Severe Thunderstorm Warning 83, NWS Atlanta, GA

Area Forecast Discussion
National Weather Service Peachtree City GA
417 AM EDT Mon May 23 2022

...Wet, unsettled pattern expected to clear by the weekend...

.SHORT TERM /Today through Tuesday/...
A hybrid low-pressure system is forecast to move through the
northern forecast area this morning, bringing widespread rains to
the forecast area for the first time in a while for some local
spots. We describe the system as 'hybrid' because it sits on the
dividing line of true tropical, warm-core, symmetric low pressure
systems, and mid-latitude cyclones which exhibit more cold-core,
asymmetric properties. This low-pressure system is supported by a
weak, upper-level trough, but the surface low-pressure is the more
dominate organizing feature located in the warm, moist sector of a
broader synoptic system. The low also has an organized rain shield
on its right-front quadrant with an associated low-level jet of 30-
35kts between 850-700 hPa but doesn't appear to have associated
frontal/baroclinic zones.

Either way, several waves and bands of showers and thunderstorms are
expected throughout the morning and into the early afternoon with
the low center expected to push through North Georgia this
afternoon. A Marginal risk for severe storms will be possible, in
part due to a strong low-level jet which could enhance the northern
outflow of water-loaded downdraft regions in any stronger storms
that develop in organized bands of convection.

In the wake of this low pressure system, the environment will remain
in a warm, moist airmass, with cloudy skies and deep moisture with
PWATs over 1.6 inches and some weak instability. A plume of enhanced
PWATs near 2 inches may be a catalyst for further storm development
in the afternoon along a pseudo-frontal boundary, but placement of
this boundary and intensity of any shower/storm development is yet
to be determined.

A brief break in the precip is expected overnight, but by tomorrow
scattered sporadic clusters of showers and thunderstorms will
return. These conditions will occur as an amplifying Rossby Wave
train amplifies over the eastern and central CONUS with strong south-
southwesterly flow over the Southeastern US, setting up an active
pattern headed into the long term. Further bands or weak-meso lows
could organize convective development tomorrow as well, but no where
near the same extent of the system passing through the area today.

Thiem

.LONG TERM /Tuesday Night through Sunday/...
Extended period kicks off with persistent, moist air mass
positioned over the Southeast as it gets caught in the periphery
of the high pressure ridge to the east, and a progressive trough
to the west. As the low traverses the Plains and approaches the
region Thursday afternoon, the combination of the anchored ridge
and reinforcing southerly flow will keep anomalously high
precipitable water values near 2 inches over the state. Diurnal
showers and thunderstorms are expected Thursday, with better
coverage in the afternoon and evening, but not fully shutting off
overnight. QPF is highest over far north Georgia where orographic
lift and better moisture will support periods of heavy rainfall.
In this area, rainfall totals of 2 inches or more are possible,
with generally 1-1.5 inches generally along and north of the fall
line, and 0.3 to 0.5 over the southeastern zones. An experimental
Day 4 Slight Risk of Excessive Rainfall from WPC includes portions
of northeast Georgia and will continue to be monitored.

Recent dry conditions should prevent widespread issues from the
heavy rainfall, accumulations through the short term period could
prime portions of the state for more of a response. At this time,
flooding risk still appears limited.

Models continue to show some promise ending the precipitation by
Friday afternoon as parent low lifts to the northeast and surface
front pushes east and south across the state -- just in time for
the holiday weekend. Behind the front, northwestly flow and high
pressure at the surface will keep dry conditions in place through
Sunday, with mild temperatures through the week returning to the
mid to upper 80s by Saturday.

LGB/31

&&

.AVIATION...
06Z Update...
Chaotic aviation fcst through the TAF period with several waves
of potential SHRA/TSRA possible. Initial wave of RA in fcst area
from 06-18Z, with SCT SHRA/TSRA coverage from 18Z through 03Z.
Lower MVFR/IFR CIGs/VSBYs expected in north and western areas
through most of the TAF period starting around 10Z. Overnight CIGs
expected to lower once again to IFR/LIFR levels at ATL/AHN/CSG
sites. Lowered VSBYs likely with heaviest rains. Winds expected
to start out of the east with gradual shift clockwise through the
period, and fcst to go east to west at ATL around 17Z.

//ATL Confidence...06Z Update...
Medium confidence on precip coverage/timing after 15Z.
Medium confidence on IFR/MVFR timing.
High confidence on all other elements.

Thiem

&&

.PRELIMINARY POINT TEMPS/POPS...
Athens          79  64  81  63 /  70  70  50  50
Atlanta         77  65  81  66 /  80  50  50  40
Blairsville     71  59  78  60 /  90  50  50  50
Cartersville    76  62  83  64 /  80  40  50  40
Columbus        80  66  85  67 /  70  50  50  30
Gainesville     75  64  81  64 /  80  60  50  50
Macon           85  66  86  65 /  70  50  50  30
Rome            77  61  84  65 /  80  30  40  40
Peachtree City  78  63  83  64 /  70  50  50  30
Vidalia         89  69  89  68 /  60  50  50  30

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...Thiem
LONG TERM....31
AVIATION...Thiem

Hazardous Weather Outlook
National Weather Service Peachtree City GA
417 AM EDT Mon May 23 2022

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
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Baldwin-Banks-Barrow-Bartow-Bibb-Bleckley-Butts-Carroll-Catoosa-
Chattahoochee-Chattooga-Cherokee-Clarke-Clayton-Cobb-Coweta-
Crawford-Crisp-Dade-Dawson-DeKalb-Dodge-Dooly-Douglas-Emanuel-
Fannin-Fayette-Floyd-Forsyth-Gilmer-Glascock-Gordon-Greene-
Gwinnett-Hall-Hancock-Haralson-Harris-Heard-Henry-Houston-Jackson-
Jasper-Jefferson-Johnson-Jones-Lamar-Laurens-Lumpkin-Macon-
Madison-Marion-Meriwether-Monroe-Montgomery-Morgan-Murray-
Muscogee-Newton-North Fulton-Oconee-Oglethorpe-Paulding-Peach-
Pickens-Pike-Polk-Pulaski-Putnam-Rockdale-Schley-South Fulton-
Spalding-Stewart-Sumter-Talbot-Taliaferro-Taylor-Telfair-Toombs-
Towns-Treutlen-Troup-Twiggs-Union-Upson-Walker-Walton-Warren-
Washington-Webster-Wheeler-White-Whitfield-Wilcox-Wilkes-
Wilkinson-
417 AM EDT Mon May 23 2022

This Hazardous Weather Outlook is for portions of North and Central Georgia.

.DAY ONE...Today and Tonight...

Isolated to scattered thunderstorms are possible through this
evening. Some storms may be strong to severe and capable of
producing gusty winds, locally heavy rainfall and frequent
lightning.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday...

There is a chance of thunderstorms each day from Tuesday through
Friday. Some of the storms each day may be strong and capable of
producing gusty winds, frequent lightning, and locally heavy
rainfall.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected through tonight.