RSS FeedsIssued by NWS Gaylord, MI
Versions: 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
000 FXUS63 KAPX 250517 AFDAPX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 1216 AM EST WED NOV 25 2009 .SYNOPSIS.../ISSUED AT 356 PM/ A MOIST LOW LEVEL AIR MASS WILL CONTINUE TO PRODUCE WIDESPREAD LOW CLOUDS ACROSS NORTHERN MICHIGAN THIS EVENING. AN AREA OF LOW PRESSURE WILL THEN LIFT INTO SOUTHERN LAKE MICHIGAN LATE TONIGHT AND PRODUCE A PERIOD OF RAIN INTO WEDNESDAY MORNING. THE RAIN WILL BECOME MORE SPOTTY WEDNESDAY AFTERNOON AND NIGHT...BEFORE ADDITIONAL RAIN SWEEPS ACROSS PORTIONS OF NORTHERN MICHIGAN THANKSGIVING DAY AND INTO THANKSGIVING NIGHT...POSSIBLY TURNING TO ALL SNOW ACROSS THE HIGHER TERRAIN OF NORTHERN LOWER MICHIGAN. JSL && .SHORT TERM.../ISSUED AT 938 PM/...TONIGHT 1007 MB LOW PRESSURE WAS OVER THE EASTERN IOWA/NORTHWESTERN ILLINOIS BORDER. APX AND SURROUNDING RADARS SHOW RAINFALL MOVING INTO SOUTHWEST LOWER MICHIGAN. THE MAIN SHORT TERM FORECAST CONCERN REVOLVES AROUND THE TIMING OF RAINFALL ARRIVAL. SURFACE LOW PRESSURE AND ASSOCIATED UPPER LEVEL SYSTEM WILL BEGIN TO EXERT ITS INFLUENCE OVER THE FORECAST AREA AFTER MIDNIGHT. RAIN WILL OVERSPREAD THE REGION FROM SOUTHWEST TO NORTHEAST. CURRENT GRIDS HAVE BEEN UPDATED TO PIN DOWN THE DETAILS BUT THE SPIRIT OF THE FORECAST REMAINS UNCHANGED. SULLIVAN && .LONG TERM.../ISSUED AT 356 PM/...WEDNESDAY AND BEYOND SHORT WAVE CROSSING THE MID MISSISSIPPI VALLEY THIS AFTERNOON...AND A TRAILING WAVE DIGGING SOUTHEAST THROUGH THE CANADIAN PRAIRIES... WILL BE THE MAIN FORECAST ISSUES THROUGH THE THANKSGIVING HOLIDAY. LEAD WAVE WILL CROSS THE LOWER GREAT LAKES WEDNESDAY...WHILE TRAILING SYSTEM CLOSES OFF OVER IOWA...THEN SLIDES EAST ACROSS LOWER MICHIGAN/INDIANA/OHIO THANKSGIVING DAY TOWARD A DATE WITH EAST COAST CYCLOGENESIS. PRECIPITATION EVOLUTION WITH THESE SYSTEMS THROUGH THURSDAY NIGHT WILL BE THE NEAR TERM FORECAST FOCUS...POSSIBLY WITH SOME SNOW ON THE BACK END OF THIS EVENT THURSDAY NIGHT. BEYOND THAT...ATTENTION THEN TURNS UPSTREAM WITH SPLIT FLOW TROUGHING MOVING INTO THE WESTERN STATES WHICH WILL IMPACT THE WEATHER OF THE UPPER LAKES HEADING INTO EARLY NEXT WEEK. WEDNESDAY...LEAD SHORT WAVE TROUGH FORECAST TO TRACK FROM SOUTHERN LAKE MICHIGAN/INDIANA...NORTHEAST ACROSS THE LOWER GREAT LAKES DURING THE DAY WEDNESDAY...WHILE TRAILING ENERGY DIVES ACROSS THE DAKOTAS AND INTO EASTERN IOWA BY WEDNESDAY NIGHT...THEN SWINGS EAST INTO INDIANA THANKSGIVING MORNING. 1007MB SURFACE LOW OVER SOUTHERN IOWA THIS AFTERNOON WILL DRIFT NORTHEAST AS ITS UPPER SUPPORT ACCELERATES AWAY TO THE NORTHEAST...ACROSS LAKE MICHIGAN AND UP TOWARD THE STRAITS BY THURSDAY MORNING. COLD LOW LEVEL AIR ASSOCIATED WITH TRAILING WAVE WILL ADVECT SOUTHEAST INTO THE OHIO VALLEY. DRY SLOTTING...ALREADY EVIDENT ACROSS ARKANSAS/ MISSOURI... EXPECTED TO PUNCH NORTHWARD ACROSS LOWER MICHIGAN WEDNESDAY MORNING ALONG WITH A PLUME OF STEEPER MID LEVEL LAPSE RATES (7-7.5C/KM 700-500MB). THIS WILL COMPLICATE PRECIP EVOLUTION A BIT WITH MORE WIDESPREAD RAIN PUSHING NORTH INTO THE UPPER PENINSULA...WITH A TENDENCY TOWARD MORE SHOWERY/CONVECTIVE PRECIPITATION ACROSS LOWER MICHIGAN WITH DECREASE IN STABILITY (POSSIBLY TAPERING OFF TO DRIZZLE WEDNESDAY EVENING AS DEEP LAYER QG DOWNWARD FORCING OVERSPREADS NORTHERN MICHIGAN). MEANWHILE...AS NEXT UPPER WAVE ARRIVES IN IOWA PRECIPITATION WILL BECOME BETTER ORGANIZED AROUND THAT FEATURE. ANOTHER PUSH OF DEEPER MOISTURE EXPECTED TO SURGE NORTHWARD INTO LOWER MICHIGAN OVERNIGHT ASSOCIATED WITH DEFORMATION AXIS AROUND NORTH SIDE OF THE CIRCULATION MOVING INTO INDIANA. WILL SIMPLY WORD THE FORECAST AS LIGHT RAIN AND DRIZZLE FOR ALL ZONES...THOUGH THE GREATER THREAT FOR ADDITIONAL MEASURABLE PRECIP LOOKS TO BE AFTER MIDNIGHT (LATER SHIFTS CAN ADD MORE TEMPORAL DETAIL IF NEEDED). THURSDAY...UPPER LEVEL TROUGH STARTING OUT ACROSS SOUTHERN LOWER MICHIGAN/INDIANA THANKSGIVING MORNING IS FORECAST TO MOVE GENERALLY EASTWARD DURING THE DAY AND GOING NEGATIVE TILT AS IT HEADS TOWARD THE EASTERN SEABOARD. SURFACE PRESSURE PATTERN OVER MICHIGAN WILL REMAIN GENERALLY "BAGGY" WITH STALLED/WEAKENING SURFACE LOW CONTINUING TO LANGUISH ACROSS THE STRAITS REGION/NORTHERN LAKE HURON. NEW ROUND OF STRONG QG FORCING AND LOW/MID LEVEL FRONTOGENESIS EXPECTED TO BRING MORE RAINFALL ESPECIALLY TO LOWER MICHIGAN CLOSER TO THE MAIN DYNAMICS. SOME DRY SLOTTING IN THE VICINITY OF SOUTHEAST LOWER...THIS COULD IMPACT PRECIPITATION IF IT DOES END UP PUSHING A BIT FARTHER WEST/NORTH INTO PARTS OF NORTHERN LOWER. BUT FOR NOW HIGH POPS APPEAR IN ORDER MOST AREAS FOR THANKSGIVING DAY. COLD AIR WILL BE CREEPING IN FROM THE NORTHWEST AND SOUTHWEST...THOUGH FORECAST THERMAL PROFILES STILL SUPPORT ALL RAIN THROUGH THANKSGIVING AFTERNOON. DEFORMATION AXIS AND DEEP MOISTURE WILL LINGER INTO THURSDAY NIGHT WITH FORCING SLOW TO EXIT THE FORECAST AREA. THIS IS WHERE PRECIP TYPE GETS TRICKY AS COLDER AIR CONTINUE TO PRESS INTO THE FORECAST AREA. EXPECT INITIAL CHANGEOVER ACROSS EASTERN UPPER AND HIGHER TERRAIN OF NORTHERN LOWER DURING THE EVENING...THEN A MIX OR MOSTLY SNOW CLOSER TO LAKE MICHIGAN. PRECIP MORE LIKELY TO REMAIN ALL RAIN CLOSER TO LAKE HURON. INITIAL QPF FORECAST WILL BE ON THE LIGHT SIDE...BUT ALWAYS HAVE TO BE WARY OF SLOW MOVING DEFORMATION ZONES AND THE POSSIBILITY OF SOME MESOSCALE NONSENSE FOCUSING SEVERAL INCHES OF SNOW ACROSS THE HIGHER TERRAIN OF NORTHERN LOWER THURSDAY NIGHT. FOR NOW WILL ADD SOME LIGHT ACCUMULATIONS ACROSS THE NORTHERN MICHIGAN HILLS. EXTENDED FORECAST (FRIDAY THROUGH TUESDAY)...FRIDAY STARTS OUT WITH OUR THANKSGIVING SYSTEM SHUFFLING OFF TO THE EAST...WITH SOME LINGERING SNOW POSSIBLE WITH ANY RESIDUAL MOISTURE LEFT BEHIND ACROSS THE STATE. STILL UNCERTAIN AS TO WHETHER WE`LL SEE ENOUGH COLD AIR/MOISTURE TO GENERATE LAKE EFFECT SNOW SHOWERS FRIDAY NIGHT...A LOT WILL DEPEND ON EVOLUTION/EXTENT OF CIRCULATION AROUND DEVELOPING EAST COAST LOW FRIDAY. 850MB TEMPERATURES AROUND -5C ARE POSSIBLE...BUT CBL DEPTH/MOISTURE IN QUESTION GIVEN POTENTIAL FOR LOW LEVEL ANTICYCLONIC FLOW TO BUILD IN FRIDAY NIGHT. SO WILL PASS ON DEALING WITH THESE MESOSCALE ISSUES AT THIS TIME FRAME AND KEEP FRIDAY NIGHT DRY (WITH A LITTLE MORE CLOUD COVER DOWNWIND OF THE LAKES)...AND A DRY SATURDAY STILL LOOKS GOOD WITH SHORT WAVE RIDGING ON THE DOORSTEP. ATTENTION THEN TURNS UPSTREAM FOR THE REST OF THE EXTENDED FORECAST WITH SPLIT FLOW TROUGHING SETTING UP ACROSS THE WESTERN U.S.. A LOT OF QUESTIONS WITH HOW THIS TROUGH WILL EVOLVE GIVEN POTENTIAL INTERACTIONS BETWEEN NORTHERN/SOUTHERN BRANCH ENERGY...AND POOR INTERNAL MODEL CONSISTENCY NOT HELPING (ESPECIALLY WITHIN GFS/GGEM RUNS). HEIGHT FALLS MOVING THROUGH THE MIDWEST AND TOWARD THE REGION DURING THE LATTER HALF OF THE WEEKEND SHOULD PUSH AN ELONGATED BAROCLINIC ZONE TOWARD THE UPPER GREAT LAKES. HOW QUICKLY THIS FEATURE MOVES AND WHETHER OR NOT ANY FRONTAL WAVES DEVELOP ALONG IT (SUCH AS IN THE 24/00Z ECMWF...NOT SOLD ON THIS IDEA YET) IS UNCERTAIN. QUICK PEEK AT THE NEWLY ARRIVING (AS I WRITE THIS PORTION OF THE DISCUSSION) 24/12Z GFS IS MUCH QUICKER/ MORE OPEN WITH SOUTHERN BRANCH ENERGY (ALSO NOT SURE ON THIS). AT THIS POINT...WILL CONCEDE THE POTENTIAL FOR SOME WARM ADVECTION PRECIPITATION AHEAD OF THE APPROACHING COLD FRONT DURING THE DAY SUNDAY...KEEP CHANCES FOR RAIN/SNOW IN FOR MONDAY...AND START TUESDAY OUT WITH A CHANCE OF RAIN AND BE PREPARED TO MAKE CHANGES AS WE GO FORWARD. DID NOT STRAY TOO FAR FROM CLIMATOLOGY WITH TEMPERATURES FOR THE MOST PART...TRENDED A BIT WARMER FOR SATURDAY AND A BIT COOLER FOR EARLY NEXT WEEK. PERHAPS A PATTERN SHIFTING TOWARD COLDER WEATHER LATER NEXT WEEK. JPB && .MARINE.../ISSUED AT 356 PM/ SURFACE LOW LIFTING UP ALONG THE WESTERN LOWER MICHIGAN SHORELINE WILL RESULT IN SHIFTING WINDS ACROSS THE NEARSHORE ZONES DURING WEDNESDAY. GUSTY EAST/SOUTHEAST WINDS CAN BE EXPECTED ACROSS NORTHERN LAKE HURON...WAVES COULD BECOME A BIT CHOPPY WITHIN THE STRAITS/FALSE DETOUR ZONE. WINDS ON NORTHERN LAKE MICHIGAN WILL SHIFT FROM SOUTHERLY TO WESTERLY WITH SURFACE LOW PASSAGE DURING THE AFTERNOON...THEN MORE NORTHWESTERLY OVERNIGHT. SURFACE LOW EXPECTED TO DRIFT ACROSS NORTHERN LAKE HURON/NORTH CHANNEL THANKSGIVING DAY...WHICH WILL PULL A STRONGER PRESSURE GRADIENT ACROSS THE LAKES AND ALLOW WINDS TO INCREASE ESPECIALLY GOING INTO THURSDAY NIGHT. IF THIS TREND HOLDS WILL LIKELY NEED SMALL CRAFT ADVISORIES WITHIN MOST NEARSHORE ZONES FROM THURSDAY AFTERNOON INTO FRIDAY WITH WINDS GUSTING IN THE 20-30KT RANGE. JPB && .AVIATION.../ISSUED AT 1230 AM/...VALID FOR 06Z TAFS LOW PRESSURE WILL APPROACH FROM OUR SOUTHWEST OVERNIGHT AND MOVE ACROSS NORTHERN MICHIGAN LATER TODAY INTO TONIGHT. CIGS/VSBYS WILL SLOWLY LOWER INTO THE IFR CATEGORY TONIGHT AT TVC AND CONTINUE INTO THIS EVENING. LIFR TO IFR CIGS AT PLN AND APN ARE EXPECTED TO CONTINUE THROUGH THE TAF PERIOD. OCCASIONAL RAIN AND DRIZZLE IS ANTICIPATED AT ALL TAF SITES OVER THE NEXT 24 HRS. AJS && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. LH...NONE. LS...NONE. && $$
