Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 KMQT 290735
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
335 AM EDT TUE JUL 29 2014

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 343 PM EDT MON JUL 28 2014

CURRENTLY THERE IS A DEEP UPPER LOW OVER NRN QUEBEC WITH A DEEP
TROUGH EXTENDING ACROSS MUCH OF THE ERN CONUS. OVER THE WRN CONUS
SITS AN AMPLIFIED RIDGE. AT THE SFC...THE CWA IS BETWEEN A 1027MB
HIGH THAT STRETCHES FROM THE CENTRAL PLAINS THROUGH SASKATCHEWAN AND
A 997MB LOW OVER NEW ENGLAND. A COUPLE PIECES OF ENERGY ROTATING
AROUND THE UPPER LOW ARE UPSTREAM OF THE CWA AND WILL IMPACT THE
AREA OVER THE NEXT 36 HOURS. THE FIRST IS JUST NNW OF LAKE SUPERIOR
AND IS PRODUCING SCATTERED SHOWERS JUST N OF LAKE SUPERIOR. THE
SECOND...WHICH IS STRONGER AND ASSOCIATED WITH A WEAK SFC
TROUGH...IS CURRENTLY OVER NRN ONTARIO AND W OF JAMES BAY.

THE FIRST SHORTWAVE WILL MOVE ACROSS THE WRN CWA THIS EVENING INTO
EARLY TONIGHT...BUT IS ONLY EXPECTED TO PRODUCE SOME ISOLATED TO
POSSIBLY SCATTERED SHOWERS AND THUNDERSTORMS. EXPECT LESS COVERAGE
OF PRECIP OVER THE CWA THAN IN CANADA DUE TO THE CWA BEING DOWNWIND
OF LAKE SUPERIOR AND SINCE THE SHORTWAVE ARRIVES AFTER PEAK
HEATING...BOTH OF WHICH WILL LEAD TO LESS INSTABILITY. BEST CHANCES
WILL BE OVER NWRN UPPER MI.

THE SECOND SHORTWAVE MOVES OVER THE CWA ON TUE...RESULTING IN STEEP
MID LEVEL LAPSE RATES. STILL APPEARS THAT CAPE VALUES WILL TOP OUT
AT 200-700J/KG AND WILL BE SKINNY. 0-6KM SHEAR LOOKS TO BE 20-25KTS
AND SHOULD BE UNIDIRECTIONAL. EXPECTATION IS TO AVOID SEVERE WEATHER
FOR THE MOST PART GIVEN LIMITED INSTABILITY AND WEAK SHEAR...BUT
COULD SEE A COUPLE OF MARGINALLY SEVERE HAIL STORMS AT BEST. BEST
INSTABILITY BEING OVER THE SCENTRAL PUTS THAT AREA UNDER THE BEST
POPS AND SHOULD BE THE LOCATION OF THE STRONGEST STORMS.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 334 AM EDT TUE JUL 29 2014

THE UPPER LEVEL LOW CENTERED NEAR JAMES BAY WILL PERSIST THROUGH
THE REST OF THE WORK WEEK...BEFORE GRADUALLY WEAKENING AND LIFTING
NORTHEAST THIS WEEKEND AND INTO EARLY NEXT WEEK. WITH A RIDGE OVER
THE WESTERN CONUS/CANADA...EXPECT THE FLOW ALOFT TO BE OUT OF THE
NORTHWESTERLY DIRECTION THROUGH THE LONG TERM PERIOD AND LEAD TO
TEMPERATURES BEING A LITTLE BELOW NORMAL. 850MB TEMPS WILL BE THE
COOLEST ON WEDNESDAY...AROUND 8C...BEFORE RISING TO AROUND 12C ON
THURSDAY AND REMAINING INTO THE WEEKEND. THUS...EXPECT WEDNESDAY TO
HAVE THE COOLEST HIGHS OF THE WORK WEEK (IN THE UPPER 60S AND LOWER
70S). WHILE HIGHS WILL BE A FEW DEGREES BELOW NORMAL ON WEDNESDAY
EXPECT A GRADUAL TREND TO NEAR NORMAL TEMPERATURES BY FRIDAY AND
CONTINUE INTO THE WEEKEND.

AS FOR PRECIPITATION...EXPECT GENERALLY DIURNAL SHOWERS OVER
INTERIOR LOCATIONS FOR WEDNESDAY THROUGH FRIDAY...ALTHOUGH THE
SEVERAL SHORTWAVES ROTATING AROUND THE UPPER LOW COULD LEAD TO A
COUPLE PERIODS OF SHOWERS DURING THE OVERNIGHT HOURS. ON
WEDNESDAY...THINK COVERAGE WILL BE FAIRLY LIMITED (AND OVER THE
SOUTH CENTRAL OR MAYBE EAST) AS THE MAIN SHORTWAVE ENERGY BRUSHES
THE NORTHEAST HALF OF THE CWA. DEEP MOISTURE APPEARS TO BE THE
MAIN LIMITING FACTOR BUT THERE IS A POCKET OF MOISTURE THAT
ROTATES THROUGH DURING THE DAY BETWEEN 800-700MB. THUS...WILL KEEP
POPS IN THE SLIGHT OR LOW CHANCE CATEGORY FOR MAINLY THE CENTRAL
AND EAST AWAY FROM THE STABILITY OF LAKE SUPERIOR. THERE ARE HINTS
OF A WEAK SHORTWAVE PRODUCING A FEW SHOWERS ON WEDNESDAY
NIGHT...BUT CONFIDENCE IS TOO LOW IN INCLUDE ANYTHING MORE THAN
SLIGHT CHANCE OF SHOWERS. THURSDAY SHOULD BE SIMILAR TO
WEDNESDAY...BUT WITH A LITTLE BETTER FOCUS OVER THE SOUTH CENTRAL
DUE TO THE POTENTIAL OF A STRONGER LAKE BREEZE OFF LAKE MICHIGAN.
WILL HAVE THE HIGHEST POPS ON FRIDAY (HIGH END CHANCES)...AS MODELS
CONTINUE TO INDICATE A STRONGER UPPER TROUGH ROTATING THROUGH DURING
THE DAY. IT APPEARS SUBSIDENCE BEHIND FRIDAY/S TROUGH SHOULD LEAD TO
A DRY SATURDAY. THUS...HAVE CONTINUE THE DOWNWARD TREND IN POPS.
PRECIP CHANCES WILL INCREASE ON SUNDAY AFTERNOON/NIGHT AS ANOTHER
SHORTWAVE DROPS SOUTHEAST ACROSS THE AREA. THIS WAVE MAY PROVIDE
SOME REAMPLIFICATION OF THE UPPER TROUGH AND CONTINUE PRECIPITATION
CHANCES INTO MONDAY.

FINALLY...FOR THUNDER POTENTIAL...MLCAPE VALUES ARE BELOW 500 J/KG
ON WEDNESDAY AFTERNOON AND WILL CAP AT SLIGHT CHANCES.
THURSDAY/FRIDAY HAVE MLCAPE VALUES A TOUCH HIGHER OVER THE SOUTH
CENTRAL...SO WILL HAVE CHANCES THERE AND SLIGHT ELSEWHERE WHERE
THERE ARE POPS IN THE AFTERNOON. FRIDAY WILL ALSO BE HELPED BY THE
SHORTWAVE...BUT WITH 0-6KM SHEAR VALUES STILL WEAK (15-20KTS) NOT
EXPECTING ANYTHING MORE THAN BRIEF HEAVY RAIN AND SOME SMALL HAIL IN
ANY OF THE STRONGER STORMS.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 140 AM EDT TUE JUL 29 2014

EXPECT SCT-BKN SHOWERS TO IMPACT MAINLY IWD AND CMX THIS MRNG IN
ADVANCE OF AN UPR DISTURANCE AND UNDER AXIS OF SOMEWHAT MOISTER/
MORE UNSTABLE AIR. ALTHOUGH VFR CONDITIONS WL PREDOMINATE...LOWER
VSBYS ARE PSBL UNDER SOME OF THE HEAVIER SHOWERS. SINCE RA HAS
FALLEN AT IWD AND CMX...SOME FOG MAY LOWER VSBYS THERE TOWARD
SUNRISE IF THERE IS ENUF CLRG AT THOSE SITES. ANOTHER ROUND OF
SHOWERS AND SOME TS WL IMPACT THE SITES LATER TODAY WITH THE APRCH
OF ANOTHER DISTURBANCE IN THE PRESENCE OF DAYTIME HEATING. THERE IS
TOO MUCH UNCERTAINTY ON TIMING/PLACEMENT OF TS TO INCLUDE AN
EXPLICIT MENTION OF TS ATTM. BEST SHOT AT KCMX WOULD BE MID MORNING
TO EARLY AFTN...WHILE IT WOULD BE SLIGHTLY LATER AT KIWD. ALTHOUGH
MVFR AND EVEN IFR CONDITIONS ARE PSBL UNDER SOME OF THE HEAVIER
SHOWERS...VFR CONDITIONS WL PREDOMINATE. DRYING/SUBSIDENCE IN THE
WAKE OF THIS DISTURBANCE WL END THE SHOWER THREAT LATE IN THE
AFTN/EVNG.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT
725 PM EDT MON JUL 28 2014

WITH A WEAK PRESSURE GRADIENT TYPICAL OF SUMMER DOMINATING THIS
FORECAST PERIOD...EXPECT WINDS UNDER 20 KTS THRU THE WEEK.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...TITUS
LONG TERM...SRF
AVIATION...KC/JLA
MARINE...KC





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.