Issued by NWS Marquette, 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
000 FXUS63 KMQT 300007 AFDMQT AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 415 PM EDT SAT AUG 29 2009 .SYNOPSIS... WATER VAPOR IMAGERY AND RUC SHOWING A CLOSED LOW OVER NORTHERN LAKE HURON EMBEDDED IN A LONGWAVE TROUGH OVER THE GREAT LAKES. A RIDGE IS OVER THE NORTHERN HIGH PLAINS AND THE WESTERN CANADIAN PRAIRIES. WEAK SHORTWAVE ENERGY WRAPPING AROUND THE LOW IS SWEEPING THROUGH THE FORECAST AREA. SURFACE LOW IS ALSO OVER NORTHERN LAKE HURON. DEEP MOISTURE WRAPPING AROUND THE LOW CONTINUE TO FEED SHOWERS AND LOW CEILING OVER THE FORECAST AREA. A LARGE SURFACE HIGH IS SETTLING IN OVER THE NORTHERN PLAINS BRINGING DRY STABLE AIR TO THE REGION. STRONG NORTH WINDS OVER LAKE SUPERIOR WILL CONTINUE TO PRODUCE HIGH WAVES OVER THE SOUTH SHORE OF LAKE SUPERIOR. THIS WILL PRODUCE WAVES UP TO 8 FEET AND DANGEROUSLY RIP CURRENTS. THUS CALLING FOR A HIGH RISK OF RIP CURRENTS...ESPECIALLY AROUND PICNIC ROCKS AREA. && .SHORT TERM...TONIGHT AND SUNDAY. THE CLOSED MIDLEVEL LOW WILL TRACK TO THE ONTARIO/QUEBEC BORDER BY 12Z SUNDAY AND INTO QUEBEC SUNDAY AFTERNOON. SUBSIDENCE AND PRONOUNCED DEEP LAYER DRYING INDICATE THE RAIN WILL END QUICKLY FROM WEST TO EAST TONIGHT. THE RAINS SHOULD LINGER A BIT LONGER OVER THE EAST AS IT WILL TAKE A LITTLE LONG FOR THE DRY AIR TO REACH THAT END OF THE FORECAST AREA. SOME UPPER 30S IN THE INTERIOR WEST WHERE CLOUDS SHOULD SCATTER OUT. SOME LOW CLOUDS WILL DEVELOP FOR A WHILE SUNDAY MORNING AND EARLY AFTERNOON AS DAYTIME HEATING WORKS ON LAKE MOISTURE...BUT EXPECT MOISTURE TO MIX OUT INTO THE DRIER AIR ALOFT...RESULTING IN INCREASING SUNSHINE AGAIN THROUGH LATE AFTERNOON. EVEN IN THE AREAS WHERE LAKE EFFECT CLOUDS LINGER SUNDAY MORNING. A NORTHERLY FLOW ILL KEEP THE DAY COOL...ESPECIALLY OVER THE NORTH CENTRAL NEAR LAKE SUPERIOR. TEMPERATURES REACH INTO THE LOW TO MID 60S. $$ .LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)... HIGH PRESSURE WILL BE OVERHEAD BY SUNDAY EVENING. WITH PWAT VALUES 40-50 PCT OF NORMAL COMBINED WITH LIGHT WINDS AND CLEAR SKIES...THE MAIN CONCERN WILL BE NEAR FREEZING OR BELOW FREEZING TEMPS FOR INLAND AREAS SUNDAY NIGHT/MONDAY MORNING. ALL SIGNS POINT TO A DECENT FROST SUNDAY NIGHT FOR AREAS WELL INLAND OF THE GREAT LAKES. THERE IS A SMALL CHANCE THAT THE W-SW WINDS MAY INCREASE SLIGHTLY LATE IN THE NIGHT AS THE HIGH MOVES SOUTH ALLOWING TEMPS TO STEADY OUT JUST ABOVE FREEZING...HOWEVER THIS SEEMS UNLIKELY. WILL THEREFORE GO WITH TEMPS JUST AT FREEZING ACROSS AREAS WELL INLAND FROM LAKE SUPERIOR ACROSS WESTERN MI. WILL HOLD OFF ON ANY FROST HEADLINES FOR NOW AS THERE IS A CHANCE THAT FREEZE HEADLINES OPPOSED TO FROST HEADLINES WILL BE NEEDED. WILL CONTINUE TO HIT FROST HARD IN THE FORECAST AND IN THE HWO. DRY AIR...CONTINUED SUBSIDENCE AND WARMING TEMPS AT 850MB SHOULD ALLOW FOR A VERY PLEASANT LAST DAY OF AUGUST. A WEAK WAVE MOVING WELL NORTHEAST OF THE REGION MAY ALLOW FOR SOME HIGH CLOUDS ACROSS THE AREA...OTHERWISE IT SHOULD BE MOSTLY SUNNY WITH TEMPS IN THE UPPER 60S AND LOWER 70S. ANOTHER COOL NIGHT ON MONDAY NIGHT...ALTHOUGH A LITTLE WARMER THAN SUN NIGHT. STILL MANY INLAND SPOTS WILL SEE TEMPS IN THE 30S AS THE SFC RIDGE WILL REMAIN IN CONTROL. EXPECT SUMMERLIKE WEATHER TO CONTINUE THROUGH NEXT SATURDAY...ALTHOUGH THE END OF THE WEEK HAS BECOME A LITTLE MORE CLOUDED WITH REGARDS TO PRECIPITATION CHANCES. THE 00Z GFS AND ECMWF BOTH SHOW A COLD FRONT MOVING INTO THE NORTHERN LAKES THURSDAY AS THE UPPER TROUGH OVER HUDSON BAY DEEPENS. THE GFS GENERALLY WANTS TO TAKE THIS FRONT THROUGH DRY...ALTHOUGH THE ECMWF SPINS UP A SYSTEM ALONG THE FRONT IN THE PLAINS AND MOVES IT TOWARD THE REGION THU-FRI...BRINGING PCPN WITH IT. THERE IS NOT MUCH RUN TO RUN CONTINUITY FROM THE ECMWF...AND THIS IS GENERALLY THE FIRST RUN THAT REALLY SHOWS PCPN. IN FACT...THE 12Z RUN AND ECMWF NOW SHOWS IT DRY ACROSS THE AREA UNTIL SATURDAY AT LEAST. WILL THEREFORE CONTINUE WITH A DRY FORECAST THROUGH THE EXTENDED...ALTHOUGH THE GFS AND GEFS SUGGEST SMALL POPS THU AFTN/NIGHT WITH FROPA. WILL ALSO GO DRY FOR THE REMAINDER OF THE EXTENDED FCST WITH SFC HIGH PRES NEARBY AND SLOW HEIGHT RISES. NO MAJOR FLUCTUATIONS IN TEMPS THROUGH THE EXTENDED. MAY SEE WARMER TEMPS WED/THU AHEAD OF THE FRONT...PERHAPS SLIGHTLY ABOVE NORMAL. A LITTLE COOLER AIRMASS BEHIND THE FRONT FRI-SAT...BUT STILL NEAR NORMAL. $$ .AVIATION /FOR THE 00Z TAF ISSUANCE/... VFR CONDITIONS RECENTLY REACHED AT BOTH TAF SITES AT THIS ISSUANCE. CIGS LIFT WAS RAPID AT CMX AND WILL PROGRESS A BIT MORE SLOWLY OVER THE FIRST 12 HRS AT SAW AS DEEP MOISTURE ALONG TROUGH ROTATES OUT. ALSO AT SAW...LLJ IN THE MORNING HOURS WILL MIX DOWN SOME GUSTY WINDS. NEAR END OF VALID PERIOD...HIGH RIDGE PRESSES IN FROM WEST. EXPECT WINDS TO BEGIN BACKING IN THE LAST 6 HOURS AT CMX AND NOT UNTIL CLOSER TO 00Z AT SAW. && .MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/... LOW PRESSURE OVER THE LOWER GREAT LAKES WILL SHIFT NORTH INTO QUEBEC ON SUNDAY MORNING. AS THE LOW MOVES TO NEW ENGLAND ON SUNDAY NIGHT...WINDS WILL DIMINISH BELOW 20 KNOTS. BY MONDAY HIGH PRESSURE WILL BUILD OVER THE GREAT LAKES. WITH THE CENTER OF THE HIGH REMAINING TO THE SOUTHEAST OF LAKE SUPERIOR...SOUTHWESTERLY WINDS OF 10 TO 20 KNOTS WILL PERSIST OVER THE LAKE THROUGH WEDNESDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN...LAKESHORE FLOOD ADVISORY FOR MIZ005 UNTIL MIDNIGHT TONIGHT. LAKE SUPERIOR...NONE. LAKE MICHIGAN...NONE. && SYNOPSIS/SHORT TERM...DLG LONG TERM...MRD AVIATION...SK MARINE...DLG
