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 161728
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
128 PM EDT THU APR 16 2015

.UPDATE...
ISSUED AT 657 AM EDT THU APR 16 2015

DECIDED TO PUT SPRINKLES INTO FORECAST OVER EASTERN CWA /ISQ-ERY/
MID MORNING INTO EARLY AFTN AS BAND OF SHOWERS OVER LOWER MICHIGAN
CONTINUES TO LIFT NORTHWARD. EVEN THOUGH SHRA WILL BE RUNNING INTO
THE DRY AIRMASS OVER AREA AS SEEN ON 00Z APX AND DTX RAOBS...THINK
ENOUGH FOCUS FM SHORTWAVE AND MOISTURE TRANSPORT AT H85-H7 IS GOING
TO END UP STRONG/PERSISTENT ENOUGH TO OUTWEIGH THE LOW-LEVEL DRY
AIR. VARIOUS HIGH RES MODELS AND THE 06Z/07Z HRRR REFLECTIVITY
OUTPUT POINT TO AT LEAST A BRIEF PERIOD OF LGT RAIN/SPRINKLES.
BEEFED UP SKY COVER SOME MORE AS WELL. OTHER THAN TWEAKS FOR VERY
SHORT TERM TEMP/DWPNT TRENDS...NO OTHER CHANGES WERE NEEDED TO
FORECAST.
&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT THU APR 16 2015

SHORTWAVE RIDGING PERSISTS TODAY BTWN NORTHERN STREAM SHORTWAVE THAT
CROSSES MANITOBA/NORTHERN ONTARIO AND CUTOFF LOW OVER FOUR CORNERS
OF SW CONUS. WEAK AREAS OF VORTICITY LIFTING INTO THE RIDGE BRINGING
A PUSH OF MID-LEVEL MOISTURE ADVECTION AROUND H7. DECENT AREA OF
SHRA IS LIFTING NORTHWARD OVER WESTERN LOWER MICHIGAN ON NORTH EDGE
OF MOISTURE TRANSPORT AT H85-H7 AND THIS COULD BRING VIRGA OR A FEW
SPRINKLES TO EASTERN CWA...POSSIBLY AS FAR WEST AS KESC PER HRRR
MODEL LATE MORNING INTO EARLY AFTN. ELSEWHERE WILL CERTAINLY BE MORE
CLOUDS THAN LAST COUPLE DAYS AS CIRRUS AND MORE PRONOUNCED AREA OF
AC/AS OVER MN SLIDES IN FOR THE AFTN. EVEN SO THOUGH...WARM START
SHOULD STILL ALLOW MAX TEMPS TO REACH WELL INTO THE 60S. RH VALUES A
BIT HIGHER THAN BONE DRY CONDITIONS SEEN TUE/WED WHERE RH BOTTOMED
OUT AROUND 10 PCT OVER INTERIOR WEST. FOR TODAY IN THOSE AREAS...
EXPECT MAINLY 18-25 PCT RANGE AT THE LOW-END. WINDS LESS THAN 10 MPH
MOST AREAS WITH LOCAL LAKE BREEZES CNTRL. OVERALL APPEARS TO NOT BE
AS MUCH OF ISSUE WITH FIRE WEATHER TODAY COMPARED TO TUE OR WED.

NORTHERN STREAM SHORTWAVE CROSSES NORTHERN ONTARIO TONIGHT WITH
TAIL OF ENHANCED CLOUD GRAZING CWA...ALONG WITH THE PASSAGE OF SFC
TROUGH...MORE OF A WIND SHIFT FM SW TO NW LATE TONIGHT. SINCE 1000-
700MB LAPSE RATES ARE HIGH...OVER 7C/KM BY LATE AFTN...AND FORCING
IS MOVING THROUGH WITH SUFFICIENT MOISTURE ALOFT...THINK THERE IS A
CHANCE OF SPRINKLES/VIRGA THIS EVENING AS THE FORCING MOVES
THROUGH...PERHAPS SIMILAR TO WHAT OCCURRED MON AFTN/EVENING. THAT
SAID...WINDS IN MIXED LAYER THIS EVENING DO INCREASE BY 03Z WITH 25-
30 KTS AT TOP PARTS OF THE MIXED LAYER. SO...FEASIBLE THAT GUSTY
WINDS COULD OCCUR IN THE VCNTY OF ANY WELL DEVELOPED CU OR
VIRGA/SPRINKLES. ALL FORCING IS OUT OF HERE BY MIDNIGHT AND SCT-BKN
CLOUDS SHOULD EXIT OVERNIGHT. SKIES WILL BE MAINLY CLEAR BY DAYBREAK
ON FRIDAY. LOWS TONIGHT SHOULD REMAIN ABOVE FREEZING ALL AREAS GIVEN
THE WINDS AND CLOUDS MOST OF THE NIGHT AND LACK OF COLD AIR BEHIND
THE TROUGH.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 436 PM EDT WED APR 15 2015

AFTER A QUIET AND GENERALLY WARM REST OF THIS WEEK...SIGNIFICANT
AMPLIFICATION OF THE FLOW IS EXPECTED THIS WEEKEND AND EARLY NEXT
WEEK AS A SHARP RIDGE BUILDS THRU WRN CANADA. THIS WILL FORCE A DEEP
TROF TO DEVELOP DOWNSTREAM WITH AXIS ROUGHLY OVER THE MISSISSIPPI
VALLEY BY MON. TYPICAL FOR THIS TIME OF YEAR...CLOSED LOWS
FREQUENTLY DEVELOP...AND THIS TROF WILL QUICKLY EVOLVE IN THAT
DIRECTION AS MAJORITY OF GUIDANCE INCLUDING GFS/GEM ENSEMBLES SHOW
EVOLUTION INTO A LARGE/COLD MID-LEVEL LOW OVER THE VICINITY OF THE
UPPER GREAT LAKES. MAY BE DIFFICULT TO DISLODGE THE LOW NEXT WEEK
ONCE IT DEVELOPS. SO...AFTER A WARM/DRY REST OF THIS WEEK...NEXT
WEEK WILL BE COLD AND GENERALLY UNSETTLED WITH PERIODIC CHANCES OF
SNOW AND RAIN SHOWERS. FROM A PCPN PERSPECTIVE...THE BIGGEST
CHALLENGE IS HOW THE SHARP PATTERN AMPLIFICATION INTERACTS WITH WHAT
IS CURRENTLY AN IMPRESSIVE LOOKING TROF CLOSING OFF OVER UT/CO.
MEDIUM RANGE GUIDANCE TODAY IS IN MUCH BETTER AGREEMENT IN SHOWING
THE AMPLIFICATION OF THE FLOW PICKING UP THE MID-LEVEL LOW AND
FORCING THE OPENED UP SYSTEM/REMNANT ENERGY NE INTO THE GREAT LAKES
REGION. RANGE OF POSSIBILITIES STILL INCLUDE A SIGNIFICANT RAIN
EVENT TO A RAIN CHANGING TO ACCUMULATING SNOW EVENT TO MINIMAL PCPN
IF THE SRN ENERGY DOES NOT LIFT FAR ENOUGH N AND W WITHIN THE
AMPLIFYING PATTERN. OPERATIONAL MEDIUM RANGE MODELS WEAKEN THE
ENERGY DRAMATICALLY AS IT LIFTS NE (WILL BE INTERESTING TO SEE IF
THAT ACTUALLY HAPPENS)...SO THE LOWEST PROBABILITY OUTCOME RIGHT NOW
IS ONE THAT BRINGS A SIGNIFICANT PCPN PRODUCING SYSTEM WITH A
PROMINENT DEFORMATION PCPN SHIELD INTO THE UPPER LAKES EARLY NEXT
WEEK. THAT SAID...THERE HAVE BEEN AND THERE STILL ARE SOME GFS/GEM
ENSEMBLES THAT DO SHOW SUCH A SCENARIO...SO IT CAN`T BE RULED OUT.

BEGINNING THU NIGHT...TAIL END OF SHORTWAVE TRACKING FROM HUDSON BAY
INTO QUEBEC WILL PASS ACROSS THE AREA THU NIGHT. FORCING FROM THE
RIGHT ENTRANCE OF AN UPPER JET STREAK AND MAIN DEEP LAYER QVECTOR
CONVERGENCE...WEAK AT THAT...PASS N OF THE AREA...SUPPORTING BEST
CHC OF -SHRA N OF HERE. ACROSS UPPER MI...VERY WEAK FORCING/WEAK
FRONTAL BOUNDARY AND WEAK MOISTURE TRANSPORT ALL SUGGEST PROSPECT OF
ANY PCPN IS VERY LIMITED AS SHORTWAVE PASSES. THUS...WILL RETAIN DRY
FCST FOR THU NIGHT.

IN THE MAIN FLOW TO THE N...ANOTHER SHORTWAVE IS FCST TO TRACK FROM
THE CANADIAN ROCKIES THU AFTN TO NRN ONTARIO FRI. MODELS HAVE
TRENDED TO MUCH BETTER AGREEMENT ON THIS WAVE WITH GEM/GFS/NAM
MOVING TO THE ECMWF SCENARIO WHICH HAS BEEN FARTHER N THAN THOSE
MODELS FOR SEVERAL RUNS. WITH THE TRACK OF THE SHORTWAVE JUST N OF
LAKE SUPERIOR...BEST FORCING AND POTENTIAL FOR PCPN WILL PASS BY TO
THE N. REMOVED SCHC POPS FROM INHERITED FCST IN FAVOR OF DRY
WEATHER. EXPECT HIGH TEMPS FRI IN THE 60S AWAY FROM LAKE MODERATION.
A FEW SPOTS MAY REACH 70F. INTERIOR RH SHOULD FALL TO 25-30PCT...
AND WINDS MAY BE A LITTLE GUSTY TO 15-20MPH AT TIMES...KEEPING FIRE
WX A CONCERN.

IN THE WAKE OF THE SHORTWAVE...HIGH PRES BUILDS INTO THE AREA FOR
SAT. WITH THE HIGH ENDING UP OVER LAKE SUPERIOR IN THE AFTN...IT
WILL BE A MUCH COOLER DAY NEAR LAKE SUPERIOR...ESPECIALLY FROM THE
KEWEENAW EASTWARD. RIGHT ALONG THE SHORE...TEMPS SHOULDN`T GET OUT
OF THE 30S. IN THE INTERIOR W HALF...TEMPS SHOULD RISE TO AROUND 60F
UNDER SUNNY SKIES.

SUN/MON...WILL CONTINUE TO UTILIZE A CONSENSUS APPROACH OF CURRENT
AND RECENT MEDIUM RANGE GUIDANCE FOR THE EVOLUTION OF THE SRN
ROCKIES ENERGY INTO THE GREAT LAKES AHEAD OF THE TROF AMPLIFICATION
OCCURRING INTO THE PLAINS/MISSISSIPPI VALLEY. IT APPEARS THERE MAY
END UP BEING TWO SURGES OF PCPN OR SFC LOW PRES WAVES...ONE
ASSOCIATED WITH LEAD ENERGY SWINGING UP FROM MEXICO AND A SECOND
ASSOCIATED WITH THE MAIN REMNANT OF THE ROCKIES MID LEVEL LOW.
LATEST GUIDANCE SUGGESTS RAIN WILL BEGIN SPREADING INTO UPPER MI SUN
AND THEN CONTINUE INTO MON. AIR MASS SHOULD COOL ENOUGH TO ALLOW
SOME SNOW TO BEGIN MIXING WITH THE RAIN OVER THE W ON MON. PTYPE
WILL THEN BECOME ALL SNOW ACROSS THE FCST AREA MON NIGHT FOR
WHATEVER PCPN LINGERS.

TUE/WED...LARGE/COLD MID-LEVEL LOW WILL HAVE DEVELOPED AND WILL BE
CENTERED IN THE VCNTY OF THE UPPER GREAT LAKES. COLD AIR
ALOFT/SPRING DAYTIME HEATING AND POTENTIAL OF SHORTWAVES ROTATING
THRU THE AREA WITHIN THE LARGE MID-LEVEL LOW CIRCULATION SUGGEST AT
LEAST SCT SHOWERY PCPN (MOSTLY SNOW BUT SOME RAIN AS WELL DURING
PEAK HEATING) BOTH DAYS WITH BEST COVERAGE IN THE AFTN INLAND FROM
LAKE SUPERIOR WHERE HEATING IS BEST. HIGH TEMPS BOTH DAYS SHOULD BE
IN THE MID 30S TO MID 40S...WARMEST SCNTRL.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 125 PM EDT THU APR 16 2015

VFR CONDITIONS WILL CONTINUE FOR THIS FORECAST PERIOD. IT IS
POSSIBLE THERE COULD BE A LIGHT SHOWER OR SPRINKLE AROUND EARLY THIS
EVENING AHEAD OF THE FRONT.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT THU APR 16 2015

NO WIDESPREAD GALES ARE EXPECTED THROUGH THE FORECAST PERIOD...BUT
THERE WILL BE A FEW PERIODS OF STRONGER WINDS STARTING THIS WEEKEND.
WINDS EXPECTED TO REMAIN AT OR BLO 20 KTS THROUGH FRIDAY NIGHT AS
PRESSURE GRADIENT IS WEAK. HIGH PRESSURE MOVING ACROSS ON SATURDAY
WITH LOW PRESSURE FOLLOWING OVER SCNTRL CANADA ON SUNDAY WILL RESULT
IN SETUP FOR STRONGER EAST-NORTHEAST WINDS TO 30 KTS OVER WESTERN LK
SUPERIOR SATURDAY AND SATURDAY NIGHT. STRONGEST WINDS WILL BE TOWARD
HEAD OF LK SUPERIOR NEAR DULUTH AND SUPERIOR. BY SUNDAY...AS THE LOW
PRESSURE SYSTEM APPROACHES...SOUTHEAST WINDS TO 30 KTS WILL BE
POSSIBLE OVER EASTERN HALF OF LK SUPERIOR WHILE WINDS DIMINISH IN
THE WEST. THE LOW CROSSES THE UPPER GREAT LAKES BY MONDAY WHILE
MERGING WITH ANOTHER LOW LIFTING IN FM THE CENTRAL PLAINS. EXPECT
WEST WINDS UP TO 30 KTS OVER MUCH OF THE LAKE LATER MONDAY INTO
TUESDAY IN WAKE OF THIS COMBINED LOW AS IT MOVES TO THE LOWER GREAT
LAKES.
&&

.HYDROLOGY...
ISSUED AT 332 PM EDT WED APR 15 2015

SEEMS THAT WITHOUT ANY SIGNIFICANT ADDITIONAL PRECIPITATION ADDED TO
THE ONGOING SNOWMELT...AT LEAST FOR THE REST OF THIS WEEK...MAINLY
LOOKING AT A FEW BANKFULL ISSUES ON SOME RIVERS WITH CONTINUATION OF
LOW-END ADVISORIES. BELOW NORMAL TEMPERATURES ARE EXPECTED MONDAY
THROUGH MUCH OF NEXT WEEK...WHICH WILL LIMIT MELTING OF ANY
REMAINING SNOW PACK AND REDUCE RIVER LEVELS.
&&

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

$$

UPDATE...JLA
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...TITUS
MARINE...JLA
HYDROLOGY...TITUS



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