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fxus63 kiwx 242338 
afdiwx

Area forecast discussion
National Weather Service northern Indiana
738 PM EDT Fri Mar 24 2017

Synopsis...
issued at 345 PM EDT Fri Mar 24 2017

A frontal boundary will drop south into the region bringing
increasing chances for rain to far Northwest Indiana and lower
Michigan tonight, and across the entire forecast area on Saturday.
Temperatures will remain on the warm side for most locations,
with lows generally in the 50s tonight and highs in the 60s to
near 70 degrees on Saturday. The one exception will be across
lower Michigan, far Northeast Indiana, and far Northwest Ohio on
Saturday where temperatures may hold steady in the 50s. The
occasionally wet weather will continue into Sunday with highs
ranging between the upper 50s and upper 60s.

&&

Short term...(this evening through saturday)
issued at 345 PM EDT Fri Mar 24 2017

Unseasonably mild with increasing rain chances tonight-Saturday...

Warm sector well established over the area this afternoon with ample
sunshine supporting deeper mixing. The result has been for stronger
wind gusts 30-40 mph and highs well into the 70s in deep layered
southwest flow.

Shortwave energy translating east through Ontario with high pressure
building in its wake will force the near sfc portion of a southern
WI-central Michigan front south to near the Lake Michigan shoreline in far NW
in/SW lower Michigan this evening/overnight...and the rest of our lower
Michigan/far NE in/far NW Ohio counties later tonight into Saturday. A
cooler marine influence to the north of this boundary will provide
a rather significant temp gradient making for a difficult/low
confidence temp forecast north of US 30 tomorrow.

Rain/embedded thunder chances will also increase in the vicinity
of this feature as the upper flow becomes increasingly diffluent
and deeper moisture advects in on a developing low level jet. This will
occur downstream of a Southern Plains low expected to wobble/fill
northeast into Missouri tomorrow. Continued to highlight lower
chances for scattered showers/iso thunder into far NW in/lower Michigan
this evening into the early overnight near the boundary, as
moisture quality at least initially looks a little suspect with
more widespread activity setting up north near the mid level
front. Better chances then into Saturday mainly along/northwest of
Hwy 24 as low level convergence/isentropic lift increases on the
nose of a low level jet.

&&

Long term...(saturday night through friday)
issued at 345 PM EDT Fri Mar 24 2017

Mild and at times wet pattern continues late weekend/next week...

The above mentioned upper low will continue to fill/open
northeast through the local area on Sunday. Residual
forcing/moisture along with some potential for weak sfc
destablization remains supportive of likely-categorical pops for
showers and perhaps some embedded thunder into Sunday. Upstream
kicker will force this wave northeast of the area by Sunday night,
though cannot rule out some lingering drizzle/light showers near
a leftover low level trough. The next in a series of Pacific
waves then brings the next chance for rain showers later Monday
into Monday night. This will be followed by slightly cooler/dry wx
for the middle of the week and then more rain chances Thursday-
Friday as the next impulse takes a track similar to this weekends
system.

&&

Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 718 PM EDT Fri Mar 24 2017

A difficult aviation forecast especially in near term at ksbn.
Classic Spring pneumonia front has moved south across Lake
Michigan and has passed through kbeh. Winds shifting to north and
becoming light or calm behind this front as much cooler and more
stable marine layer moves inland. Hires models showing this
boundary working through ksbn next few hours with wind shift to
north. Concerning is strength of southwest synoptic flow ahead of
this boundary and how far south and east it will make it with ksbn
currently right on southeast fringe of inland penetration. Put
Faith in these latest runs with a wind shift to north northwest
likely between 01z and 02z and winds decreasing to less than 10
knots. Boundary to remain in vicinity with shower development
then expected with warm air advection over cold dome and
increasing moisture and lift. Convective allowing models show a
more scattered nature to pcpn returns overnight. Fog development
with winds becoming light and increasing moisture also expected.
Thus restrictions to visible will be more of a combination of factors
rather than just shra and have stayed with previous thinking for
now. Kfwa to remain further away from front and lack of strong
forcing so kept them VFR until later Saturday afternoon.



&&

Iwx watches/warnings/advisories...
in...none.
Michigan...none.
Ohio...none.
Lm...Small Craft Advisory until 8 PM EDT this evening for lmz043-046.

&&

$$

Synopsis...steinwedel
short term...steinwedel
long term...steinwedel
aviation...Lashley



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