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Area forecast discussion 
National Weather Service northern Indiana
107 am EST Monday Nov 30 2015

issued at 106 am EST Monday Nov 30 2015

Mostly cloudy conditions can be expected overnight as an upper
level disturbance and low pressure area approach the region. There
is a chance of rain late Monday afternoon...mainly along and south
of US Route 30. Rain will overspread the entire area Monday night
before conditions begin to dry out again on Tuesday. Temperatures
will hold steady this morning...primarily in the upper 20s and
lower 30s. High temperatures on Monday will reach into the middle to
upper 40s.


issued at 727 PM EST sun Nov 29 2015

Trends from previous forecast left mainly intact. High clouds
still blanket most of forecast area this evening...although
showing signs of thinning across far northwest portions of the
area. Middle level clouds are expected to stream back into these
locations late evening/early overnight however as middle level warm
advection increases. Dry conditions expected to persist as axis of
better low level moisture advection/transport remain confined to
MS River Valley overnight. Min temperatures appear to be in good
shape...with mins expected to be reached late evening/early
overnight before leveling off...or perhaps slowly rising.


Short term...(this evening through monday)
issued at 149 PM EST sun Nov 29 2015

Main concern for the short term will be precipitation chances
Monday afternoon. Otherwise...we start out quiet this afternoon
and overnight with an amplifying ridge overhead and high pressure
at the surface. Meanwhile...closed 500mb low/associated surface
low pressure system moves into the plains by Monday afternoon.
This will bring weak 850-500mb qvector convergence and deeper
moisture/precipitable waters around 1.2 inches into mainly locations south of US
30 Monday afternoon. Think this may be enough for some light rain
chances. In the meantime...expect increasing cloud cover as the
surface low pressure system inches eastward. Temperatures should bottom
out in the upper 20s and 30s...coldest in the northeast. Shouldnt
be as cold as last night given increasing cloud cover.


Long term...(monday night through sunday)
issued at 149 PM EST sun Nov 29 2015

Closed low over the central rockies this afternoon will eject eastward and
open quickly across NE on Monday and northeastward into the northern lakes by Wednesday
morning. Attendant surface boundary stalled through the Tennessee Valley will
surge northward across the Ohio Valley Monday night/early Tuesday west/a period of rain
expected primarily lt Monday night. Otrws vigorous middle level dryslot will
envelop the area Tuesday and have cut probability of precipitation accordingly. Middle level trough
and attendant wrap around moisture shield then pivots eastward lt Tuesday
night/Wednesday am west/band of rain showers/shsn appearing more likely especially far
north downstream of favorable wrly follow lake enhancement. However given time
of day and marginal boundary layer thermal profile have again kept
west/mix mention west/little if any snow accumulation expected.

Surface ridging follows and expected to expand west/time over the Ohio Valley
west/dry and seasonable weather for the remainder of the period.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 102 am EST Monday Nov 30 2015

Focus primarily on deteriorating conditions late in forecast period.
An upper level cyclone will lift northeastward from the central rockies to
near ksux by the end of the forecast period. Meanwhile...latent
surface boundary across Tennessee Valley will surge northward with anticipatory
stratiform rain shield spreding into northern in. Also suspect ceilings to
lower even further from around 06 UTC into daybreak
Tuesday...near/just beyond current forecast period. Later forecast to
delve more into potential IFR conds developing late Monday night.


Iwx watches/warnings/advisories...


short term...mesoscale discussion
long term...T

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