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000 
FXUS63 KIND 240833
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
332 AM EST Sat Feb 24 2018

.UPDATE...
Long Term and Aviation Sections have been updated below.

&&

.SYNOPSIS...
Issued at 300 AM EST Sat Feb 24 2018

A frontal system is expected to affect the area through tonight. In 
the wake of this front, high pressure will move in for the early 
parts of next week. Another frontal system may affect the area 
around the middle of next week.

&&

.NEAR TERM /Today/...
Issued at 300 AM EST Sat Feb 24 2018

Radar indicates area of rain expanding across the area, ahead of a 
mid level wave currently moving through Missouri. Short term model 
guidance suggests this wave will move through the area later this 
morning after sunrise, and pass off to the east during the early 
afternoon hours.

Will continue with high PoPs through the midday hours today in 
association with the passage of the wave. The heaviest rain looks 
like it will occur after sunrise this morning, based on location 
and timing of the best lift. 

There may be a lull in the rainfall for a period later this 
afternoon as this wave departs, as model guidance suggests the next 
area of stronger lift won't begin moving into the southwest zones 
until close to sunset.

There is some concern for the axis of the heaviest rain shifting 
north with time, as the 850mb front moves north. Will therefore 
expand the Flood Watch a few counties farther north.

Low level thicknesses suggest the GFS MOS highs are probably a 
little on the cool side. Will bump up the highs a few degrees. 
Appears highs today probably won't be reached until sunset.

&&

.SHORT TERM /Tonight through Monday night/...
Issued at 300 AM EST Sat Feb 24 2018

Will continue with high PoPs tonight, as surface cold 
front/occlusion moves through in the 250500Z-250900Z time frame. 
Models suggest wind fields aloft will be quite strong, with a low 
level jet in excess of 65 kts, and a mid level jet around 100 kts, 
although lapse rates/instability continue to look rather poor. 
Potential exists for high winds and embedded circulations with any 
convection that develops near the front.

Rest of the short term looks dry, as high pressure builds across the 
Ohio and Tennessee Valley.

Progged low level thicknesses suggest the GFS MOS temperature 
guidance for the next couple of days looks reasonable, so only minor 
adjustments planned.

&&

.LONG TERM /Tuesday through Friday/...
Issued at 332 AM EST Sat Feb 24 2018

A somewhat zonal upper flow will occur across the U.S Tuesday and 
Wednesday as a short wave over the central U.S. deepens into a 
closed upper low over the southern Great lakes Thursday and southern 
New England Friday.  The GFS and Canadian models are in pretty good 
agreement on this scenario while the European indicates a less 
phased scenario with a weaker northern stream disturbance and a 
southern stream system.  Will lean more towards the GFS/Canadian 
solution with a stronger more phased solution.

High pressure over the eastern U.S. Tuesday will move on to the east 
as low pressure deepens over the plains Wednesday...moving into the 
southern great lakes Thursday and to the southern New England coast 
by Friday.  Tuesday will be dry and with low chance POPS late 
Tuesday night and Wednesday.  Wednesday night and Thursday will be 
wet as the low pressure area and a frontal system move through. 
Then dry most areas by Friday.  

Temperatures will be quite mild Tuesday through Thursday and a little
closer to normal by Friday. Went with highs in the upper 50s to 
lower 60s Tuesday and Wednesday...55 to 60 Thursday and 40s to around
50 by Friday.   Lows will be in the 40s Tuesday and Wednesday night 
and in the 30s Thursday night and upper 20s to near 30 by early 
Saturday.

&&

.AVIATION /Discussion for the 24/09Z KIND TAF Update/...
Issued at 332 AM EST Sat Feb 24 2018

Minor tweaks made to KIND TAF to better match current conditions.
No other changes are needed at this time.  Previous aviation 
discussion follows...

Poor flying conditions are expected for the duration of the TAF
period as widespread rainfall impacts the TAF sites. Conditions
will hover around the MVFR/IFR mark through the morning. However,
conditions will deteriorate even further to LIFR by Sun 00Z as 
rain intensifies. Meanwhile, winds will start out northerly, then 
veer to the southeast through the course of the TAF period. 
Sustained speeds will range between 5 to 11 kts, increasing late 
in the period. Low level wind shear will also be a threat late in 
the period as dynamics intensify.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Sunday morning for INZ045>049-051>057-
060>065-067>072.

Flood Watch through Sunday morning for INZ030-031-035>044.

&&

$$

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