Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI

Home | Current Version | Previous Version | Graphics & Text | 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
000
FXUS63 KDTX 241358
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
958 AM EDT SUN APR 24 2016

.UPDATE...

THE LIGHT SHOWERS ACROSS WEST CENTRAL LOWER MI HAVE BEEN
DISSIPATING AS THEY WORK EAST WHERE THE AIRMASS IS MUCH DRIER /PER
12Z DTX SOUNDING/. THERE ARE ADDITIONAL LIGHT SHOWERS MOVING
ACROSS CENTRAL LAKE MI ATTM. THESE ARE LOCATED WITHIN A RIBBON OF
STRONGER FRONTAL FORCING NEAR 850MB. MUCH OF THIS FORCING WILL
REMAIN WEST OF THE FORECAST AREA THIS AFTERNOON...WHERE BETTER LOW
LEVEL INFLOW REMAINS FOCUSED. SO MUCH OF THESE SHOWERS ARE
EXPECTED TO DIMINISH AS THEY HEAD TOWARD THE SAGINAW VALLEY THIS
AFTERNOON. BETTER CHANCES FOR RAIN LOOK TO OCCUR LATER IN THE
AFTERNOON/EVENING AS MID LEVEL FGEN EXPANDS FROM NORTHERN
WISCONSIN INTO NORTHERN LOWER MI. THIS FORCING WILL BRUSH THE
NORTHERN SAGINAW VALLEY AND THUMB LATE TODAY AND WILL CONTINUE TO
WARRANT A CHANCE OF LIGHT RAIN IN THESE LOCALS. AN UPDATE WILL BE
ISSUED MAINLY TO PUSH BACK THE TIMING OF THE RAIN SHOWERS ACROSS
THE NORTH AND REDUCE POPS SOUTH OF SAGINAW THIS AFTERNOON/EVENING.

&&

.AVIATION...ISSUED 652 AM EDT SUN APR 24 2016

HIGH PRESSURE WILL CONTINUE TO HOLD THROUGH THE DAY WHILE AT THE
SAME TIME THE NEXT LOW PRESSURE SYSTEM WILL BE MOVING EAST TOWARDS
THE REGION.  HIGHER CLOUDS WILL SLOWLY INCREASE THROUGH THE DAY AS
SOUTHEASTERLY FLOW CONTINUES.  SLIGHT CHANCE FOR RAIN SHOWERS WILL
BE POSSIBLE ACROSS THE NORTHERN CWA TODAY ESPECIALLY AT MBS.
CONFIDENCE IS TOO LOW AT THE MOMENT TO INCLUDE RAIN SHOWER MENTION
IN THE TAF.

//DTW THRESHOLD PROBABILITIES...

* HIGH IN CEILING ABOVE 5KFT THROUGH SUNDAY EVENING

&&

.PREV DISCUSSION...ISSUED 308 AM EDT SUN APR 24 2016

DISCUSSION...

A MILDER DAY IS STILL ANTICIPATED TODAY AS SOUTHERLY FLOW GRADUALLY
INCREASES IN RESPONSE TO STRENGTHEN WEST TO EAST FRONTAL BOUNDARY
POSITIONED TO THE NORTH OF THE REGION. THE FRONTOGENESIS WILL OCCUR
AS LOW PRESSURE TRACKS INTO THE GREAT LAKES FROM THE PLAINS/UPPER
MIDWEST AND PULLS MILDER AIR NORTH INTO THE GREAT LAKES WHILE LARGE
UPPER LOW REMAINS ANCHORED OVER EASTERN CANADA AND HOLD THE EXISTING
WEAKER FRONT IN PLACE DESPITE THIS PUSH OF MILDER AIR IN THE AREA.

SHOWER CHANCES WILL INCREASE TODAY INTO TONIGHT...BUT REMAIN NORTH
OF I-69 FOR THE MOST PART...WITH THE MOST PERSISTENT AREA OF RAIN
FOCUSED WELL NORTH OVER NORTHERN LOWER MICHIGAN ALONG AFOREMENTIONED
FRONTAL BOUNDARY AND FGEN FORCING STEADILY INCREASES WITH THE
APPROACH OF THE LOW PRESSURE SYSTEM FROM THE WEST. THE UPPER
LEVEL SHORTWAVE RESPONSIBLE FOR THIS LOW WILL WEAKEN CONSIDERABLE
LATE TODAY INTO MONDAY/MONDAY NIGHT AS IT TRACKS INTO STRONG
CONFLUENCE UPPER FLOW ON SOUTHERN EDGE OF LARGE UPPER LEVEL LOW
OVER EASTERN CANADA.

STILL...AS THE REMAINS OF THIS SYSTEM RIPPLE THROUGH THE CENTRAL
GREAT LAKES...SHOWER CHANCES WILL INCREASE AS STATIONARY WEST TO
EAST BOUNDARY SINKS SOUTH THROUGH LOWER MICHIGAN DURING THE MONDAY
AFTERNOON TO MONDAY NIGHT TIME FRAME. WITH WEAK TO MODEST LOW LEVEL
INSTABILITY IN PLACE SOUTH OF THE FRONT BY THAT TIME AS TEMPERATURES
CLIMB INTO THE LOWER 70S...THUNDERSTORMS REMAIN A DECENT POSSIBILITY
WITH A FEW STRONGER STORMS NOT OUT OF THE QUESTION. AT THE VERY
LEAST...EXPECT LOCALLY HEAVY RAINFALL WITH SOME OF THIS ACTIVITY
LATE MONDAY INTO MONDAY NIGHT AS LOW LEVEL CONVERGENCE ALONG THE
FRONT INCREASE AS THE LOW PROGRESS THROUGH LOWER MI.

WHILE LINGERING SHOWERS WILL BE POSSIBLE INTO EARLY TUESDAY...DRY
WEATHER CAN GENERALLY BE EXPECTED MUCH OF TUESDAY ON THROUGH MUCH IF
NOT ALL OF WEDNESDAY AS HIGH PRESSURE SETTLES SOUTHEAST INTO THE
AREA AS THE LOW PRESSURE PASSES TO THE EAST AND FRONTAL BOUNDARY IN
QUESTION SINKS SOUTH INTO THE OHIO VALLEY. THIS WILL ALSO BRING
COOLER WEATHER WITH HIGH TEMPERATURES AVERAGING IN THE MID 50S ON
TUESDAY AND WEDNESDAY...BUT MUCH COOLER ALONG LAKE HURON WITH STEADY
NORTHEAST FLOW OFF OF COOL WATERS.

ANOTHER UPPER LEVEL SHORTWAVE FROM THE PACIFIC REGION WILL UNDERGO A
SIMILAR FATE LATE WEDNESDAY INTO THURSDAY AS IT SHEARED EAST ALONG
THE SOUTHERN EDGE OF THE LARGE EASTERN CANADIAN UPPER LOW. BY THIS
TIME...THE UPPER PATTERN IN GENERAL IS BEGINNING TO TAKE ON A MORE
BLOCKY PATTERN...SO THE AFFECTS OF THIS SECOND SYSTEM MAKE BE A BIT
LESS THAN AS ITS PREDECESSOR AS IT RUNS INTO A STRONG RIDGE
POSITIONED OVER THE AREA ALONG SOUTHWESTERN EDGE OF CANADIAN UPPER
LOW. THAT SAID...SHOWER CHANCES WILL ONCE AGAIN INCREASE LATE
WEDNESDAY INTO THURSDAY AS MOISTURE IS PULLED NORTHEAST INTO THE
AREA AND OVERRUNS COOL/DRY AIRMASS ALONG SOUTHERN EDGE OF SPRAWLING
HIGH PRESSURE OVER/NORTH OF THE GREAT LAKES.

YET ANOTHER UPPER LOW PRESSURE/SHORTWAVE DIGS INTO THE WESTERN AND
CENTRAL CONUS FROM THE PACIFIC LATE IN THE FORECAST AND EJECTS EAST
INTO THE UPPER MIDWEST AND GREAT LAKES BY THE MIDDLE OF NEXT
WEEKEND. WITH THE EASTERN CANADA LOW PRESSURE FORECAST TO SHIFT EVER
SO SLIGHTLY TO THE EAST AND NORTHEAST...THIS SYSTEM MAY HAVE A
BETTER CHANCE OF PRODUCING WIDESPREAD RAIN. CONFIDENCE THIS FAR OUT
IS VERY LOW...HOWEVER...ESPECIALLY GIVEN THE BLOCKY/SPLIT FLOW
UPPER PATTERN OF SPRING IN PLACE.

MARINE...

HIGH PRESSURE WILL BE IN THE PROCESS OF MOVING OFF TO THE EAST TODAY
AS THE NEXT LOW PRESSURE SYSTEM APPROACHES THE GREAT LAKES REGION
FROM THE WEST.  LIGHT SOUTHEASTERLY FLOW WILL CONTINUE ACROSS THE
AREA TODAY AHEAD OF THE FRONTAL BOUNDARY. THIS BOUNDARY WILL AFFECT
THE REGION LATER TODAY INTO MONDAY BRINGING AN INCREASE IN THE WINDS
ON MONDAY WITH POTENTIAL FOR GUSTS IN THE 25 TO 30 KNOT RANGE. THIS
MAY LEAD TO THE POTENTIAL FOR SMALL CRAFT CONDITIONS ALONG THE LAKE
HURON SHORELINE DURING THIS TIME. HIGH PRESSURE THEN BUILDS BACK IN
LATER TUESDAY INTO WEDNESDAY.

HYDROLOGY...

A LOW PRESSURE SYSTEM WILL PUSH EAST TOWARDS THE GREAT LAKES TODAY
PULLING A FRONTAL BOUNDARY ACROSS THE AREA ON MONDAY.  THIS WILL
BRING AN INCREASE IN RAIN CHANCES LATER TODAY ACROSS THE NORTH WITH
INCREASING CHANCES MONDAY INTO MONDAY NIGHT.  EXPECTED RAINFALL
TOTALS AT THIS TIME RANGE BETWEEN HALF AN INCH TO AN INCH. A FEW
THUNDERSTORMS WILL ALSO BE POSSIBLE ON MONDAY WHICH MAY LEAD TO
LOCALLY HIGHER RAINFALL AMOUNTS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

UPDATE.......SC
AVIATION.....SS
DISCUSSION...DG
MARINE.......SS
HYDROLOGY....SS


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).



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