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Area forecast discussion 
National Weather Service Gaylord Michigan
354 PM EDT Friday Aug 1 2014

issued at 352 PM EDT Friday Aug 1 2014

Very pleasant weather with seasonable temperatures will be the rule
for the next several days. Only small areas of northern Michigan
will see the possibility of an isolated light rain shower...mainly
during the afternoon hours.


Short term...(this evening through tonight)
issued at 352 PM EDT Friday Aug 1 2014

... Mild night...

High impact weather potential: none.

Pattern synopsis/anticipated evolution: overhead troughing
remains...although per water vapor imagery...some relaxation has
begun with noted height rises beginning to push into the far western
lakes. Embedded low amplify waves continue to drop through this trough pinwheeling through southeast Wisconsin...with another
dropping across Western Lake Superior. Former is helping drum up
some scattered showers and storms in Wisconsin...with the backside
of the latter kicking off isolated activity into Minnesota. Closer
to home...dewpoints have done their aggressive mixing out as
advertised...with current reading in the 40s and 50s. More moist
conditions just off to our south...just enough so to help ignite a
few showers and storms over central and Southern Lower Michigan. So
far just too dry across northern lower...although will continue to
monitor northeast lower/eastern Upper Lake breeze convergence axes
for some isolated activity (some agitated cumulus fields per local visible
satellite imagery).

Primary forecast concerns/challenges: nothing high impact.
Temperature/cloud trends and possible evening shower activity.

Details: simple persistence is key...and lessons Learned yesterday
apply today. Mixing out of low level moisture really doing the
number on preventing shower activity...and see little reason that
will change into early this evening. Still think a shower or two may
fire where moisture convergence is maximized along lake breeze
axes...namely northeast lower and eastern Upper Michigan. Isolated
wording will do for now in these areas through early this evening.
Otherwise...a quiet night is expected...with light/calm winds and a
cooling boundary layer promoting some patchy fog development.
Temperatures tonight will range from the upper 40s to middle 50s.


Long term...(saturday through friday)
issued at 352 PM EDT Friday Aug 1 2014

..pretty good weekend ahead/rain threat increases later Sunday and

High impact weather potential: minimal.

Pattern synopsis/forecast: persistent upper troughing remains from
James Bay southward through the Great Lakes/Ohio Valley and down to
the central Gulf Coast. Another upper low was over the northeast
Pacific...making up the eastern portion of a developing -wpo/Omega
block. Ridging in between these features over western North America
is getting flattened by high latitude upper low over the northwest
territories. Water vapor imagery reveals several smaller scale
features wrapping around the James Bay low (two of which are
spinning through the Minnesota arrowhead). Surface pressure pattern
is Pretty Flat with a remnant surface low east of James Bay
reflecting its parent circulation aloft...with minimal pressure
gradient across the upper Great Lakes/Midwest and northern/Central
Plains. Height falls associated with northwest territories short
wave trough is pushing a cold front across northwest
Manitoba/central Saskatchewan.

Trough magnitude will weaken during the weekend but the trough axis
will remain in place...with new short wave energy dropping across
the upper lakes early next week to help maintain the trough
position. Short wave energy over northeast Minnesota will swing
through Michigan overnight/Saturday morning...with central Canada
cold front the next feature of interest as it drops in from the
northwest and moves into Michigan Sunday night/Monday.

Primary forecast concerns (near term): precipitation chances mainly
Sunday though will probably still have to take a look at potential
diurnally driven convection given recent trends.

Near term (saturday/sunday): Saturday continues the theme of recent
days...with still somewhat cool low/middle level temperatures and
marginal boundary layer moisture along with weak forcing...and
whether this combination rises up to being worthy of a chance of
precipitation. Minnesota short wave trough will swing through
northern Michigan Saturday morning though it appears with little
fanfare...and boundary layer moisture may be even be a little less
favorable Saturday especially the farther north you go. Expect a
trend not unlike today...with a little more vigorous "cloud
bubbling" across central/Southern Lower Michigan and perhaps a few
showers popping up south of M-72 with Lake Huron breeze improving
the probabilities over northeast lower. Outside of that...
however...overall Saturday shaping up to be a nice afternoon with
temperatures again mostly in the 70s with a few lower 80s.

Next short wave trough and attendant cold front expected to lie
across Western Lake Superior/western upper/northwest Wisconsin
Sunday morning. Some high clouds ahead of that may spread into
northern Michigan early Sunday morning...but the front will be slow
to move east during the day...and better dynamic support is trailing
the boundary. There is a narrow axis of 1.00+ inch precipitable
water values accompanying the boundary...but looks like a lot of
that will remain upstream during the day Sunday. 01/12z European model (ecmwf) likes
the idea of trying to spout another afternoon of convection across
interior northern lower...I don't like its dew points in the 60s by
Sunday evening. Bottom line is will keep a small chance for rain
across eastern upper Sunday...but dry below the bridge...then spread
rain chances southeast into lower Michigan Sunday night.

Medium range (monday/Tuesday/wednesday): weak height falls and
associated cold front slide through northern Michigan on Monday...
then slow/stall as it drops through Southern Lower Michigan and
northern portions of Illinois/Indiana/Ohio. Trend has been for a
further south push to the boundary with a small bubble of high
pressure settling in by midweek. So will continue with rain chances
across northern lower Monday as boundary settles south...and should
be able to push the dry Tuesday forecast along another day. The
farther south trend with the front also supports pulling back on the
rain threat for Wednesday.

Outlook (thursday/friday): trend toward improved weather for
Thursday with an increased potential for high pressure to hang
trough over the Great Lakes. Friday is more up in the air as
guidance has been showing poor consistency and flip-flopping between
runs...and certain to be more in the future. Surrounding office
consensus is to start Friday with a chance for showers/
thunderstorms...and will hitch along for the ride.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 101 PM EDT Friday Aug 1 2014

Persistence it is...with mostly VFR conditions in light lake
influenced wind regime. Cooling boundary layer tonight once again
should allow br/fog formation at kpln and kmbl...much like the
case the last few nights. Any IFR conditions at these sites should
quickly lift Saturday morning.


issued at 352 PM EDT Friday Aug 1 2014

No marine issues to be concerned with for several
days...well into next work week...with a light pressure
gradient...and afternoon lake breezes. Maybe an isolated shower
across NE lower each afternoon but threat for this is minimal at


Apx watches/warnings/advisories...



short term...msb
long term...jpb

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