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Area forecast discussion 
National Weather Service northern Indiana
359 PM EDT sun Aug 30 2015

issued at 142 PM EDT sun Aug 30 2015

A trough axis over the region will continue to weaken into
tonight. This feature will bring a low chance for showers and
thunderstorms to east central Indiana into Northwest Ohio through
this evening. Lows tonight drop back into the lower 60s...and
there is a chance for fog to redevelop. Highs on Monday will reach
into the lower to middle 80s. Next week will feature above normal
temperatures as high pressure builds in.


Short term...(this evening through monday)
issued at 355 PM EDT sun Aug 30 2015

Increased instability across eastern County Warning Area with sbcapes to 2000-2500
j/kg as surface T/dew point reach the middle 80s/upper 60s...hiest across far southeastern
County Warning Area. Focus for lift associated with weak trough passing through southeastern
half of County Warning Area this afternoon should aid in continued uptick in
convective development...though anticipate relatively meager
coverage given weak shear environment. Additionally southward moving middle
tropopause vorticy over southeastern Michigan per WV imagery to aid in general ascent
thi aftn/eve. Convection strongly tied to diurnal heat cycle with
marked downtrend in chances shortly after sunset.

Concern for br/fog and stratus development late tonight. Expansive
stratus/visibility reductions Neath upstream surface ridge/northwestern County Warning Area quite slow
in mixing today. Given weak/none surface flow overnight along with high
925mb relative humidity fields...stratus/br to likely expand in coverage again over
southern Great Lakes. 10-15 knots flow at 925mb should serve to
sufficiently mix blyr for stratus Blossom. Only slight chance probability of precipitation far
southern/southeastern County Warning Area associated with surface dps pooled to upper 60s/near 70 along
diffuse surface feature and possible peripheral vorticity /currently
across far western Kentucky/ swept into vorticity channel/into cntl in. Little change
with respect to for a cooler/drainage flow tonight along
Berrien Colorado shoreline/kbeh.


Long term...(tuesday through sunday)
issued at 355 PM EDT sun Aug 30 2015

Its looking to be a toasty week. The 500mb ridge over our area
continues to build through the long term period as a trough moves
into the western Continental U.S.. 850mb temperatures are expected to rise to 17-
20c...which puts temperatures in the upper 80s for inland locations.
Normal temperatures for the first week of September range from the
upper 70s to low 80s.

Uncertainty exists however about the chances for precipitation this
week. The Fly in the ointment is that there are a couple of weak
shortwaves aloft that models generate convection for Tue-Fri. In the
absence of any mentionable forcing associated with these waves...I
am hesitant to include any probability of precipitation at all...except Tuesday/Wednesday
when the strongest of these waves moves through. Have limited these
to slight chance...mainly in the afternoon. If anything does
develop...expect it to be isolated and non-severe. Otherwise...kept
conditions dry Thursday through sun...where slight chance of showers/T-
storms is possible in the west and central.

Added patchy fog to the forecast for late Monday night/Tuesday
morning given light winds and low level moisture.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 142 PM EDT sun Aug 30 2015

Light low level flow along with slow mixout across northern Illinois/northwestern in
lends difficult forecast with respect to br/stratus redevelopment
late in forecast period. By daybreak 10-15 kts coincident with
high 925mb relative humidity suggest that low clouds to likely reform around
08-10 UTC...especially in light of slow improvement seen upstream
today. Br/fog also a concern as well...espcly at ksbn with higher
xover temperature.


Iwx watches/warnings/advisories...


short term...Murphy
long term...Dodson

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