Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Detroit/Pontiac Michigan
310 am EDT Friday Mar 14 2014
Short term...today and tonight
Brisk southwest winds will allow temperatures to rise solidly into
the 40s...with the potential of 50 degrees...as witnessed at
Minneapolis Minnesota yesterday evening ahead of the the cold front.
Msp also had a snow depth of 10 inches to start the day. Our issue
looks to be more with clouds. Early morning stratus has pushed north
per 11u-3.9u satellite imagery. Although the low level inversion
will continue to strengthen...the 925-850 mb levels will continue to
dry...and do think we will see sufficient mixing to maintain clear
skies and allow for morning sunshine across Southeast Michigan. The
afternoon hours are expected to feature an increase in high
clouds...then down low as the surface frontal convergence/Theta-E
ridge axis arrives late in the day. Moisture is overall lean...but
upper level trough/energy over the Dakotas is substantial and worthy
of carrying slight chance probability of precipitation late today/this evening...especially
if one sides with the GFS. The boundary layer should be initially
too warm to support snow (if precipitation even materializes)...but
as the night wears on and low level cold advection kicks in...a
slight chance of light snow showers toward sunrise seems in order as
secondary cold front descends south through the central Great Lakes
underneath the northwest flow.
Quiet pattern setting up over the weekend into early next week as
high pressure settles eastward through the region. This high will
bring another period of rather chilly conditions...especially during
the Sunday/Monday time frame as highs return to the 20s with lows in
the single digits to around 10.
A rather vigorous storm system will evolve from the southwest Continental U.S.
Into the Tennessee/southern Ohio Valley...but current model runs
continue to show the aforementioned cold airmass spreading into the
area limiting any northward push of this system into lower Michigan.
The next significant Pacific shortwave to the mean upper trough over
the eastern 2/3 of the Continental U.S. Will be entering the Pacific northwest
late this weekend just as the first system bypasses the area to the
south. This system develops to our west and takes a track over or
just west of the area as mean upper trough axis becomes established
over the upper Midwest.
This will bring moderating temperatures into the end of this
forecast period as highs climb back 40 or better by Wednesday and
Thursday. Depending on the exact track of this system...a mix or
rain or snow can be expect in the time frame as well as the high
pressure that keeps much of the period quiet becomes re-positioned
over Quebec/New England.
Gusty winds will persist over Lake Huron as low pressure crosses to
the north of the area today. Southwest flow will increase with the
passage of a warm front this morning...and then veer to northwest
tonight as a trailing cold front pushes into the central Great
Lakes. Additional cold air will spill into the area over the weekend
as a large area of high pressure begins to build into the region.
All in all...while conditions will not be ideal...expect wind gusts
to remain below gales...even as the deeper cold air surges into the
region on northerly winds this weekend.
Aviation...issued 1156 PM EDT Thursday Mar 13 2014
Steady warm air advection prompting some increase in MVFR stratus
across central lower Michigan. This moisture will shift through the
northern terminals during the early morning hours. Otherwise
conditions will will remain in VFR through Friday. A 10 knot
southwest gradient will hold firm tonight with some strengthening of
the flow commencing in advance of a cold front on Friday. The
strengthening wind field in steady warm air advection may yield some
gusts by afternoon /20-25 knots/ despite the limited mixing
potential. Middle cloud thickens again as the cold front shifts
through late in the day. Some increase in low level moisture as
colder air returns will promote some lower stratus development and
may provide a low chance for light precipitation by Friday
//Dtw threshold threats...
* medium confidence in ceiling below 5000 feet Friday night.
Lake St Clair...none.
Michigan waters of Lake Erie...none.
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at www.Weather.Gov/Detroit (all lower case).