...DO NOT EXPECT MUCH EXPANSION IN THE EAST-WEST DIRECTION. AS SUBSIDENCE INCREASES WITH BUILDING SURFACE HIGH PRESSURE THROUGH THE DAY... EXPECT A VERY SLOW EROSION OF THE CLOUDS. INCREASED SKY COVER MOST AREAS IN THE GRIDS. GIVEN WEAK COLD AIR ADVECTION FOR MUCH OF THE DAY...TEMPERATURES WILL BE MORE DEPENDENT ON CLOUD COVER. A COLD DAY FOR SURE...BUT CLOUDS MAY KEEP TEMPERATURES FROM RISING MUCH ABOVE CURRENT VALUES. TWEAKED THE DIURNAL CURVE BASED ON LATEST OBSERVATIONS... BUT DO NOT THINK AFTERNOON HIGHS WILL TOP 20 DEGREES. REST OF THE FORECAST IN GOOD SHAPE WITH NO MAJOR CHANGES AT THIS TIME. UPDATE ISSUED AT 620 AM CST MON NOV 11 2013 NO CHANGES PLANNED FOR THIS UPDATE...WITH FORECAST ON TRACK. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 325 AM CST MON NOV 11 2013 THE MAIN CHALLENGE WILL BE TEMPS AND CLOUD TRENDS...WITH ARCTIC AIRMASS IN PLACE INITIALLY THEN A WARMING TREND. MODELS REMAIN IN VERY GOOD AGREEMENT...AND THE NAM SEEMS TO HAVE A BETTER HANDLE ON LOW LEVEL MOISTURE AND CLOUDS. FOR TODAY...EXPECT A COLD DAY WITH MOST AREAS NOT GETTING OUT OF THE TEENS. THERE WILL BE LINGERING CLOUDS MAINLY IN THE NORTH AND EAST...WITH SOME LAKE AFFECT SNOW SHOWERS DOWNWIND OF LAKE OF THE WOODS NEAR BAUDETTE DURING THE MORNING. THE FETCH IS A BIT TOO WESTERLY FOR MUCH OF ANY ACCUMULATION THOUGH...BUT SOMETHING TO MONITOR IF WINDS TURN A BIT MORE NORTHERLY. FOR TONIGHT...ARCTIC HIGH PRESSURE AROUND 1042MB WILL MOVE FROM NW TO SE THROUGH THE REGION. EXPECT A VERY COLD NIGHT...WITH SOME AREAS IN NE ND A FEW DEGREES BELOW ZERO AND AROUND ZERO IN GRAND FORKS. THE RECORD LOWS FOR TUE MORNING ARE -9 AT THE NWS IN GRAND FORKS...-5 AT GFK AND -7 FARGO. THEREFORE...LOWS WON/T FALL TO RECORD LEVELS...BUT -5 AT THE AIRPORT IN GFK COULD BE APPROACHED WITH A DUSTING OF SNOW ON THE GROUND. ON TUESDAY...AN UPPER LEVEL RIDGE WILL BUILD IN AND STRONG MID LEVEL WAA WILL BEGIN. TEMPS WILL WARM ABOUT 10-15 DEGREES FROM TODAYS HIGHS...WITH PLENTY OF SUNSHINE FOR MOST AREAS. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 325 AM CST MON NOV 11 2013 FOR WEDNESDAY...EVEN WARMER AIR AND WESTERLY SFC FLOW WILL MOVE INTO THE AREA. EXPECT TEMPS TO WARM INTO THE LOW/MID 40S FOR THE ENTIRE REGION. GIVEN THE FAVORABLE WEST SFC WINDS AND 850MB TEMPS WARMING TO AROUND +10C BY 18Z WED...SOME AREAS COULD EVEN APPROACH 50 WITH NO SNOW COVER TO SPEAK OF. FOR THURSDAY-SUNDAY...THE UPPER FLOW BECOMES A BIT MORE NORTHWESTERLY ON THURSDAY AS AN UPPER SHORTWAVE TROUGH SKIRTS THE CANADIAN BORDER. WINDS WILL SHIFT NORTHWEST BEHIND A WEAK COLD FRONT HELPING TO KNOCK TEMPS DOWN A BIT FROM WEDNESDAY. ALTHOUGH FORCING IS WEAK...A BIT OF VERY LIGHT PRECIP IS POSSIBLE. MODEL DIFFERENCES SIGNIFICANTLY INCREASE LATE IN THE WEEK INTO NEXT WEEKEND. WHILE AN UPPER TROUGH IS EXPECTED TO DEVELOP FROM THE ROCKIES INTO THE PLAINS...THE ECMWF HAS BEEN SLOWER AND MORE AMPLIFIED WITH ITS EVOLUTION THAN THE GFS OVER THE PAST FEW RUNS. THIS SOLUTION WOULD RESULT IN WELL ABOVE NORMAL TEMPS FOR MUCH OF NEXT WEEKEND BEFORE A STRONGER COLD SURGE AND BETTER PRECIP CHANCES ARRIVE. THE 00Z GFS...ON THE OTHER HAND...BRINGS THE COLD FRONT THROUGH ON SATURDAY...WITH GENERALLY SEASONABLE TEMPS. SIGNIFICANT SPREAD IS EVIDENT AMONG GFS ENSEMBLE MEMBERS DURING THIS TIME. THUS...FORECAST CONFIDENCE IS VERY LOW...AND WILL NOT DEVIATE MUCH FROM CONTINUITY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1017 AM CST MON NOV 11 2013 MVFR CIGS EMANATING FROM LAKE WINNIPEG STREAMING DOWN AND COVERING A REGION ESSENTIALLY BOUNDED BY KDVL TO THE WEST AND KBJI TO THE EAST. PLENTY OF COVER UPSTREAM TO KEEP MVFR IN PLACE THROUGH MID AFTERNOON. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...DK LONG TERM...DK/MAKOWSKI AVIATION...WJB
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 248 PM CST MON NOV 11 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY INDICATE THAT THE ARCTIC COLD FRONT HAS BLASTED INTO CENTRAL ILLINOIS AND INDIANA WHILE A POTENT 1043MB SURFACE HIGH IS NOSING SE ACROSS THE NORTHERN PLAINS. TRAILING EDGE OF A MID-LEVEL CLOUD DECK IS DROPPING SOUTH ACROSS CENTRAL AND EAST-CENTRAL WISCONSIN AND LOCATIONS IN THIS AREA ARE SEEING SOME SUNSHINE ARRIVE. MEANWHILE FARTHER NORTH...LAKE EFFECT STREAMERS ARE GROWING A LITTLE MORE SOLID THANKS TO MID-LEVEL MOISTURE MOVING SW ACROSS LAKE SUPERIOR. WIND TRAJECTORIES HAVE BECOME FAVORABLE FOR ACCUMULATING LAKE EFFECT SNOW SHOWERS...BUT THE DRY AIR HAS LIMITED THE INTENSITY TO ONLY LIGHT SNOW SHOWERS AND FLURRIES. AS THE ARCTIC HIGH MOVES TOWARDS THE REGION...SNOW SHOWERS AND TEMPS ARE THE MAIN FORECAST CONCERNS. TONIGHT...ARCTIC HIGH PRESSURE WILL BUILD ACROSS THE NORTHERN PLAINS TOWARDS THE WESTERN GREAT LAKES. 850MB TEMPS WILL DROP IN THE MID TEENS BELOW ZERO...BUT WILL STILL HAVE A DECENT PRESSURE GRADIENT TO KEEP NNW WINDS PERSISTENT THOUGH LESS GUSTY. WIND TRAJECTORIES AND LOWERING INVERSION HEIGHTS ARE FAVORABLE FOR LAKE EFFECT STRATO-CU TO BUILD SOUTH INTO CENTRAL WISCONSIN THIS EVENING...SIMILAR TO THE STRATUS BEHAVIOR OVER MINNESOTA THIS MORNING. MOISTURE MOVING SOUTH OUT OF ONTARIO ALSO SUPPORTS THIS IDEA. SO HAVE INCREASED CLOUD COVER AND PRECIP CHANCES ACROSS NORTHERN WISCONSIN FOR THE EVENING. STILL NOT EXPECTING MUCH ACCUMULATION THOUGH. THE MID-LEVEL MOISTURE WILL SHIFT TO THE EAST OVERNIGHT AS LOW LEVEL WINDS BACK AROUND SLIGHTLY. SHOULD THEREFORE SEE THE LAKE CLOUDS/STRATUS RETREAT TOWARDS THE SNOW BELTS OF N-C WISCONSIN LATE. BUT DESPITE CLEARING TAKING PLACE OVERNIGHT...THE BRISK NNW WINDS WILL KEEP TEMPERATURES UP AND WILL GO WITH LOWS RANGING FROM THE LOWER TEENS NORTH TO THE LOWER 20S SOUTH. TUESDAY...STRONG ARCTIC HIGH PRESSURE WILL SHIFT SOUTHEAST TOWARDS THE MID-MISSISSIPPI VALLEY. AS THIS OCCURS...LOW LEVEL WINDS WILL BACK TO THE NORTHWEST AND THEN THE WEST-NORTHWEST...WHICH WILL CAUSE MORNING LAKE EFFECT CLOUDS TO RETREAT NORTH TO THE UPPER PENINSULA. SHOULD OTHERWISE SEE A MOSTLY SUNNY TO PARTLY CLOUDY DAY ACROSS THE REGION. RATHER THIN MID AND HIGH CLOUDS WILL FILTER SOUTH AROUND MIDDAY WHICH WILL LIKELY PARTIALLY FILTER THE SUN. HIGHS WILL REMAIN COLD...WITH HIGHS RANGING FROM THE MIDDLE 20S NORTH TO LOWER 30S SOUTHEAST. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 248 PM CST MON NOV 11 2013 THE BRIEF COLD SNAP WILL END WEDNESDAY AS A FLAT UPPER RIDGE ARRIVES AND LOW LEVEL FLOW BECOMES SOUTHERLY. HE UPPER FLOW BECOMES SOUTHWEST THURSDAY THROUGH FRIDAY WITH A WEAK SURFACE FRONT FROM THE SOUTHERN PLAINS TO THE GREAT LAKES PROVIDING SOME SUPPORT FOR LIGHT PRECIPITATION THURSDAY AND FRIDAY. IT SHOULD BE MOSTLY RAIN THURSDAY AND THURSDAY NIGHT AND THEN CHANGE TO LIGHT SNOW FRIDAY AS THE FRONT EDGES EAST. THEN DRY AND MILD SATURDAY THROUGH AT LEAST SUNDAY MORNING AS UPPER HEIGHTS RISE AND SOUTHERLY FLOW INCREASES AT THE SURFACE. THE GFS AND ECMWF THEN BEGIN TO DIVERGE GREATLY FOR SUNDAY NIGHT THROUGH NEXT TUESDAY. THE GFS BRINGS A SHORTWAVE TROUGH THROUGH THE GREAT LAKES WITH TWO SURFACE LOWS IN THE PLAINS PHASING OVER NORTHERN ILLINOIS AND MOVING INTO MICHIGAN WITH RAIN SUNDAY AFTERNOON AND EVENING. THE ECMWF IS MUCH SLOWER AND DEEPER WITH THE APPROACHING TROUGH EVENTUALLY PRODUCING A CLOSED UPPER LOW OVER IOWA WHICH SLOWS AND DEEPENS MONDAY AND TUESDAY. IT WOULD BRING RAIN AND MILD WEATHER SUNDAY AND MONDAY AND THEN A SNOWSTORM MONDAY NIGHT THROUGH TUESDAY NIGHT. THAT/S TOO FAR OUT TO THINK ABOUT RIGHT NOW AND IT IS RATHER EARLY IN THE SEASON...BUT THESE TYPE OF SYSTEMS ARE THE ONES THAT PRODUCE SOME OF THE BIGGER SNOWS IN NORTHEAST WISCONSIN. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1131 AM CST MON NOV 11 2013 BAND OF PRECIPITATION ALONG AN ARCTIC COLD FRONT HAS SHIFTED INTO SOUTHERN WISCONSIN. ARCTIC AIRMASS IS FIRMLY ENTRENCHED ACROSS THE REGION. THOUGH IT IS VERY DRY...NNW WINDS WILL GENERATE LAKE EFFECT MVFR CLOUDS AND VSBYS IN OCCASIONAL SNOW SHOWERS OVER NORTH-CENTRAL WISCONSIN...INCLUDING RHINELANDER THROUGH TONIGHT. LOCALLY IFR VSBYS POSSIBLE WITHIN THE BEEFIER SNOW SHOWERS. SOME UNCERTAINTY HOW FAR SOUTH THE LAKE EFFECT CLOUDS WILL REACH. SOME INDICATIONS UPSTREAM THAT THEY COULD REACH INTO CENTRAL WISCONSIN TONIGHT...SO ADDED A TEMPO GROUP AT AUW/CWA TO ACCOUNT FOR THIS. IMPROVING CONDITIONS LATE TONIGHT INTO TUESDAY. LOW LEVEL WINDS WILL BACK AROUND TO THE WEST NORTHWEST...WHICH SHOULD CAUSE THE CLOUDS TO RETREAT TO THE NORTH. GUSTY NORTHWEST WINDS WILL SUBSIDE LATER TONIGHT AS WELL. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1131 AM CST MON NOV 11 2013 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 428 AM CST MON NOV 11 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY INDICATE STRONG COLD FRONT NOW EXTENDING ACROSS CWA FROM NEAR IMT TO RRL. BEHIND THE FRONT TEMPERATURES DROPPING QUICKLY INTO LOWER TO MIDDLE 20S. NORTHWEST WINDS ALSO QUITE GUSTY BEHIND FRONT. RADAR RETURNS HAVE FILLED IN/EXPANDED MIDNIGHT ONWARD IN RESPONSE TO STRONG FGEN FORCING OVER NORTHERN AND CENTRAL WI. LIGHT SNOW FALLING NORTH OF FRONT...RAIN SOUTH. NO SNOWFALL AMOUNTS REPORTED AS OF YET...THOUGH WEBCAMS FAR NORTH LOOK LIKE GOOD INCH HAS FALLEN SO FAR. MAIN CHANGE IN THIS FORECAST WAS TO SLOW PROGRESSION SLIGHTLY...INCLUDING RAIN TO SNOW CHANGEOVER. FORCING EXPECTED TO DROP SOUTH AND EAST THROUGH AREA THROUGH MID MORNING. HAVE TRIED TO DEPICT TEMP DROP THROUGH THIS MORNING...THEN NEAR STEADY TEMPS THROUGH THE AFTERNOON. WITH SLOWER DROP IN TEMPS OVER FOX VALLEY THIS MORNING...WILL UPDATE SPS SENT OUT EARLIER TO HIGHLIGHT AREAS WEST AND NORTH FOR THE MORNING COMMUTE. HIGH PRESSURE TO DROP SOUTH INTO THE PLAINS TONIGHT AND TUE MAKING CONDITIONS LESS FAVORABLE FOR LES OVER THE NORTH. HAVE STAYED WITH CHANCE/SCATTERED WORDING AND PREVIOUS SNOW AMOUNTS IN THE SNOW BELT FOR TODAY GIVEN DRY AIR AND LOWERING INVERSION HEIGHTS. COLD TEMPS TO CONTINUE THROUGH THE PERIOD WITH APPARENT TEMPS TODAY RUNNING IN THE SINGLE DIGITS NORTH AND TEENS SOUTH. TONIGHT WINDS WILL MAKE IT FEEL LIKE NEAR ZERO NORTH AND SINGLE DIGITS SOUTH. LIGHTER WINDS LATER TUE WILL BRING SOME IMPROVEMENT. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 428 AM CST MON NOV 11 2013 MDLS CONT TO INDICATE THE DEVELOPMENT OF UPR RDGS OVER THE ERN PACIFIC AND WRN ATLANTIC WITH A BROAD UPR TROF OVER THE CNTRL CONUS. MEAN FLOW OVER THE GREAT LAKES WL SWITCH FROM NW TO SW AS THIS UPR TROF DEVELOPS WHICH WL BRING MILDER...BUT MORE UNSETTLED WEATHER TO NE WI TOWARD NEXT WEEKEND. MAIN FCST ISSUE WL BE TRYING TO DETERMINE BEST PERIOD TO MENTION PCPN CHCS AS THE MDLS DIFFER ON WHICH BRANCH OF THE JET WL BECOME MORE DOMINANT. THE SFC RDG AXIS TO EXTEND FROM THE SRN PLAINS NEWD TO SRN SECTIONS OF THE GREAT LAKES TUE NGT. MEANWHILE...A WEAKENING UPR RDG WL BE PUSHING ACROSS THE UPR MS VALLEY TOWARD WI. THIS TRANSLATES TO A QUIET WEATHER PATTERN FOR NE WI UNDER MOSTLY CLR SKIES AND W-SW WINDS UNDER 10 MPH. WEAK WAA TO PERSIST THRU THE NGT AND THIS WL HELP TO COUNTER THE UNSEASONABLY COOL AIR MASS OVERHEAD. MIN TEMPS ARE EXPECTED TO BE CLOSE TO VALUES SEEN MON NGT (GENERALLY TEENS INLAND...AROUND 20 NEAR LAKE MI). INCREASING SW WINDS BETWEEN THE SFC HI OVER THE TN VALLEY AND A SFC LOW MOVING INTO WRN ONTARIO ON WED WL BRING A MILDER AIR MASS INTO WI. 8H TEMPS CONT TO RISE TO ALMOST +6C BY 00Z THU AND WITH SKIES STILL MOSTLY SUNNY...TEMPS WL BE ABLE TO RISE CLOSE TO SEASONAL NORMS (MID 30S TO AROUND 40 DEGS). SOME INCREASE IN CLOUDS CAN BE EXPECTED WED NGT AS A WEAK CDFNT PUSHES TOWARD THE WRN GREAT LAKES. NO PCPN IS FCST INITIALLY DUE TO THE VERY DRY AIR MASS OVER WI AT THE ONSET. PERSISTENT SW WINDS COMBINED WITH THE INCREASE IN CLOUDS...WL PREVENT TEMPS FROM FALLING AS FAR AS THE PAST TWO NGTS. LOOK FOR READINGS TO ONLY SETTLE INTO THE MID TO UPR 20S. THIS APPROACHING CDFNT IS PROGGED TO SLOW ITS FORWARD SPEED...WAITING FOR A TRAILING SHORTWAVE TROF (OVER THE UPR MS VALLEY) TO CATCH UP ON THU. AS THIS OCCURS...THE ATMOSPHERE WL CONT TO GRADUALLY SATURATE...AS WELL AS SEEING INCREASED LIFT FROM THE RIGHT ENTRANCE REGION OF THE UPR JET. CANNOT RULE OUT SOME LIGHT PCPN DEVELOPING SOMEWHERE OVER THE FCST AREA...ESPECIALLY DURING THE AFTERNOON. TEMPS SHOULD BE ABLE TO WARM ENUF SUCH THAT MOST OF THE PCPN WOULD FALL AS RAIN...ALTHO A MIX IS POSSIBLE ESPECIALLY IF THE PCPN CAN REACH NRN WI. THE WEAK CDFNT/SHORTWAVE TROF COMBINATION TO THEN PUSH ACROSS MOST OF WI THU NGT AND BRING AT LEAST A CHC OF PCPN TO THE ENTIRE FCST AREA. FCST ISSUE WL BE ON PCPN TYPE AS TEMPS DROP INTO THE UPR 20S TO LWR 30S AND THE 8H 0C ISOTHERM HOVERS OVER NE WI. SINCE THE BULK OF PCPN APPEARS TO MOVE THRU NE WI THU EVENING...ANTICIPATE PCPN TO FALL AS LIGHT SNOW NORTH AND A RAIN/SNOW MIX OVER CNTRL AND E-CNTRL WI. THIS SYSTEM IS FCST TO CLEAR THE REGION BY FRI...ALTHO THE LACK OF DRY AIR AND SUBSIDENCE BEHIND THE SYSTEM MAY KEEP MORE CLOUDS AROUND THRU THE DAY. DUE TO THE WEAK NATURE OF THE CDFNT AND WINDS ALOFT ONLY VEERING TO THE WEST...MAX TEMPS ON FRI ARE STILL EXPECTED TO BE NEAR NORMAL FOR MID-NOVEMBER. LARGE MDL DIFFERENCES REMAIN NEXT WEEKEND AS THE GFS/GEM FAVOR MORE OF A NRN STREAM SYSTEM IMPACTING NE WI SAT NGT INTO SUNDAY. ON THE OTHER HAND...THE ECMWF CONTS TO FOCUS ON A STRONGER SRN STREAM SYSTEM LIFTING N-NE FROM THE SRN PLAINS TO THE GREAT LAKES FROM SAT NGT INTO SUNDAY. WHILE THE THERMAL PROFILES WOULD INDICATE RAIN AS THE PRIMARY PCPN TYPE NO MATTER WHICH SOLUTION VERIFIES...THE ECMWF SOLUTION WOULD TAP MORE GULF MOISTURE AND THEREBY BRINGS HEAVIER RAINS TO NE WI. UNTIL THESE DIFFERENCES CAN BE BETTER RESOLVED... WL KEEP POPS IN THE CHC CATEGORY FOR BOTH SAT NGT AND SUNDAY WITH TEMPS ACTUALLY ABOVE NORMAL THRU THE WEEKEND. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1131 AM CST MON NOV 11 2013 BAND OF PRECIPITATION ALONG AN ARCTIC COLD FRONT HAS SHIFTED INTO SOUTHERN WISCONSIN. ARCTIC AIRMASS IS FIRMLY ENTRENCHED ACROSS THE REGION. THOUGH IT IS VERY DRY...NNW WINDS WILL GENERATE LAKE EFFECT MVFR CLOUDS AND VSBYS IN OCCASIONAL SNOW SHOWERS OVER NORTH-CENTRAL WISCONSIN...INCLUDING RHINELANDER THROUGH TONIGHT. LOCALLY IFR VSBYS POSSIBLE WITHIN THE BEEFIER SNOW SHOWERS. SOME UNCERTAINTY HOW FAR SOUTH THE LAKE EFFECT CLOUDS WILL REACH. SOME INDICATIONS UPSTREAM THAT THEY COULD REACH INTO CENTRAL WISCONSIN TONIGHT...SO ADDED A TEMPO GROUP AT AUW/CWA TO ACCOUNT FOR THIS. IMPROVING CONDITIONS LATE TONIGHT INTO TUESDAY. LOW LEVEL WINDS WILL BACK AROUND TO THE WEST NORTHWEST...WHICH SHOULD CAUSE THE CLOUDS TO RETREAT TO THE NORTH. GUSTY NORTHWEST WINDS WILL SUBSIDE LATER TONIGHT AS WELL. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....TE LONG TERM......KALLAS AVIATION.......MPC