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FXUS62 KCAE 142230

Area Forecast Discussion
National Weather Service Columbia SC
630 PM EDT Mon Oct 14 2019

A diffuse front lingering in the forecast area will become a
warm front Tuesday ahead of an approaching cold front. The warm
front will lift north of the area by Tuesday night. The cold 
front will cross the area Wednesday. The greatest moisture is 
forecast to be in the forecast area ahead of the cold front 
Tuesday night. Dry, seasonable weather remains in place through
the remainder of the work week. Warmer temperatures return for
the weekend with the next chance of rain towards the end of the
long term.


Latest analysis reveals the frontal boundary may have pushed through 
the Midlands as dewpoints have fallen across the region, also aided 
by mixing as satellite imagery indicates mainly sunny skies. 
Precipitable water values have dropped significantly with values 
at or below a half inch north of the I-20 corridor with a strong 
gradient to higher values toward the coast as high pressure builds 
in from the Tennessee Valley.

After the much needed rainfall overnight, no additional rain is 
expected through tonight with high pressure in place and the frontal 
boundary becoming diffuse or stalling to our south. Clouds will be 
on the increase later tonight as the next weather system develops 
over the middle of the country as an upper trough digs into the 
upper Midwest and moisture is pulled back northward ahead of it. 
Temperatures overnight will be impacted by the amount of cloud cover 
and this will be more noticeable in the southern Midlands and CSRA 
where clouds will arrive earlier and be thicker. Overnight lows 
expected to range from the mid 50s north to lower 60s south.


An upper trough over the northern Rockies will dig southeastward
Tuesday and Wednesday. At the surface, a frontal boundary 
located just east of the forecast area will lift northward as a 
warm front. Moisture will deepen on Tuesday from south to north 
with precipitable water values rising to 1.9 to 2.1 inches, 
which is 175 to 200 percent of normal. Widespread rainfall is
expected by Tuesday night across the area. The GFS pops have
trended down some for Tuesday. WPC has included portions of the
southeastern FA in its Day 2 marginal and slight risk of 
excessive rainfall outlook. Heavy rainfall will be possible at 
times. Conditions have been relatively dry across the area 
recently, which should mitigate the threat of flash flooding. 
Highs on Tuesday in the middle to upper 70s. 

A cold front will cross the area on Wednesday. The deeper 
moisture will push northeast of the area ahead of the frontal
passage. Scattered showers still seem reasonable. Most of the 
area should remain dry after 18Z. A much drier airmass will 
build into the region in the wake of the front late Wednesday. 
Precipitable water values will drop to less than half an inch by
03Z Thursday. Highs on Tuesday in the upper 70s to lower 80s.
Cooler air will work into the region Wednesday night with lows
in the middle to upper 40s.


High pressure will ridge into the region Thursday through
Saturday providing dry conditions. Temperatures on Thursday and
Friday will be much cooler than in recent days with highs in the
lower 70s. Good radiational cooling will promote overnight lows
in the middle to upper 40s. Moisture will return to the area
late Saturday and Sunday as an upper trough digs into the
Plains. The chance of rain will increase late in the weekend 
through early next week.


VFR overnight into Tuesday morning, then deteriorating conditions 
during the afternoon Tuesday and Tuesday night. 

Frontal boundary stalled to our south. Upper energy will roll 
eastward across the southern tier of states Tue/Tue nt, leading to a 
surface wave developing and moving east, ahead of which isentropic 
lift will spread rain into our region.  Some discrepancy in the 
models with regards to timing, but it generally appears that some 
light precipitation will move in during the morning, with 
precipitation becoming heavier and more widespread during the 
afternoon into Tuesday night.  Expect deteriorating CIGs/VSBYs in 
response, with the lowest restrictions after 00Z Wed.  

EXTENDED AVIATION OUTLOOK...Widespread rain and associated IFR 
conditions Tuesday night. Clearing Wednesday with breezy conditions 
in the afternoon. Dry conditions Wednesday night through Friday.



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