Tornado and Flash Flood in Alabama, June 6 to 8, 2019

Area Forecast Discussion
National Weather Service Birmingham AL
357 PM CDT Thu Jun 6 2019

.SHORT TERM...
Through Tonight.

Widespread light to moderate rain has moved through most of the
area today, with much of the more persistent rainfall now exiting
to the east. In its wake, cloud cover has decreased as drier mid
level air spread in the area. With the continued approach of
surface upper level lows, there is enough lift and instability
for scattered showers behind the exiting rain. Cannot rule out a
few lightning strikes as well. As the surface low rotates
northward through Mississippi and into southern Tennessee late
tonight, showers will increase in coverage overnight, with the
best chances across the northeast. Most of the area stand a 50-60
percent chance of additional rainfall through midnight.

14

.LONG TERM...
/Issued at 315 AM CT/

Friday through Thursday.

The very slow-moving vertically stacked low dips through the Mid-MS
Valley and over the Gulf States Friday. This will lead to synoptic
height falls, increased moisture with the southerly flow, and
therefore, higher rain and thunderstorm chances for Central AL.
Overall, I expect the showers and thunderstorms to be scattered in
nature at any one time. High resolution guidance suggests more
isolated cells vs. widespread stratiform precipitation. It will be
difficult to nail down exactly when it will rain/storm at any
particular location, but I feel confident enough that over any 6-12
hour period, most areas will see precipitation. Therefore, I have
continued mentioning 60-80% PoPs Friday and Saturday. There could be
a relative decrease in coverage overnight Saturday into Sunday, but
I'll keep at least 50% chance of rain/storms mentioned for now
because coverage will increase again for Sunday afternoon areawide.
This pattern continues through Monday before another trough swings
through the Great Plains, and slowly pushes the low pressure system
to our east Tuesday into Wednesday. Guidance continues to vary on
exactly when the rain/storm chances begin to taper, so I've held on
to at least a 20-30% for the eastern half of Central AL through
Tuesday afternoon. Temperatures during this time (Friday through
Tuesday) should remain in the low to mid 80s, though I would expect
quite a bit of variability based on when and where the rain develops
across the area. The main concerns for this system will be the
prolonged rainfall, which could lead to flooding concerns,
especially in poor drainage areas. PWATs remain on the higher end of
climatology, so some storms will likely be very effective rain
producers, capable of high rain rates. Confidence remains low in
just how much coverage these more convective storms will be, so I
will not add mention of flooding in the HWO at this time.

There's quite a bit of uncertainty in the forecast for Wednesday
into Thursday as the second main trough axis swings through the
area. Latest guidance suggests this will remain a drier system,
limiting any precip chances, but previous runs hinted at another
wave of rain Wednesday night into Thursday. I have included 15-20%
chance for rain/storms and will adjust once we have more run to run
consistency in the guidance.

25/Owen

&&

.AVIATION...
18Z TAF Discussion.

Periods of rain and MVFR cigs will continue across Central Alabama
this afternoon, with activity gradually becoming more scattered as
an initial area of widespread light to moderate rainfall pushes to
the north and east. As cloud cover also becomes more scattered,
thunderstorms will become possible. Stronger showers and storms will
produce heavier rain and lower vis. Scattered coverage will continue
overnight, with cigs lowering to at or below 1kft. Through the
period, winds will be from the southeast, up to 10kts.

14

&&

.FIRE WEATHER...

Extended period of wet weather will continue through the weekend,
with elevated rain chances each period. This, combined with high
RHs values should limit any fire weather concerns across the area.
Can't rule out low clouds and fog each morning in the next few
days as grounds become saturated.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     68  83  68  82  67 /  80  80  70  80  60
Anniston    70  83  69  82  69 /  80  80  70  80  60
Birmingham  72  84  70  83  69 /  60  80  70  80  60
Tuscaloosa  72  86  71  84  70 /  60  80  70  70  60
Calera      70  84  69  83  69 /  60  80  70  80  60
Auburn      71  82  69  81  69 /  70  80  70  80  60
Montgomery  72  87  71  85  71 /  60  80  70  80  60
Troy        71  85  71  84  70 /  60  80  70  80  60

&&

.BMX WATCHES/WARNINGS/ADVISORIES/...
None.

&&

Hazardous Weather Outlook
National Weather Service Birmingham AL
316 AM CDT Thu Jun 6 2019

ALZ011>015-017>050-071130-
Marion-Lamar-Fayette-Winston-Walker-Blount-Etowah-Calhoun-Cherokee-
Cleburne-Pickens-Tuscaloosa-Jefferson-Shelby-St. Clair-Talladega-
Clay-Randolph-Sumter-Greene-Hale-Perry-Bibb-Chilton-Coosa-Tallapoosa-
Chambers-Marengo-Dallas-Autauga-Lowndes-Elmore-Montgomery-Macon-
Bullock-Lee-Russell-Pike-Barbour-
316 AM CDT Thu Jun 6 2019

This Hazardous Weather Outlook is for the counties served by the
National Weather Service office in Birmingham.

.DAY ONE...Outlook through Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Activation of storm spotters and emergency management is not
expected at this time.