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Area forecast discussion
National Weather Service northern Indiana
1230 am EDT sun Sep 15 2019

issued at 745 PM EDT Sat Sep 14 2019

A fast moving system approaching the upper Great Lakes will
provide a chance of showers and perhaps a thunderstorm early
Sunday morning, especially across southwest lower Michigan into
North Central Indiana. Afternoon highs on Sunday will be in the
upper 70s to lower 80s. Mainly dry weather is then expected for
the upcoming workweek.


Short term...(this evening through sunday)
issued at 239 PM EDT Sat Sep 14 2019

Perfect evening ahead with pleasant temperatures, low humidity
and no rain. Rain chances still look to increase late tonight into
Sunday as disturbance moving across the northern plains into the
Great Lakes will allow for increasing low level jet response and eventual
expansion or development of showers and storms across
Iowa/Wisconsin which will then build southeast reaching northern portions
of the area sometime after 10z, possibly as late as 12z. Hi res
models all agree on precip making it down but where the heaviest
occurs as well as how far south they remain split with either main
focus staying in Illinois where better low level jet influence will be, or from
Illinois into much of the forecast area here for the morning. Have
increased pops somewhat especially northwest and nudged timing up a bit.
Did go with some likely pops in the am in far northwest areas that will
have the best shot at this point. Will defer any further
refinements to overnight shift to monitor trends. Cloud cover and
precip will likely limit warming, but only minor tweaks to highs
for the moment on Sunday until we see how this pans out.


Long term...(sunday night through saturday)
issued at 239 PM EDT Sat Sep 14 2019

Frontal boundary will stall near the area with potential for some
lingering moisture and a small chance for some
sprinkles/drizzle/fog Sunday night into Mon am. Will have slgt
pops in to coordinate with nearby offices but confidence in
occurrence not overly great.

Strengthening upper level ridging will extend well north to the
Canadian border for the forecast period. Trough will move into the
western states for the start of the work week with a series of
waves trying to break down the ridge. For most of the week this
will likely be a futile attempt, but eventually as the weekend
approaches ridge may give enough for some chances for showers and
storms to enter the area. Until then, dry forecast appears


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1230 am EDT sun Sep 15 2019

Low level jet in association with SW disturbance shifting through
the nrn lakes aiding and abetting convection from cntrl/NE Iowa ewd
through NE Illinois along and within robust low level Theta-E ridge.
Expect this will continue to fester ewd with time W/previous
predicated thunderstorms in the vicinity mention adequate attm although did bump timing
toward daybreak.

Otherwise clearing/destabilization in wake of this activity will
likely yield renewed convection this evening invof kfwa where Theta-
E ridge overlaps tail end of advancing low level jet. Good cams
based clustering at least makes for a strong signal at this early
juncture yet will reaccess with later highres guidance/trends with
12z issuance. Nonetheless VFR expected through the period outside
outside a brief MVFR based vis restriction in thunderstorms.


Iwx watches/warnings/advisories...


short term...Fisher
long term...Fisher

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