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Area forecast discussion 
National Weather Service Gaylord Michigan
747 PM EDT Wednesday Apr 23 2014

issued at 403 PM EDT Wednesday Apr 23 2014

A storm system organizing east of The Rockies...will move into the
southern Great Lakes Thursday before exiting northeast into Quebec
Friday. This pattern will generate a round of rain and nearly
seasonal temperatures across northern Michigan Thursday night and

Some sun and slightly below normal temperatures will return to
northern Michigan this a large area of Canadian high
pressure drops into the upper Midwest and Great Lakes.

Another round of rain and continued cool temperatures in the 40s...
are expected to to begin the upcoming work a plains system
lifts into the Ohio Valley.


issued at 746 PM EDT Wednesday Apr 23 2014

No big changes this hour. Thicker high clouds continue to stream
northwest-southeast into northern Michigan...thickest across the SW counties. Biggest
forecast problem tonight will be temperatures. Very low surface dewpoints and
winds going calm certainly suggest temperatures May Tank quickly this
evening but thickening/lowering high-middle clouds will likely have
some impact on the temperature fall...especially later on. Given current
surface dewpoints...lows dipping into the teens for some spots
certainly within the envelope of possibilities. Possibly over the
east/NE parts of the County Warning Area where cloud cover will be thinner. But right
now believe that most areas will end up in the 20s per going
forecast. Will see how it GOES.


Short term...(this evening through tonight)
issued at 403 PM EDT Wednesday Apr 23 2014

..a touch chilly tonight...

High impact weather potential: none.

Larger scale overview: classic set-up for the sun-filled weather we
are experiencing...with elongated surface high stretched north/south
across the western lakes just downstream of sharp middle level ridging
over the upper Mississippi Valley. Deep layer dry wedge
overhead...evident by 0.14 precipitable water values on local 12z sounding and
current surface dewpoint depression of 40 degrees or more (plenty of
single digit dewpoints). Initial stages of top-down saturation well
ahead of intermountain west troughing helping drive some thin cirrus
back across the western lakes into parts of northern lower Michigan. least for the time being...remains progressive...
suggesting our bout of dry weather will soon be a thing of the past
(see long term section below for all those good details).

Primary forecast concerns/challenges: minimal. Cloud and temperature
trends about the only challenges tonight.

Details: high clouds will slowly be on the increase...with deep dry
layer through the middle and lower level of the airmass preventing any
shower activity until Thursday. Current very dry airmass and
expected quick decoupling should lead to an excellent nocturnal
temperature response. Overnight cirrus might temper this some...but
given current dewpoints...favor the colder end of the guidance
spectrum...which features lows in the lower and middle 20s across
interior regions...just a few degrees "warmer" near the big waters.

Long term...(thursday through wednesday)
issued at 403 PM EDT Wednesday Apr 23 2014

... Headed for northern Michigan late Thursday and

High impact weather potential: high confidence in precipitation
event late Thursday through late Friday. Low confidence in next
weeks weather.

Pattern synopsis/forecast: upper low located over British Columbia Canada with
trough across The Rockies will move across the Great Lakes Saturday
and into the northeast US Sunday. As energy drops over The Rockies
expect surface low to develop over the central/Southern Plains and
track northeast towards Michigan. Upper low and strong Pacific jet
energy currently west of Alaska is expected to drop into California
Saturday and close off somewhere across the central US
Sunday...meandering slowly east early next week. Pattern should slow
next week as system tries moving northeast in North Atlantic block.

Primary forecast concerns (near term): precipitation chances for
Thursday and precipitation type for Friday night.

Near term (thursday through saturday): increasing return flow ahead of
approaching surface low will pull Gulf moisture into the region and
precipitation chances until low moves through early Saturday. Warm
front associated with the low lifts NE through the region Thursday
but may be hard to get precipitation with very dry air currently
over the region. Dewpoints currently running in the single digits.
Precipitation chances increase toward evening and overnight surface low passes
through Michigan with strong vorticity advection aloft as shown on
pv15 surfaces. Convection forming over MO/Tennessee could hinder northward
transport of moisture but should be enough lift and moisture to get
some rain. Thermal profiles show late night precipitation could mix
with snow over eastern upper and maybe higher elevations of northern
lower. Moisture is quickly pulled east early Friday with the surface low
but upper low crosses northern Michigan and could be some
showers...especially late Friday across eastern upper. Thermal
profiles show late Friday precipitation as some snow or a mix.

Medium range (saturday and sunday): we should be able to get some
nice weather in between the two storm systems this weekend as high
pressure moves quickly across the Great Lakes.

Outlook (tuesday and wednesday): confidence low on this part
of the forecast with next surface low moving from central US into
Michigan/Ohio Valley. Track uncertain at this time but cold air in
place north of the low could set up messy weather again early to middle
next week.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 746 PM EDT Wednesday Apr 23 2014

Straight VFR flight conditions anticipated through the day
Thursday. Middle and high clouds will thicken and lower later tonight
through the day on Thursday as upstream system in the plains today
slowly works it/S way into the region. But ceilings will remain VFR at
least through early Thursday evening with any precipitation holding off
until after 00z.

Winds go calm tonight but pick back up Thursday morning from the
southeast. Some gustiness will develop Thursday afternoon especially at
tvc/mbl as the aforementioned system gets closer...with some gusts
into the 20-25 knot range possible.


issued at 335 am EDT Wednesday Apr 23 2014

Winds expected to go light overnight...backing more easterly
while doing so. East to southeast winds tomorrow ahead of
approaching low pressure. Winds will increase in speed...although
both speed and wave action should remain below Small Craft Advisory criteria.


Apx watches/warnings/advisories...



short term...msb
long term...kf