Area Forecast Discussion
Issued by NWS Duluth, MN

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 KDLH 050917
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
417 AM CDT SAT SEP 5 2015

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 414 AM CDT SAT SEP 5 2015

WARM AND WET WEATHER FOR THE UNOFFICIAL END OF SUMMER ACROSS
NORTHERN MINNESOTA. EXPECTING MULTIPLE ROUNDS OF SHOWERS AND
THUNDERSTORMS ACROSS THE WEEKEND WITH ABOVE NORMAL TEMPERATURES AND
UNCOMFORTABLY HIGH DEW POINTS FOR EARLY SEPTEMBER. HEAVY RAIN
LEADING TO POSSIBLE FLOODING IS THE PRIMARY CONCERN...THOUGH A FEW
STRONG TO SEVERE THUNDERSTORMS PRODUCING GUSTY WINDS AND HAIL ARE
ALSO POSSIBLE.

TODAY...ISOLATED CONVECTION ACROSS NORTHEAST MINNESOTA WILL WANE AS
A MID-LEVEL RIDGE AXIS MOVES ACROSS THE REGION. THIS WILL ALLOW FOR
PARTIAL CLEARING LEADING TO SOME DIURNAL HEATING. DEW POINTS IN THE
LOW 70S ACROSS THE MAJORITY OF THE CWA...WITH THE EXCEPTION FOR
ALONG THE LAKE SUPERIOR SHORELINE...ESPECIALLY ALONG THE NORTH SHORE
AND INLAND TO THE MN ARROWHEAD WHERE DEW POINTS WILL BE LIMITED TO
THE 60S. TEMPERATURES IN THE LOW TO MID 80S...WARMEST SOUTH OF THE
TWIN PORTS ALONG THE INTERSTATE 35 CORRIDOR WHERE TEMPS CLIMB INTO
THE MID 80S. THIS WILL LEAD TO THE HEAT INDEX REACHING THE MID TO
UPPER 90S ACROSS PINE AND BURNETT COUNTIES. WINDS OUT OF THE SOUTH
COULD BECOME GUSTY THIS AFTERNOON DEPENDING ON CLOUD COVER...FROM
BRAINERD TO MOOSE LAKE AND POINTS SOUTH WINDS COULD GUST UP TO
AROUND 20 MPH.

TONIGHT...SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS THE AREA WITH
MULTIPLE ROUNDS OF STORMS LIKELY ACROSS NORTH CENTRAL TO NORTHEAST
MINNESOTA. THESE STORMS WILL PRODUCE HEAVY RAIN...AND GIVEN LAST
NIGHTS RAINFALL AND THE EXPECTED ATMOSPHERIC CONDITIONS FLOODING IS
POSSIBLE. PWAT VALUES APPROACHING 2.0 INCHES IS ABNORMALLY HIGH FOR
EARLY SEPTEMBER AND WITH STORM MOTIONS OF 15-20KTS IN THE EVENING
THERE IS POTENTIAL FOR FLASH FLOODING. CURRENT 3-HR FLASH FLOOD
GUIDANCE FROM THE NORTH CENTRAL RIVER FORECAST CENTER IS RELATIVELY
HIGH AT 2-3.5 INCHES...BUT COULD SEE LOCALIZED AMOUNTS THIS HIGH.

MODELS ARE HAVING A TOUGH TIME WITH PLACEMENT OF THE BEST PRECIP DUE
TO UNCERTAINTIES ABOUT THE MID-LEVEL SHORTWAVE TROUGH THAT WILL RACE
ACROSS THE CENTRAL/NORTHERN PLAINS TODAY. HOPEFULLY 12Z SUITE OF
GUIDANCE HAS A BETTER HANDLE ON THIS...BUT FOR NOW IT SEEMS ANYWHERE
ACROSS NORTH CENTRAL TO NORTHEAST MINNESOTA HAS THE POTENTIAL FOR
HEAVY RAINFALL. WHILE THE BEST FORCING WILL BE ASSOCIATED WITH THE
MAIN UPPER LOW DEEPENING IN SOUTHERN CANADA...THE IMPULSE HEADED OUR
WAY WILL NOT HAVE MUCH TROUBLE KICKING OFF PRECIP DUE TO A WEAK CAP
AND CONSIDERABLE CAPE THAT WILL HAVE DEVELOPED BY LATE
TOMORROW....OVER 2000 J/KG CAPE. WEAK WINDS THROUGH THE COLUMN WILL
LEAD TO JUST AROUND 20 KTS OF DEEP LAYER SHEAR.

OTHERWISE TONIGHT SHOWERS AND STORMS MAY MOVE INTO FAR NORTHWEST
WISCONSIN BUT NOT TOO FAR BEYOND THE MN/WI STATE LINE UNTIL LATE
TONIGHT. LOWS IN THE 60S.

SUNDAY...ANOTHER BREAK IN CONVECTION EARLY IN THE DAY THEN A CHANCE
FOR STORMS IN THE AFTERNOON...SOME OF WHICH COULD BE STRONG TO
SEVERE. THERE ARE SEVERAL FACTORS WORKING AGAINST THE CHANCE FOR
STORMS ON SUNDAY...INCLUDING AN AREA OF HIGH PRESSURE BUILDING
ACROSS THE CENTRAL/NORTHERN PLAINS LATE IN THE DAY...QUESTIONS ABOUT
JUST HOW STRONG THE NEXT MID-LEVEL SHORTWAVE WILL BE...AND BEST
WINDS ALOFT MAY NOT LINE UP WITH THE BEST INSTABILITY. THAT
SAID...SHOULD STORMS FIRE IN THE AFTERNOON THE DEEP LAYER SHEAR WILL
BE BETTER THAN SATURDAY WITH MORE LIKE 30-40KTS WITH 2500+ J/KG CAPE
FOR THUNDERSTORMS. AS LONG AS THE UPPER LEVEL FORCING IS IN PLACE
AND DIURNAL HEATING IS STRONG ENOUGH WE SHOULD SEE ISOLATED TO
SCATTERED STORMS IN THE AFTERNOON. WHILE PWATS REMAIN VERY
HIGH...THE BETTER SHEAR COULD RESULT IN A FEW STORMS PRODUCING GUSTY
WINDS AND LARGE HAIL AS WELL. HAIL POTENTIAL IS CHALLENGED BY SUCH A
WARM AIRMASS RESULTING IN A LARGER MELTING LAYER...BUT THIS
ENVIRONMENT WILL BE CAPABLE OF PARTAKING AT LEAST A FEW LOW-END
SEVERE STORMS. HIGHS IN THE LOW TO MID 80S AND DEW POINTS IN THE LOW
70S. STRONGER WINDS OUT OF THE SOUTH-SOUTHWEST WILL LIKELY BE TOO
POWERFUL FOR A LAKE BREEZE RESULTING IN WARM AIR REACHING THE
SHORELINE. WINDS GUSTING UP TO AROUND 25 MPH WITH A FEW PEAK GUSTS
TO 30 MPH POSSIBLE.

SAT/SUN TOTAL RAINFALL...AROUND AN INCH IN NORTHWEST WISCONSIN TO
ONE TO TWO INCHES IN NORTHEAST MINNESOTA. LOCALLY HIGHER AMOUNTS
MOST LIKELY FROM LEECH LAKE TO THE IRON RANGE AND THE
INTERNATIONAL BORDER.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 414 AM CDT SAT SEP 5 2015

A COLD FRONT IS EXPECTED TO BE CONTINUING TO MOVE THROUGH THE
NORTHLAND...FROM WEST TO EAST...SUNDAY EVENING INTO EARLY MONDAY.
THERE COULD BE STRONG TO SEVERE STORMS DURING THE EVENING. THE
SREF/GFS ARE INDICATING UP TO 2500 J/KG OF MOST UNSTABLE CAPE AND UP
TO AROUND 30 KNOTS OF DEEP LAYER WIND SHEAR. THE BETTER SHEAR WILL
BE TRAILING BEHIND THE FRONT...SO STORMS NEAR THE COLD FRONT MIGHT
BE ABLE TO TAP INTO ENOUGH SHEAR TO BECOME WELL ORGANIZED.
PRECIPITABLE WATER VALUES WILL BE QUITE HIGH...BETWEEN 1.75 AND 2
INCHES...SO EFFICIENT RAINFALL PROCESSES COULD RESULT IN HEAVY
RAINS.

COOLER WEATHER WILL SETTLE INTO THE NORTHLAND EARLY NEXT WEEK. HIGH
TEMPERATURES ON MONDAY WILL BE IN THE MIDDLE TO UPPER 70S...BUT ONLY
THE MIDDLE 60S TO LOW 70S BY WEDNESDAY. HIGH PRESSURE WILL PROVIDE
DRY AND SUNNY WEATHER FOR MONDAY. TUESDAY MIGHT ALSO BE DRY...BUT
THE GEM IS INDICATING AN UPPER LEVEL LOW AND ITS TROUGH AXIS WILL
SWING THROUGH THE CANADIAN BORDER AND MN/WI REGION TUESDAY AFTERNOON
AND NIGHT. THIS MIGHT RESULT IN SOME RAIN SHOWERS ACROSS THE
NORTHLAND.

THE GFS AND ECMWF ARE INDICATING A SHORTWAVE TROUGH AND A FRONTAL
BOUNDARY MIGHT MOVE THROUGH THE REGION WEDNESDAY AFTERNOON AND
NIGHT...PROVIDING ANOTHER OPPORTUNITY FOR SHOWERS.

EVEN COOLER WEATHER WILL LIKELY MOVE INTO THE REGION LATE THIS WEEK
IN THE WAKE OF THE FRONTAL BOUNDARY. HIGHS MIGHT ONLY BE IN THE
LOWER 60S FOR THURSDAY THROUGH SATURDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 108 AM CDT SAT SEP 5 2015

A SHORTWAVE WILL MOVE NORTHEASTWARDS INTO WESTERN ONTARIO BY 12Z.
THIS IS BRINGING SHOWERS AND THUNDERSTORMS TO KHIB AND KINL.
SINCE KDLH IS ON FAR SOUTHERN PERIPHERY OF SHOWER ACTIVITY PER
RADAR TRENDS...KEPT IN AS VCSH. AS THE NIGHT PROGRESSES FOG WILL
BE OF CONCERN. LATEST GFS AND NAM MOS GUIDANCE HINT AT FOG
FORMATION AT ALL TERMINALS. MOST CONFIDENT AT KINL DUE TO SHOWER
ACTIVITY...SO BROUGHT DOWN TO MVFR VISBY. LESS CERTAIN AT OTHER
SITES...AS SOME HAVE RECEIVED NO PRECIP THIS EVENING...AND WINDS
MAY STAY HIGH ENOUGH TO PREVENT FORMATION. SO BROUGHT VISBY UP TO
IFR AND LEFT IN AS A TEMPO.

BEHIND THE SHORTWAVE...RIDGING WILL PROVIDE A LULL IN
PRECIPITATION UNTIL SATURDAY AFTERNOON. THIS WILL RESULT IN VFR
CONDITIONS RETURNING AFTER ANY FOG DISSIPATES. ANOTHER SHORTWAVE
WILL MOVE IN FROM THE EASTERN DAKOTAS BRINGING MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS TO THE AREA SATURDAY AFTERNOON/EVENING.
DUE TO THE LOW LEVEL JET BROUGHT IN A MENTION OF LLWS TO ALL
TERMINALS LATE IN THE FORECAST.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  79  65  82  60 /  40  70  60  50
INL  80  64  81  54 /  60  80  60  40
BRD  85  68  84  57 /  40  70  50  30
HYR  85  71  84  60 /  30  40  70  70
ASX  88  68  86  62 /  20  40  60  80

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&

$$

SHORT TERM...JJM
LONG TERM...GROCHOCINSKI
AVIATION...WL


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