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Area forecast discussion 
National Weather Service Gaylord Michigan
310 PM EDT Sat Jul 4 2015

Near term...(this evening through tonight)
issued at 303 PM EDT Sat Jul 4 2015

Pattern synopsis/forecast: low amplitude ridging moving into the
Great Lakes tonight as weak high pressure slowly pushes east toward
the Atlantic coast.

Primary forecast concerns: a few showers/thunderstorms over southeast parts
of the area early in the evening. Potential fog development late.

Tonight...widely scattered shower/thunderstorm chances will linger into early
evening over the far southeast /Gladwin-Iosco-Arenac counties/ in
proximity to a weak h9-800 mb Theta-E gradient laying across the
central parts of Michigan. Once this activity diminishes...little
in the way of cloud cover expected across northern Michigan
overnight outside of some scattered middle/high clouds potentially
sliding into the area later from convection over Wisconsin. We may
see patchy fog develop after midnight as the boundary layer cools
and surface dewpoints gradually creep up through the 50s. Min temperatures fairly
normal for early July...generally in the 50s.

&&

Short term...(sunday through tuesday)
issued at 303 PM EDT Sat Jul 4 2015

High impact weather potential: thunderstorms Monday night may
produce gusty winds and locally heavy downpours.

Pattern synopsis/anticipated evolution: high pressure over the eastern
Great Lakes will drift further east Sunday/Monday. This will allow
southerly winds to strengthen...and an increasingly warm/moist
airmass will overspread the region. A middle level impulse will move
into the western Great Lakes late Monday...and an associated cold front
will bring showers/storms to the region beginning Monday night.

Sunday and Sunday night...increasing Summer warmth expected. Winds
across the area will become southerly as decent warm air advection commences on
back side of aforementioned high pressure over the eastern Great Lakes.
800 mb temperatures moderating to near +17c and sunshine/mixing will
allow high temperatures to reach the upper 70s eastern upper and the low-
middle 80s across much of northern lower. Model soundings and expected low
level moisture will support diurnal cumulus. In fact...both NAM/GFS
suggest a small risk for pop up late day showers/storms over
interior northern lower...with ~1300 j/kg MLCAPE (!?). However...given
respectable cap just above 700 mb...dry going forecast...and limited
conditional coverage...will tentatively keep the Sunday afternoon
forecast dry at this time - but can/T strictly rule out a shower or
two. With steady southerly breezes Sunday night...it/ll remain warm.
Under clear to partly cloudy skies...lows will dip only into the
upper 50s to middle 60s.

Monday...the warming continues. Tightening pressure gradient ahead
of approaching cold front will result in breezy and warm
conditions...as highs reach well into the 80s most areas. Expect
some cumulus to form...along with increasing higher clouds late ahead of
said cold front. Expect associated showers/storms to mainly hold off
until Monday night.

Monday night and Tuesday...conditions appear ripe for a decent shot
at precipitation Monday night. In addition to cold front that will
traverse northern Michigan...pwat/S around 2.0 inches...freezing levels
around 14kft...and wind fields associated with 40-50 knots 800 mb low level jet
suggest rainfall rates may locally/briefly be impressive. And to a
lesser extent...500 mb winds approaching 35 kts together with modest
instability may also support gusty winds within some of the stronger
storms /see Storm Prediction Center day 3 marginal risk/. All said...a period of showers
and thunderstorms is a good bet across most of the area. Models
differ on how quickly front /and therefore precipitation/ will push east of
the area. At this time...will taper precipitation off /coverage and timing/
across forecast area from southeast to northwest. Clouds and lingering precipitation in
Post-frontal regime will support much cooler temperatures...with
highs on Tuesday only in the middle 60s to Lower-Middle 70s anticipated.

&&

Long term...(tuesday night through saturday)
issued at 303 PM EDT Sat Jul 4 2015

High pressure will continue to build into the region behind the
frontal passage earlier in the week. After a cool day
Tuesday...temperatures will slowly work back to normal by Saturday...with
most of the week ranging through the 70s. A late week system passing
to our south is resulting in slight chance probability of precipitation for Thursday. There
is a bit of uncertainty in how far north the deformation axis will
be...leading to the slight chances for our area...but given recent
trends for systems to drift or remain south as the days grow closer
I expect these chances will decrease. The next good chance for rain
could be over the weekend as another low moves into the region from
the plains. A main driver of this is going to be shortwave energy
ejecting from an 500 mb low off the California coast...and as expected there is
a good deal of divergence in how models are handling this. Pop
chances are only slight for now...as plausible solutions range from
dry to chances for some thunderstorms. General thoughts at this time
are a southward adjustment of solutions more favorable for
thunderstorms here...placing better instabilities and thunderstorm
chances to our south along the warm front but still giving US some
rain.

&&

Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 119 PM EDT Sat Jul 4 2015

A few rain showers/thunderstorms and rain possible this afternoon over NE lower Michigan...south
of apn. So no trouble anticipated at taf sites. Hazy conditions
/mainly due to smoke from Canadian fires/...with diurnal cumulus
developing over inland areas. Areas of fog after midnight
tonight...with IFR visibilities possible at pln/mbl. After early morning
fog dissipates...VFR conditions expected on Sunday with light
winds.

&&

Marine...
issued at 303 PM EDT Sat Jul 4 2015

High pressure centered over Southern Lower Michigan will maintain weak
winds and waves through Sunday. Small craft advisories are not
anticipated. Scattered PM T-storms are expected into early this evening
in NE lower Michigan...south of Alpena. Some of these could bring brief
gusty winds to the nearshore waters. The gradient will tighten on
Monday in advance of a strong cold front that will move through
the area Monday night. This could result in small craft headlines
for parts of the area. Cooler air and a lighter wind regime
anticipated for midweek.

&&

Apx watches/warnings/advisories...
Michigan...none.
LH...none.
Lm...none.
Ls...none.
&&

$$

Near term...keysor
short term...Smith
long term...alm
aviation...keysor
marine...keysor

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