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000
FXUS63 KDTX 061611
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1111 AM EST THU MAR 6 2014


.AVIATION...

//DISCUSSION...

A VERY DRY PROFILE ASSOCIATED WITH DEPARTING HIGH PRESSURE WILL
MAINTAIN CLEAR SKIES BELOW 10KFT THROUGH THE TAF PERIOD. THE ONSET
OF DAYTIME HEATING HAS ALLOWED FOR AN INCREASE IN EASTERLY WINDS
OCCASIONALLY GUSTING OVER 15 KTS BUT A SHALLOW MIXED LAYER AND WEAK
AMBIENT WIND FIELD SHOULD GENERALLY KEEP GUSTS TO A MINIMUM.

//DTW THRESHOLD THREATS...

* NONE.

&&

.PREV DISCUSSION...ISSUED 341 AM EST THU MAR 6 2014

SHORT TERM...TODAY AND TONIGHT

A 1040MB SURFACE HIGH NOW CENTERED OVER SRN QUEBEC WILL BUILD INTO
NEW ENGLAND TODAY...WHILE AN ELONGATED RIDGE EXTENDS BACK ACROSS
LOWER MI. THE VERY DRY AMBIENT AIRMASS ASSOCIATED WITH THIS LARGE
LOW LEVEL ANTICYCLONE WILL RESIDE OVER SE MI THROUGH THE DAY. THERE
HAS BEEN A CONSIDERABLE AMOUNT OF HIGH CLOUDS OVER THE FORECAST AREA
TONIGHT ASSOCIATED WITH THE LARGE SRN STREAM SYSTEM TRACKING ACROSS
THE GULF COAST. THESE HIGH CLOUDS WILL SLOWLY PUSH OFF TO THE EAST
THIS MORNING...ALLOWING AMPLE SUNSHINE THROUGH THE DAY. LOW LEVEL
E-SE FLOW ASSOCIATED WITH THE DEPARTING SFC HIGH WILL SUSTAIN
SHALLOW ARCTIC AIR OVER THE REGION...WHICH WILL SUPPRESS AFTERNOON
MIXING DEPTHS. FULL EARLY MARCH SUN DOES HOWEVER SUGGEST MIXING
DEPTHS MAY BE A LITTLE HIGHER THAN MODEL SOUNDINGS. THIS WARRANTS
LEANING ON THE HIGHER END OF GUIDANCE HIGH TEMPS /MID TO UPPER 20S/.

THE SFC HIGH WILL LOOSEN ITS GRIP ON SE MI TONIGHT...THUS OPENING
THE DOOR LOW LEVEL WARM AIR ADVECTION UNDER S-SW FLOW. WEAK ASCENT
ALONG THE 285-295K ISENTROPIC SURFACES WILL LIFT NORTHWARD ACROSS
THE AREA THIS EVENING. MODEL SOUNDINGS SUGGEST THE FORCING WILL NOT
BE STRONG ENOUGH TO GENERATE MUCH CLOUD COVER. SO THERE SHOULD BE AT
LEAST SOME PERIOD OF GOOD RADIATIONAL COOLING POTENTIAL THIS EVENING
/DROPPING TEMPS DOWN INTO THE TEENS/ BEFORE SOUTHERLY FLOW INCREASES
OVERNIGHT AND CAUSES TEMPS TO SLOWLY RISE TOWARD DAYBREAK FRI.

LONG TERM...

REMNANT SUBSIDENCE INVERSION CENTERED DOWN TO 2 KFT AGL WITH AN
ADDITIONAL ROUND OF ANTICYCLONIC VORTICITY ADVECTION 12-18Z WILL
ALLOW SURFACE RIDGING TO EXTEND BACK ACROSS THE CENTRAL GREAT LAKES.
STRONG CLOSED LOW SYSTEM LIFTING INTO THE CAROLINAS WILL OFFER
SYSTEM SCALE SUBSIDENCE ON THE PERIPHERY WHICH SHOULD PROVIDE AN
ADDITIONAL COMPONENT TO LOCK THE SURFACE RIDGE IN PLACE. WARM AIR
ADVECTION WILL CERTAINLY BE OCCURRING AT THE SURFACE AND IT WILL
NEED TO BE GIVEN SUCH EXTREMELY LOW MIXING HEIGHTS. NICE MARCH
INSOLATION WILL HELP ALTHOUGH ALBEDO REMAINS HIGH. STILL FEEL
TEMPERATURES MAKING A RUN AT 40 IS GOOD...MODEL SIGNAL IS THERE THAT
COOLER TEMPERATURES MAY ACTUALLY BE IN THE HIGHER SURFACE PRESSURE
AREAS EAST OF THE GLACIAL RIDGE.

ARRIVAL AND AMPLIFICATION OF THE NEXT ROSSBY WAVE COUPLET OVER NORTH
CENTRAL CANADA WILL SEND A COLD FRONTAL BOUNDARY TOWARDS LOWER
MICHIGAN FRIDAY NIGHT. CYCLONIC VORTICITY SIGNATURE SUGGESTS THE
BOUNDARY WILL NEED TO BE DIRECTLY OVER THE TOP BEFORE THERE ARE ANY
PRECIPITATION CHANCES. THIS ALSO AGREES WITH WHAT SHOULD BE AN
OVERABUNDANCE OF DRY AIR THAT WILL NEED TO BE OVERCOME. LOW CHANCE
POPS LOOK GOOD FOR FRIDAY NIGHT. MODEL SOLUTIONS ARE SHOWING SOME
RATHER GLARING DIFFERENCES WITH REGARDS TO PRECIPITATION
AXIS/POTENTIAL FOR THE DAYTIME SATURDAY. VERY EASY TO SEE WHY THIS
IS WITH THE MODEL SOLUTIONS PROGGING THAT A LARGER FEATURE UPPER
LEVEL JETLET WILL DEVELOP DIRECTLY OVERHEAD. SOUTHEASTERN MICHIGAN
SEEMS TO BE SITUATED IN AN AREA OF HIGH UNCERTAINTY CONCERNING THE
AGEOSTROPHIC CIRCULATION. ALL OF THE MODELS ARE SUPPORTING A DECENT
SHORTWAVE TROUGH TO SLIDE THROUGH DURING THE DAY. COMBINE THIS WITH
SOUTHEASTERN MICHIGAN RESIDING ON THE COLD AND FAVORABLE SIDE OF THE
FRONTAL BOUNDARY AND HIGH CHANCE POPS ARE WARRANTED. MILDER
TEMPERATURES AND LIGHT QPF PRECLUDES MUCH OF AN ACCUMULATION.

MARINE...

SOUTHEASTERLY RETURN FLOW AROUND DEPARTING HIGH PRESSURE WILL BUILD
IN TODAY. WINDS WILL THEN VEER TO SOUTHERLY DIRECTION ON FRIDAY
AHEAD OF A COLD FRONT. EVEN THEN...WINDS ARE ONLY EXPECTED TO BE IN
THE 10 TO 20 KNOT RANGE WITH THE RELATIVELY STABLE SOUTHERLY FLOW
KEEPING GUSTINESS TO A MINIMUM.

&&

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

&&

$$

AVIATION.....SC
SHORT TERM...SC
LONG TERM....CB
MARINE.......CB


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