000
FXUS63 KAPX 041125
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
625 AM EST WED MAR 4 2015

.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 413 AM EST WED MAR 4 2015

...MORE COLD AIR TODAY WITH SNOW SHOWERS AND FLURRIES...

HIGH IMPACT WEATHER POTENTIAL: WIND CHILLS DIPPING INTO THE TEENS
BELOW ZERO EARLY THURSDAY MORNING.

PATTERN SYNOPSIS/FORECAST: MIDNIGHT SURFACE/COMPOSITE ANALYSIS SHOWS
A 989MB LOW OVER SOUTHERN JAMES BAY...TRAILING ARCTIC FRONT
SOUTHWEST INTO MICHIGAN/NORTHERN ILLINOIS/NORTHERN MISSOURI.
COLD/OCCLUDED FRONT EXTENDS FROM THE LOWER GREAT LAKES SOUTHWEST
ALONG THE OHIO RIVER INTO THE SOUTHERN PLAINS.  COLDER/DRIER AIR
FILTERING EASTWARD ACROSS THE MIDWEST/UPPER GREAT LAKES BEHIND THE
ARCTIC FRONT...WITH SUB-ZERO COLD INTO NORTHERN DAKOTA/NORTHERN
MINNESOTA/NORTHWEST ONTARIO.  170KT JET STREAK RUNS SOUTHWEST-
NORTHEAST RIGHT ACROSS LOWER MICHIGAN AHEAD OF AN ELONGATED SHORT
WAVE TROUGH/POTENTIAL VORTICITY ANOMALY SAGGING INTO THE UPPER
MIDWEST/NORTHERN PLAINS.  BROKEN AREA OF SNOW SHOWERS MOVING THROUGH
NORTHERN LOWER MICHIGAN EARLY ON ALONG/AHEAD OF THE ARCTIC
BOUNDARY...WITH SOME THIN CONVECTIVE STREAMERS IN THE COLDER AIR
UPSTREAM.

STRONG COLD ADVECTION EXPECTED TODAY IN THE WAKE OF THE PASSING
ARCTIC COLD FRONT...WHILE HEIGHT FALLS FROM UPSTREAM SHORT WAVE
TROUGH SPREAD ACROSS THE UPPER LAKES.  850MB TEMPERATURES SINK BACK
INTO FAMILIAR TERRITORY TODAY (SUB -20C) AS A SHARP/DEEP LAYER
THERMAL TROUGH PUSHES INTO WISCONSIN/UPPER MICHIGAN TONIGHT.

PRIMARY FORECAST CONCERNS: LAKE CONVECTION ISSUES. TEMPERATURE
TRENDS THROUGH TONIGHT.

TODAY...MAIN ISSUE TODAY IS DEALING WITH LAKE CONVECTION WITH
SHARPLY COOLING TEMPERATURES...IMPACT OF APPROACHING SHORT WAVE
TROUGH THIS AFTERNOON...AND A LOT OF ICE COVER OUT THERE. IMPACT OF
THE SHORT WAVE TROUGH IS INTERESTING...APPEARS OVERALL BACKGROUND
FORCING MAY END UP BEING FAIRLY MINIMAL (IMPACTS OF UPPER WAVE
LARGELY BEING OFFSET BY COLD ADVECTION/ISENTROPIC DOWNSLOPE FLOW).
BUT SOME UPTICK IN INVERSION HEIGHTS EXPECTED THIS AFTERNOON (TO THE
850-800MB VICINITY OFF BOTH LAKE SUPERIOR AND LAKE MICHIGAN).  BUT
THERE JUST ISN`T MUCH FETCH OUT THERE WITH WEST-NORTHWEST
TRAJECTORIES OFF EITHER LAKE...QUITE A BIT OF FAST ICE ON NORTHERN
LAKE MICHIGAN FROM THE ISLANDS EASTWARD TO THE LOWER PENINSULA...A
LITTLE MORE OPEN WATER WEST OF THE MANITOU ISLANDS SO WILL INITIALLY
FOCUS SNOW SHOWER CHANCES THIS MORNING AROUND TVC-CAD AND POINTS
WEST.  DIURNAL COMPONENT EXPECTED TO EXPAND CLOUD COVERAGE THIS
AFTERNOON...AS WELL AS COVERAGE OF SNOW SHOWERS/FLURRIES ACROSS
NORTHERN LOWER.  EXPECT SNOW SHOWER MORPHOLOGY TO TREND MORE
CELLULAR WITH TIME TODAY...SO NOT EXPECTING MUCH ACCUMULATION.
TEMPERATURES TODAY NOT LIKELY TO GO FAR...WILL CONTINUE TO FALL
THROUGH MID MORNING THROUGH THE TEENS AND PERHAPS EVEN INTO THE
SINGLE DIGITS...AND WITH STRONG COLD ADVECTION WILL PROBABLY NOT
RECOVER MUCH AS THE DAY PROGRESSES.

TONIGHT...LOW LEVEL WINDS EXPECTED TO VEER MORE NORTHWEST THIS
EVENING...AND BETTER SNOW SHOWER CHANCES SHOULD GRADUALLY "ROTATE"
WESTWARD TOWARD THE US-131 CORRIDOR AND WEST THIS EVENING INTO THE
OVERNIGHT.  LOSS OF DIURNAL HEATING COMPONENT SHOULD ALLOW SNOW
SHOWERS TO BECOME MORE ORGANIZED THIS EVENING...AND THINK A COUPLE
INCHES OF SNOW WEST OF US-131 IS NOT UNREASONABLE.  SOME SNOW
SHOWERS ALSO POSSIBLE OFF LAKE HURON CLIPPING PRESQUE ISLE/ALPENA
COUNTIES...OTHERWISE EXPECT CLOUDS TO DECREASE ELSEWHERE.  LOOKING
AT ANOTHER NIGHT OF SUB-ZERO TEMPERATURES ACROSS MOST OF THE
FORECAST AREA...THOUGH WINDS WILL BE SUBSIDING AS WELL SO DON`T
ANTICIPATE WIND CHILLS GETTING TOO OUT OF CONTROL AT THIS POINT.

&&

.SHORT TERM...(THURSDAY THROUGH FRIDAY NIGHT)
ISSUED AT 413 AM EST WED MAR 4 2015

...ARCTIC COLD SLOWLY MODERATING...

ARCTIC AIR WILL CONTINUE TO PLAGUE THE REGION THROUGH THE END OF THE
WEEK. MILDER AIR WILL EVENTUALLY MAKE A RUN AT DISLODGING THE
UNSEASONABLY COLD AIRMASS BUT IT WILL LIKELY BE AN ARDUOUS PROCESS.
THE BATTLE WILL RESULT IN SOME WIND...MAINLY FRIDAY AND BOUTS OF
SNOW SHOWERS FROM TIME TO TIME AS SHORT WAVES DROP DOWN THROUGH THE
FLOW...BEATING DOWN ANY IDEAS OF RIDGING THE ATMOSPHERE MAY HAVE AT
THE ONSET. HOWEVER...THERE WILL LIKELY BE BETTER CHANCES FOR THE
MILDER AIR TO WIN OUT (AT LEAST TEMPORARILY) BY THE MIDDLE PART OF
NEXT WEEK. IN THE MEANTIME...VERY COLD TEMPERATURES WILL CONTINUE
THURSDAY INTO THURSDAY MORNING WITH LOW WIND CHILLS ESPECIALLY LATER
THURSDAY NIGHT INTO FRIDAY MORNING. TEMPERATURES DO LOOK TO MODERATE
SOME FRIDAY AFTERNOON BUT GUSTY WINDS WILL MAKE IT HARD TO NOTICE
THE INCREASE IN TEMPERATURES. SO AFTER PERHAPS A FEW NORTHWEST FLOW
LAKE EFFECT SNOW SHOWERS THURSDAY MORNING..A BREAK IN THE
PRECIPITATION IS EXPECTED THURSDAY AFTERNOON INTO FRIDAY MORNING.
CHANCES FOR SNOW SHOWERS WILL THEN INCREASE FRIDAY AFTERNOON INTO
FRIDAY NIGHT. NOT A LOT OF SNOW ACCUMULATION EXPECTED WITH PERHAPS A
TOP END OF AN INCH OR TWO. HIGHS THURSDAY WILL STRUGGLE INTO THE
LOWER AND MIDDLE TEENS FOLLOWED BY HIGHS IN THE LOWER AND MIDDLE 20S
FRIDAY. LOWS IN THE SINGLE DIGITS ABOVE AND BELOW ZERO THURSDAY
NIGHT AND THE TEENS TO LOWER 20S FRIDAY NIGHT. IN ADDITION...THERE
WILL LIKELY BE LOW WIND CHILL TEMPERATURES ON THE ORDER OF 10 TO 20
BELOW ZERO THURSDAY NIGHT INTO EARLY FRIDAY DUE TO BRISK WINDS.

&&

.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 413 AM EST WED MAR 4 2015

...MORE TOLERABLE TEMPERATURES FOLLOWED BY MILDER READINGS...

THE PATTERN WILL ATTEMPT TO BREAK DOWN BY EARLY NEXT WEEK (AT LEAST
TEMPORARILY) AND LIKELY GRADUALLY MORPH INTO A ZONAL FLOW ALOFT. IN
THE MEANTIME...NORTHERN STREAM SHORT WAVES (CLIPPERS) WILL CONTINUE
TO MOVE THROUGH THE MAINLY NORTHWEST FLOW ALOFT OVER THE WEEKEND
RESULTING IN CHANCES FOR SNOW SHOWERS BUT WITH LITTLE APPRECIABLE
SNOW ACCUMULATION EXPECTED. A GRADUAL NORTHWARD SHIFT IN THE
BAROCLINIC ZONE WILL HOPEFULLY KEEP THESE SYSTEMS AT BAY EARLY NEXT
WEEK. TEMPERATURES ARE EXPECTED TO BE MORE TOLERABLE OVER THE
WEEKEND BEFORE MILDER READINGS LIKELY FINALLY ARRIVE BY THE MIDDLE
OF NEXT WEEK (HOPEFULLY FOR AT LEAST A COUPLE OF DAYS). I HAVE TO
ADMIT THAT THIS IS ALWAYS A RATHER TOUGH PATTERN TO PREDICT AS
MODIFIED ARCTIC AIR WILL LIKELY BE LURKING NOT TOO FAR OFF TO THE
NORTH. HIGHS OVER THE WEEKEND IN THE LOWER AND MIDDLE 30S...THE
MIDDLE TO UPPER 30S MONDAY THEN THE UPPER 30S TO MIDDLE 40S TUESDAY.
ALTHOUGH I AM NOT AS BULLISH ABOUT TEMPERATURES MAKING IT INTO THE
50S NEXT WEEK LIKE YESTERDAY (IT MAY HAVE BEEN WISHFUL THINKING...I
WOULD NOT TOTALLY RULE IT OUT JUST YET SO STAY TUNED. LOWS IN THE
UPPER SINGLE DIGITS AND TEENS ABOVE ZERO SATURDAY NIGHT...AND THE
MIDDLE TEENS TO MIDDLE 20S FOR BOTH SUNDAY AND MONDAY NIGHTS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 623 AM EST WED MAR 4 2015

LAKE CLOUDS AND SNOW SHOWERS/FLURRIES WILL PREDOMINATE
TODAY...BECOMING MORE OF AN ISSUE FOR TVC AND ESPECIALLY MBL
TONIGHT. VFR/HIGH END MVFR CONDITIONS EXPECTED FOR THE MOST
PART...SOME IFR VISIBILITIES IN SNOW SHOWERS AROUND TVC/MBL
POSSIBLE THIS AFTERNOON AND TONIGHT.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&

$$

NEAR TERM...JPB
SHORT TERM...SULLIVAN
LONG TERM...SULLIVAN