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Area forecast discussion 
National Weather Service northern Indiana
342 am EDT Friday Oct 24 2014

Synopsis...
issued at 1255 am EDT Friday Oct 24 2014

Friday into this weekend will feature mainly dry and mild
conditions. A couple of weak upper level disturbances will bring
an increase in clouds today and again Saturday morning. Highs on
Friday and Sunday are forecast to reach the upper 50s to middle
60s...with Saturday likely the warmest day with highs reaching the
middle to upper 60s.

&&

Short term...(today and tonight)
issued at 342 am EDT Friday Oct 24 2014

Fractured middle level trough/moisture axis with little/no reflection
in the low levels will translate east through the area this
morning/early afternoon. Associated weak support from a vorticity maximum
(showing up over Southern Lake Michigan on morning water vapor) and thinning
corridor of 850 mb moisture may be enough to generate a few spotty
light showers/sprinkles into mainly western portions of the forecast area
this morning...otherwise only impact will be slow eastward progression
of a broken/overcast low cloud deck. Modest height rises/subsidence in
wake of this weak trough should allow clouds to mix/scatter out a
bit later today...with afternoon highs expected to recover into the
upper 50s to middle 60s (dependent on cloud cover).

A rather strong shortwave and deepening surface low will emerge from a
Pacific northwest/SW Canada 150+ knots upper jet and track into Ontario and the
northern lakes by later tonight. The fold over of a more pronounced
low-middle level Theta-E ridge in advance of the system cold front will
result in a mild night for late Oct standards. Could also see isolated
showers/sprinkles and stratus develop late tonight given modest
925-850 mb warm air advection surge...although confidence/probability in any
measurable precipitation remains too low for a mentionable pop at this time.

&&

Long term...(saturday through thursday)
issued at 342 am EDT Friday Oct 24 2014

System of note for this period lies out near 140w this morning and will turn
inland along the West Coast early Sat. Downstream follow and perturbation
streaking through James Bay continues to oscillate in some degree amg
model solutions which as yet continues to yield some uncertainty in
regard to temperatures mainly Sunday. 00z suite as a whole much more
subdued west/backdoor cold front Sat night and indicate robust ll warm air advection developing
by afternoon. Thus in nod of gefs agreement and decided upward trend see
no reason to not bump sun temperatures up higher again.

West/progressive pattn aloft in place western system quickly amplifies northeastward
into central Ontario Tuesday as trailing sharp cold front bursts east. Ll
thermal ridge ahead of this ftr quite strong west/core of 16-18c 850 mb temperatures
nosing into the Southern Lake Monday. Even a conservative mix down from h9
portends addnl upward headroom likely and seems prudent to use
warmest guidance blend possible. Sig ll moisture/Theta-E surge within broad
low level jet west/western Gomex origins follows Monday night/Tuesday ahead of eastward surging
cold front. Given favorable Theta-E ridging lt Monday night and modest mass moisture
flux northwest third added a slight chance pop for rain showers west/thunderstorms and rain possible as whats
left of plains eml advts overhead. Otrws gist of prior Tuesday forecast
holds west/higher probability of precipitation warranted at least for western half in proximity to
tail end of greater glancing height falls.

Vigorous dry slot wraps eastward Tuesday night and cut probability of precipitation substantially
through evening and altogether late as frontal boundary is clearing the East
Coast at that time. Ridging and seasonably cool temperatures expected in wake
of this system Wed-Fri.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1255 am EDT Friday Oct 24 2014

Weak elevated trough/moisture axis across Illinois will spread slowly
east into northern in this morning. Ceilings will gradually lower to high
MVFR-low VFR around daybreak at sbn and late morning or early
afternoon at FWA before subsidence/drying likely scatters this
stratocu deck out by later in the day. Dry otherwise with light
south-southwest winds.

&&

Iwx watches/warnings/advisories...
in...none.
Michigan...none.
Ohio...none.
Lm...none.
&&

$$

Synopsis...steinwedel
short term...steinwedel
long term...T
aviation...steinwedel



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