Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 250704
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
304 AM EDT MON MAY 25 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM EDT MON MAY 25 2015

NAM HAS A CLOSED 500 MB LOW AND TROUGH MOVING INTO THE NORTHERN
PLAINS THIS MORNING WITH A RIDGE OVER THE ERN U.S. POKING INTO THE
UPPER GREAT LAKES. THERE IS ALSO A STRONG SHORTWAVE OVER MISSOURI
THAT WILL HEAD NORTH TODAY AND MOVE THROUGH THE UPPER GREAT LAKES
THIS AFTERNOON.

NAM BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE AND DEEPER
MOISTURE THROUGH THE CWA TODAY BEFORE THE Q-VECTOR CONVERGENCE MOVES
OUT TONIGHT...BUT THE DEEPER MOISTURE REMAINS OVER THE AREA.
GFS...ECMWF AND CANADIAN SHOW ABOUT THE SAME THING AND WILL DO A
BLEND OF THEIR FORECASTS WHICH FOR THE MOST PART DID NOT CHANGE MUCH
FROM THE GOING FORECAST. DID BUMP UP WINDS THIS AFTERNOON AS THERE
IS A HINT OF STRONGER SOUTHWEST WINDS ACROSS THE SOUTHERN CWA AS A
SFC LOW MOVES ACROSS WESTERN LAKE SUPERIOR. WITH THE SFC LOW MOVING
A BIT FURTHER WEST...HEAVIER PCPN WILL BE FOCUSED MORE TO THE NORTH
AND WEST OF NORTHERN AND WESTERN U.P. WITH LIGHTER AMOUNTS ACROSS
THE SOUTH AND CENTRAL AND CUT QPF AMOUNTS THERE A BIT.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 304 AM EDT MON MAY 25 2015

SLIGHT CHANCES OF RAIN TUE MORNING WILL GIVE WAY TO INCREASED RAIN
CHANCES IN THE AFTERNOON/EVENING AND INTO TUE NIGHT AS SHORTWAVE
ENERGY MOVES THROUGH THE REGION. STILL THE USUAL MODEL UNCERTAINTY
WITH SHORTWAVE ENERGY THAT WILL BE MODIFIED BY CONVECTION...BUT THE
OVERALL SIGNAL IS GENERALLY AGREED ON. DEPENDING ON DETAILS THAT
WILL HAVE TO BE SORTED OUT LATER...ANYWHERE FROM 300 TO 1000 J/KG OF
CAPE MAY BE REALIZED TUE AFTERNOON/EVENING...SO THUNDER WILL REMAIN
IN THE FORECAST. STRONGER THUNDERSTORMS CAN NOT BE RULED OUT...BUT
GIVEN UNCERTAINTY WILL NOT PLAY THAT UP TOO MUCH YET.

AN UPPER WAVE MOVING THROUGH ON WED WILL INTERACT WITH ANY
INSTABILITY DURING PEAK HEATING. THE QUESTION REMAINS (WITH PLENTY
OF UNCERTAINTY) OF HOW MUCH INSTABILITY WILL RESULT. MODEL RANGE OF
CAPE VALUES IS CURRENTLY BETWEEN A COUPLE HUNDRED J/KG AND WELL OVER
1000 J/KG...SO WILL CERTAINLY NEED TO CONTINUE TO WATCH THE
SITUATION CLOSELY. DO THINK THAT PRECIP POTENTIAL IS LOWER THAN TUE
AS THE FORCING IS WEAKER...BUT THE CONDITIONAL THREAT OF
THUNDERSTORMS STILL EXISTS.

AN UPPER TROUGH AND ASSOCIATED SHORTWAVES WILL BRING PRECIP TO THE
AREA LATE THU EVENING INTO FRI NIGHT USING CONSENSUS TIMING (THE GFS
IS FASTER THAN THE ECMWF). COULD SEE THUNDER AS WELL.

A SFC HIGH DOMINATING NEXT WEEKEND WILL KEEP THE FORECAST DRY AND
COOLER AS 850MB TEMPS DROP TO AROUND 0C. TEMPS LOOK TO BE AS MUCH AS
10 DEGREES BELOW NORMAL OVER THE WEEKEND.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 111 AM EDT MON MAY 25 2015

SHOWERS WILL CONTINUE TO LIFT N ACROSS UPPER MI OVERNIGHT...
BRINGING DETERIORATING CONDITIONS. EXPECT KIWD/KCMX/KSAW TO FALL
TO LIFR OVERNIGHT. LIFR CONDITIONS WILL THEN PERSIST INTO THIS
AFTN. SOME IMPROVEMENT COULD OCCUR MID TO LATE AFTN AT KIWD/KSAW AS
WINDS SHIFT TO THE WSW BEHIND FROPA. IMPROVEMENT IS MORE
LIKELY TO OCCUR AT KSAW AS WINDS WILL HAVE A DOWNSLOPE COMPONENT.
MAY SEE IMPROVEMENT TO VFR THERE IN THE EVENING...PERHAPS EARLIER.
MEANWHILE...MOIST EASTERLY UPSLOPE FLOW OFF OF LAKE SUPERIOR INTO
THE KEWEENAW PENINSULA MAY RESULT IN VIS DROPPING TO VLIFR AT KCMX
THIS MORNING...BUT THERE IS LOW CONFIDENCE IN SUCH A LOW VIS
WITH RAIN PREVAILING. BETTER POTENTIAL FOR VLIFR WILL BE LATE THIS
AFTN/EVENING AS PCPN DIMINISHES OR ENDS WITH WINDS SHIFTING TO AN
UPSLOPE WESTERLY DIRECTION.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 255 AM EDT MON MAY 25 2015

LIGHT WINDS INCREASE TODAY AS A LOW PRESSURE SYSTEM MOVES ACROSS
WESTERN LAKE SUPERIOR.  EAST WINDS MAY REACH 25 KTS...STRONGEST OVER
WESTERN LAKE SUPERIOR AND ALSO NORTHERN LAKE MICHIGAN AND THE BAY OF
GREEN BAY. LOW SLIDES OVERHEAD ON MONDAY NIGHT SO THE WINDS WILL
DIMINISH. WINDS THE REST OF THE FORECAST PERIOD ARE EXPECTED TO STAY
AT OR BELOW 20 KTS. FOG WILL LINGER THROUGH WEDNESDAY MORNING AND
MAY BE DENSE AT TIMES. ONCE IT IS EVIDENT HOW EXPANSIVE THE FOG
IS...A DENSE FOG ADVISORY MAY BE NEEDED.
&&

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

$$

SHORT TERM...07
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...07



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