Area Forecast Discussion
Issued by NWS Gaylord, MI

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000
FXUS63 KAPX 130355
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1155 PM EDT SAT APR 12 2014

.SYNOPSIS...
ISSUED AT 410 PM EDT SAT APR 12 2014

A SYSTEM ORGANIZING OVER THE PLAINS...WILL SLOWLY LIFT INTO THE
GREAT LAKES REGION TODAY. THIS PATTERN WILL GENERATE WIDESPREAD
RAIN...ALONG WITH A FEW THUNDERSTORMS...ACROSS NORTHERN MICHIGAN
THROUGH THE WEEKEND.

THE STORM SYSTEM WILL SLOWLY EXIT EAST OF THE REGION SUNDAY NIGHT.
COLDER AIR FILTERING INTO THE GREAT LAKES ON THE BACKSIDE OF THIS
EXITING SYSTEM...WILL GENERATE SNOW SHOWERS OVER NORTHERN MICHIGAN
SUNDAY NIGHT AND MONDAY.

A COUPLE OF SYSTEMS WILL REDEVELOP OVER THE PLAINS DURING THE
UPCOMING WORK WEEK...AND SWEEP ACROSS THE GREAT LAKES. THESE SYSTEMS
WILL GENERATE SOME SNOW SHOWERS ACROSS THE GREAT LAKES TUESDAY...ALONG
WITH MILDER TEMPERATURES AND RAIN SHOWERS THURSDAY.

&&

.UPDATE...
ISSUED AT 1017 PM EDT SAT APR 12 2014

A SOMEWHAT BUSY EVENING (THOUGH NOT AS MUCH SO AS DOWNSTATE).
SHRA/TSRA IN CENTRAL LOWER MI PRODUCED UP TO 1-2 INCHES OF RAIN
ALONG/SOUTH OF M-55. THIS ACTIVITY HAS BEEN PROPAGATING SOUTH INTO
THE UNSTABLE AIR THIS EVENING...AS IS TYPICAL. PRECIP COVERAGE WAS
VERY HEALTHY NEAR/SOUTH OF M-68 THIS EVENING...BUT A DECREASING
TREND IS NOTED OVER THE LAST HOUR. THIS WILL HOLD FOR THE NEXT 3-4
HOURS. HOWEVER...THE LOW-LEVEL COLD POOL NORTH OF THE WARM FRONT
DOWNSTATE IS PROGGED TO BECOME SHALLOWER OVERNIGHT...WITH 950MB
WINDS VEERING FROM SE TO SW. MEANWHILE...MID-LEVEL WINDS BACK AS A
SHALLOW 500MB RIDGE AXIS MOVES TO THE EASTERN LAKES...AND A TROF
EMERGES FROM THE SOUTHERN ROCKIES INTO THE HIGH PLAINS.

THIS MAY BE SUPPORTIVE OF ANOTHER NORTHWARD PUSH BACK INTO
NORTHERN LOWER MI IN THE LATE OVERNIGHT HOURS. UPSTREAM CONVECTIVE
TRENDS IN NE IOWA/SW WI ARE SUPPORTIVE OF A NORTHWARD PUSH. WILL
DIMINISH POPS SOMEWHAT AND MINOR OUT THUNDER WORDING FOR A
HOURS...BUT WILL RETURN HIGHER POPS/TSRA AGAIN LATE AS FAR NORTH AS
M-68.

NO CHANGES FOR EASTERN UPPER...WHICH SHOULD ESCAPE THE NIGHT WITH
SOME DRIZZLE/FOG/SPOTTY -RA.

&&

.SHORT TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 410 PM EDT SAT APR 12 2014

BROAD SFC LOW PRESSURE REMAINS ACROSS THE PLAINS THIS AFTERNOON WITH
A NEARLY STATIONARY FRONT STRETCHING EASTWARD THROUGH CHICAGO AND
INTO SRN LOWER MICHIGAN...FROM MUSKEGON TO THE THUMB. TALE OF TWO
HALVES OF THE STATE AS TEMPS SOUTH OF THE FRONT HAVE SOARED TO
AROUND 70 DEGREES...TEMPS TO THE NORTH RUNNING FROM THE MIDDLE 30S
TO MID 50S.

THERMAL GRADIENT OF COURSE RUNS ACROSS NRN MICHIGAN WITH AN
ASSOCIATED UPPER JET STREAK LIFTING UP INTO THE U.P. ASSOCIATED
F-GEN FORCING WITH THE FRONT HAS PRODUCED A NARROW CORRIDOR OF
PRECIP ALSO LIFTING UP THROUGH THAT AREA. MEANWHILE...BATCH OF
CONVECTION (MCS WANNABE) THAT DEVELOPED ALONG AND NORTH OF THE
FRONT IS ADVANCING INTO CENTRAL AND SOUTHERN LOWER MICHIGAN...FED
BY INCREASING S/SW FLOW ACROSS THE MIDWEST DRAGGING BROAD LOW
LEVEL THETA-E AXIS INTO LOWER MICHIGAN...AND OF COURSE STEEPER MID
LEVEL LAPSE RATES. THIN LINE OF TSTMS LINED UP FROM WISCONSIN
INTO LOWER MICHIGAN ALONG STRONGEST SURGE OF LOW LEVEL MOISTURE
AND LEADING EDGE OF REDUCED STABILITY ALOFT.

TONIGHT...PRECIP TO THE NORTH CONTINUES TO LIFT NORTH AS UPPER JET
STREAM LIFTS UP AND OUT OF THE REGION. MCS WANNABE WILL ADVANCE
EASTWARD THROUGH LOWER MICHIGAN OVER THE NEXT FEW HOURS AND BRING
CATEGORICAL RAINS TO AREAS ALONG AND SOUTH OF M-72. TOUGHER CALL
FOR NORTH OF M-72 AS BEST PRECIP MAY SKIRT BY TO THE SOUTH.
BUT...RECENT RADAR TRENDS SUGGEST PRECIP WILL EXPAND A BIT
NORTHWARD IN TIME AS EMBEDDED SMALL SCALE WAVE ON THE NRN FRINGE
OF THE PRECIP HAS BEEN LEADING THE MORE WIDESPREAD PRECIP A BIT
MORE NORTHWARD OVER THE LAST FEW HOURS. SO...WILL CONTINUE WITH
CATEGORICAL POPS HEADING INTO THE EVENING FOR THE ENTIRE CWA
ALTHOUGH RAINFALL AMOUNTS WILL BE ON THE VERY LIGHT SIDE FOR THE
NRN COUNTIES. SOME THUNDER MAY SNEAK INTO THE SRN TIER OF COUNTIES
EVENTUALLY AS REDUCED STABILITY ALOFT MAKES IT/S WAY NORTH.

THEN...WHAT HAPPENS NET IS A BIT UP IN THE AIR. SW-NE INVERTED
SFC TROUGH AXIS IS EXPECTED TO NOSE UP ACROSS NRN/CENTRAL LOWER
MICHIGAN TONIGHT. THIS SETS THE STAGE FOR ADDITIONAL ROUNDS OF
PRECIP TO DEVELOP ALONG THE TROUGH AXIS AND POTENTIALLY RUN UP
THROUGH NRN LOWER MICHIGAN TONIGHT. SO FAR...NOT MUCH GOING ON
UPSTREAM BUT IT IS GETTING A BIT BUBBLY BACK THROUGH IOWA AND
NEBRASKA...SIGNS THAT STUFF MAY GET GOING OVER THE NEXT FEW HOURS.

SO...WILL HANG ON TO THE CATEGORICAL RAIN IDEA FOR NRN LOWER
MICHIGAN THROUGH THE NIGHT AND SKIP ON ANY TIMING DETAILS FOR NOW.
PRECIP SHOULD DIMINISH IN EASTERN UPPER MICHIGAN THIS EVENING AS
NARROW CORRIDOR OF PRECIP LIFTS UP AND OUT. BUT SATURATING LOW
LEVELS WELL INTO THE COLDER AIR IS A GREAT SETUP UP FOR SOME
DRIZZLE/FOG UP THAT WAY.

THUNDER...AXIS OF STEEPER MID LEVEL LAPSE RATES EDGES INTO LOWER
MICHIGAN THIS EVENING ALTHOUGH BETTER LAPSE RATES HANG DOWN THROUGH
THE LOWER LAKES. BUT BROAD AREA OF NEGATIVE SHOWALTER INDICES DOES
EDGE UP THROUGH NRN LOWER MICHIGAN TONIGHT...SUGGESTING THE RISK
FOR SOME ELEVATED THUNDER. NO SEVERE WEATHER...BUT THUNDER MENTION
CURRENTLY IN THE HAZARDOUS WEATHER OUTLOOK LOOKS FINE.

.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 410 PM EDT SAT APR 12 2014

LOTS OF FUN TO BE HAD THROUGH THE FORECAST PERIOD...WITH THE MAJOR
ISSUES OF COURSE REVOLVING AROUND HEAVY RAIN POTENTIAL AS WELL AS
THE POSSIBILITY FOR SOME SNEAKY HEAVY SNOW IN SPOTS...NOT TO MENTION
WHAT IS LOOKING INCREASINGLY LIKE A TRULY COLD SHOT OF AIR THROUGH A
GOOD CHUNK OF NEXT WORK WEEK. THANKFULLY...THERE AREN`T A WHOLE LOT
OF ADDITIONAL PROBLEMS OR LARGER STORM SYSTEMS FORESEEN FROM MIDWEEK
ONWARD...THOUGH OF COURSE THERE`S ALWAYS A LITTLE SOMETHING TO LOOK
AT. THE BASIC SETUP THROUGH MONDAY WILL CONSIST OF A DEEPENING
NORTHERN STREAM TROUGH SLOWLY MEANDERING EASTWARD THROUGH THE
PLAINS...HELPING SUSTAIN PERSISTENT SOUTHERLY FLOW AND A WIDE OPEN
GULF MOISTURE TAP...FEEDING INTO A STRENGTHENING FRONTAL BOUNDARY
DRAPED SOMEWHERE FROM NORTHERN MICHIGAN DOWN THROUGH THE SOUTHERN
PLAINS. THAT SETUP IS A CLASSIC ONE FOR HEAVY RAIN SOMEWHERE ACROSS
THE REGION...AND INDEED THAT APPEARS RATHER LIKELY...THOUGH
PLACEMENT AND AMOUNTS REMAIN PROBLEMATIC AT BEST.

STILL LOOKING LIKE WE MAY SEE A BRIEF BREAK IN THE ACTION SUNDAY
MORNING AS NOCTURNAL LOW LEVEL JET FORCING UP AND OVER THE ELEVATED
WARM FRONT WANES...WHILE THE PASSAGE OF AN INITIAL SOUTHERN STREAM
WAVE BRINGS A BRIEF PERIOD OF DOWNWARD FORCING. MAY END UP SEEING A
LITTLE DRIZZLE AS LOW LEVEL SATURATION REMAINS NEAR THE STALLED
BOUNDARY. HOWEVER...APPROACH OF ANOTHER WEAK UPPER WAVE COMBINED
WITH ANOTHER UPTICK IN LOW/MID LEVEL WARM ADVECTION ASCENT AND A
TIGHTENING AXIS OF FRONTOGENESIS BASICALLY LAID OVER THE CWA SHOULD
HAVE LITTLE TROUBLE RE-IGNITING A LARGE AREA OF RAIN INTO THE
AFTERNOON/EVENING. IN FACT...THE FGEN SIGNAL IS DOWNRIGHT IMPRESSIVE
BY SUNDAY EVENING...WITH A SHARPLY SLOPED AXIS FROM THE SURFACE
RIGHT ON UP THROUGH 400MB...SUGGESTIVE OF WHAT SHOULD BE AN INTENSE
PERIOD OF UPWARD ASCENT. THAT WHOLE PROCESS WILL BE ENHANCED BY A
RATHER IMPRESSIVE AXIS OF UPPER JET FORCING SLIDING DIRECTLY
OVERHEAD - A FEATURE THAT HAS BEEN VERY PERSISTENT IN THE MODEL
GUIDANCE FOR SEVERAL DAYS NOW.

COMBINE THAT WITH PRECIP WATER VALUES NEARING 1.4 INCHES (UP NEAR
RECORD LEVELS PER KAPX CLIMATOLOGY) AND THE STAGE IS SET FOR WHAT
SHOULD BE A PERIOD OF RATHER PERSISTENT AND HEAVY RAIN. PLACEMENT IS
KEY FOR FLOODING POTENTIAL...BUT BASED ON TRENDS AND THE BASIC
SETUP...BELIEVE THE HEAVIEST RAIN AXIS WILL ESSENTIALLY BISECT THE
CWA...WHERE UPPER FORCING IS MAXIMIZED IN THE POST-FRONTAL
ENVIRONMENT. NOT SEEING MUCH IN THE WAY OF CONVECTIVE POTENTIAL AS
ALL OF THE INSTABILITY RESIDES ACROSS SOUTHERN MICHIGAN...THOUGH
WOULDN`T BE SURPRISED TO SEE SOME EMBEDDED THUNDER SUNDAY EVENING AS
THE AXIS OF STRONGEST FGEN BRIEFLY BISECTS AN AXIS OF LOWER
900-700MB THETA-E LAPSE RATES...PARTICULARLY DOWN TOWARD THE M-55
CORRIDOR. TEMPS ON SUNDAY ARE ALL BUT IMPOSSIBLE AS READINGS MAY
WELL BE STUCK IN THE 30S NORTH...ESPECIALLY AS THE FRONTAL BOUNDARY
SLOWLY SLIPS SOUTHWARD THROUGH THE DAY...PERHAPS WARMING AS HIGH AS
THE LOW 60S FAR SOUTHEAST AHEAD OF THE FRONT.

THE FORECAST CHALLENGE CONTINUES SUNDAY NIGHT INTO MONDAY THE MEAN
UPPER TROUGH SLOWLY SLIDES EAST...HELPING PUNT THE LOW LEVEL FRONT
SOUTHEASTWARD AND DRAGGING INCREASINGLY COLDER AIR INTO MUCH OF THE
AREA. PER MULTI-DAY TRENDS...THERE ARE STILL SOME BIG HINTS THAT A
NARROW CORRIDOR OF HEAVY SNOW MAY FALL OVER PORTIONS OF THE WESTERN
CWA...WHERE SUFFICIENT COLD AIR LOOKS TO ARRIVE BETWEEN ROUGHLY
09-13Z TO PUSH THE ENTIRE COLUMN BELOW 0C. THIS WHOLE SCENARIO
REMAINS VERY LOW CONFIDENCE...BUT WITH PERSISTENT UPPER JET FORCING
HOLDING FIRM THROUGH MIDDAY MONDAY...HAVE TO BELIEVE THERE WILL
STILL BE AN ELONGATED AXIS OF PRECIP ONGOING AS THE COLD AIR CRASHES
IN. PLACEMENT OF SAID PRECIP SHIELD WILL PLAY A BIG ROLE...AS AT THE
MOMENT...IT APPEARS THE LEAST AMOUNT OF PRECIP WILL OCCUR WHERE THE
COLDEST AIR ARRIVES FIRST - EASTERN UPPER. THE MAIN AREA OF FOCUS
WILL BE NORTHWEST LOWER WHERE ENOUGH COLD AIR CATCHES UP IN TIME TO
QUICKLY TURN ANY REMAINING PRECIP OVER TO SNOW. NOT LOOKING FOR A
VERY LONG PERIOD OF SNOW...BUT MAY SEE SOME INTENSE RATES FOR A FEW
HOURS. SREF GUIDANCE HAS BEEN ALL OVER THE PLACE WITH PROBABILITY
PLACEMENT (OWING TO UNCERTAINTIES IN THERMAL FIELDS)...BUT IT IS
INTERESTING TO SEE SOME LOW CHANCES FOR 8+ INCHES SHOWING UP
RECENTLY. AT THE MOMENT...GUT FEELING IS FOR MORE OF A 3-5" VERY WET
SNOW WHERE THE COLD/PRECIP CAN OVERLAP THE BEST...HIGHEST LIKELY
INTO THE HIGHER TERRAIN WHERE THINGS WILL BE A DEGREE OR TWO COLDER.
ACCUMULATION MAY TAKE A LITTLE WHILE TO GET UNDERWAY GIVEN THE SOGGY
PRECEDING CONDITIONS...BUT INTENSE RATES SHOULD OVERCOME THAT FOR A
TIME. PLENTY OF ROOM FOR THINGS TO CHANGE...BUT CURRENTLY LOOKING
LIKE A HEADLINE EVENT FOR A SLIVER OF COUNTIES.

AFTER THAT...THINGS LOOK TO GRADUALLY DRY OUT AND TURN DOWNRIGHT
COLD LATER MONDAY INTO TUESDAY...AS DEEP THERMAL TROUGHING SLIDES
OVERHEAD. WILL HAVE TO WATCH THE SNEAKY POSSIBILITY FOR ONE MORE
ROUND OF SNOW TO OVERTAKE THE AREA MONDAY EVENING/NIGHT AS THE MAIN
UPPER TROUGH AND ENTRANCE REGION JET FORCING SLIDES OVER THE AREA.
GUIDANCE TRENDS RECENTLY SUPPORT THIS NOTION SO SOMETHING TO WATCH.
OTHERWISE...VERY COLD H8 TEMPS AVERAGING -14 TO -16C SHOULD BE
ENOUGH TO SUPPORT SOME LAKE EFFECT INTO TUESDAY ON A MEAN
NORTH/NORTHWEST FLOW REGIME...WITH QUITE WINDY CONDITIONS EXPECTED
AS WELL. TEMPS MAY WELL STRUGGLE TO GET OUT OF THE 20S IN MANY SPOTS
AND WILL LOWER GOING READINGS SEVERAL DEGREES AS IT`S JUST DOWNRIGHT
COLD UPSTAIRS. HIGH PRESSURE WORKING OVERHEAD TUESDAY NIGHT SHOULD
SUPPORT SOME CHILLY OVERNIGHT LOWS...BUT A LITTLE WORRIED SOME
THICKER MID CLOUDS MAY ACT TO HOLD OFF ANY TRULY COLD READINGS.
STILL SOMETHING TO WATCH AS IT`S NOT OUT OF THE QUESTION SOME SPOTS
COULD DIP INTO THE SINGLE DIGITS WITH ANY FRESH SNOW COVER.

ANOTHER SNEAKY WEATHER SYSTEM MAY COME INTO PLAY LATER WEDNESDAY AS
WARM AIR STARTS TO FLOOD BACK NORTH...WITH HINTS FOR A FEW DAYS OF
AN ENHANCED BAND OF FRONTOGENESIS STRETCHING OUT SOMEWHERE NEARBY...
THOUGH THE EXACT PLACEMENT IS A BIG QUESTION MARK. THEREAFTER...
LOOKING FAIRLY QUIET THROUGH LATE WEEK AND EARLY NEXT WEEKEND AS
HEIGHT FALLS TAKE SHAPE TO THE WEST...SENDING BROAD SOUTHWEST FLOW
BACK INTO THE GREAT LAKES. LOTS OF QUESTIONS ABOUT WHERE AN UPSTREAM
FRONTAL BOUNDARY WILL BE LOCATED...WITH THE GFS BY FAR THE MOST
IMPACTFUL FOR THIS AREA. GIVEN THE UNCERTAINTY...AND PLENTY TO DEAL
WITH IN THE SHORT TERM...WILL PUNT WITH A DRY FORECAST FOR NOW AND
SEE WHERE FUTURE TRENDS TAKE US.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1155 PM EDT SAT APR 12 2014

WIDE RANGING CONDITIONS...BUT MVFR TO IFR MOST COMMON.

STALLING WARM FRONT WILL CONTINUE TO HOVER ACROSS CENTRAL/SOUTHERN
LOWER MI...UNTIL STRONG LOW PRESSURE LIFTS INTO LOWER MI SUNDAY
EVENING. MBL HAS MANAGED TO ESCAPE THE LOW CIGS FOR A BIT...BUT
SHRA/TSRA WILL RETURN TO THAT AREA OVERNIGHT. MVFR TO IFR
CONDITIONS WILL THEN PREVAIL ACROSS THE AREA...SEE TAFS FOR
DETAILS. PERIODS OF SHRA/PERHAPS TSRA OVERNIGHT INTO EARLY SUNDAY
MORNING...THEN HEAVY RAIN RETURNS SUNDAY EVENING.

EASTERLY WINDS TONIGHT WILL BECOMING NORTHERLY SUNDAY.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...FLOOD WATCH FROM 8 AM EDT SUNDAY THROUGH MONDAY EVENING FOR
     MIZ016>036-041-042.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

UPDATE...JZ
SYNOPSIS...TL
SHORT TERM...ADAM
LONG TERM...LAWRENCE
AVIATION...JZ







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