Office: BMX
FXUS64 KBMX 110538
AFDBMX
Area Forecast Discussion
National Weather Service Birmingham AL
1238 AM CDT Thu Aug 11 2022
.UPDATE...
For 06Z Aviation.
&&
.SHORT TERM...
/Updated at 952 PM CDT Wed Aug 10 2022/
Rest of tonight.
Lowered pops for this evening as convection is tapering down.
Some patchy fog will be possible toward sunrise as we near our dew
points. Lows look to be in fairly decent shape. I made a few
tweaks to hourly temps/dew points based on latest obs/hires
guidance, which changed lows only a degree or so generally.
08
Previous short-term discussion:
/Updated at 1248 PM CDT Wed Aug 10 2022/
Scattered to widespread showers and thunderstorms will be possible
this afternoon and evening...and again beginning Thursday morning
and lasting through the afternoon and evening. Today...a boundary
will be moving slowly to the southeast...located just north and
west of Marion and Lamar counties. This boundary will cause a
focus of convection to move across the northern counties...with
activity continuing through the early night. At the same time...a
sea breeze bringing thunderstorms will move north from the
Gulf across the southern half of the state. The rest of the area
will experience diurnal convection through the afternoon and
evening. Thursday will be a repeat of today...though the boundary
will have more of an influence as it slowly moves southeastward
through the state through the day.
Instabilities will range between 1500 to 2500 J/kg with PW values
above the climatological max for this time of year. Low levels are
very saturated...so the strong showers and any thunderstorms will
produce heavy rainfall limiting visibilities. With stronger
instabilities in the southern half of the state...closest to the
low level winds advecting moisture and warm air...will need to
watch for storms to become strong. Not anticipating any severe
thunderstorms at this time...but if one can tap into the energy
present and have enough lift...might see one develop.
Any storms that do move over the same areas...which would most
likely happen closer to the frontal boundary with the mid level
winds parallel to the boundary...localized flooding could be
possible.
Tonight...with low level moisture so high...fog development is
possible...though only kept in patchy fog mentioned in the
forecast for now. If the low level overcast clouds do
develop...fog development will be limited. Will keep an eye on any
updates. High temperatures today will be in the upper 80s to
lower 90s. Low temperatures tonight will be in the lower 70s. High
temperatures tomorrow will be in the mid to upper 80s.
24
.LONG TERM...
/Updated at 326 PM CDT Wed Aug 10 2022/
Guidance continues to show a front pushing southward through the
area on Friday, with the best rain coverage across the south
Friday afternoon. Lower rain chances and drier air are expected
through early next week.
14
Previous long-term discussion:
/Updated at 351 AM CDT Wed Aug 10 2022/
Friday through Tuesday.
The conclusion of an unsettled weather pattern is expected on Friday
as a relatively significant trough develops over the eastern CONUS
with a ridge remaining firmly entrenched over the Plains.
Strengthening northerly flow and southward moving high pressure will
push a front southward through Central Alabama. This will support a
strong gradient in rain chances on Friday, ranging from 20 percent
in our north to 80 percent in our far south. The advection of
noticeably drier air is expected during the weekend with isolated
showers and storms confined to the southern portions of Alabama.
Moisture quality could improve enough on Monday for a stray shower
or storm. Further increases in moisture and rain chances may occur
on Tuesday as the axis of moisture becomes aligned with the height
gradient between the trough in the eastern CONUS and ridge over the
Southern Plains.
87/Grantham
&&
.AVIATION...
06Z TAF Discussion.
The rain has ended across central Alabama with re-development expected
after 15z. Moist southerly low level flow will result in widespread
MVFR cigs between 10z and 14z with lcl IFR cigs. The cigs should
rise above 3000 ft agl by 16z. Numerous showers and sct tstms expected
after 18z, with lcl heavy downpours. The convective activity will
weaken after 00z, but sct showers and isolated tstms will linger
into Thursday evening.
58/rose
&&
.FIRE WEATHER...
High moisture content will remain in place across the region,
providing fuel for numerous afternoon and evening showers and
storms through Friday. Drier air and decreasing rain chances move
in from the north on Friday with lower RH values for this
weekend. 20 ft winds will remain below 7 kts, and out of the
south through Thursday, becoming northerly Friday. Minimum RH
values should remain above 50 percent each day through Friday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 87 68 89 64 89 / 70 50 20 0 10
Anniston 87 70 89 66 89 / 70 50 30 10 10
Birmingham 86 71 89 67 90 / 70 50 30 10 10
Tuscaloosa 87 71 89 69 90 / 70 50 30 10 10
Calera 86 71 89 68 90 / 70 50 40 10 10
Auburn 86 71 87 69 87 / 70 40 60 20 20
Montgomery 89 72 92 71 92 / 80 30 70 20 30
Troy 87 71 89 70 88 / 80 30 80 20 40
&&
.BMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Office: MOB
FXUS64 KMOB 110457
AFDMOB
Area Forecast Discussion
National Weather Service Mobile AL
1157 PM CDT Wed Aug 10 2022
.AVIATION...
06Z issuance...Numerous to widespread showers and storms gradually
develop through tomorrow morning over the southern portion of the
area then spread inland during the day. IFR to MVFR conditions
will accompany the showers and storms. Calm or light and variable
winds overnight become southeasterly 5 to 10 knots on Thursday.
&&
.PREV DISCUSSION... /issued 1055 PM CDT Wed Aug 10 2022/
NEAR TERM /Now Through Friday/...A longwave trough, currently over
the Great Lakes region, will quickly dive southeastward on Thursday
as an expansive upper-level ridge builds over the Rockies. With our
local area becoming sandwiched between these two features, flow
aloft will transition from light and variable on Thursday to a light
northerly flow by Friday. At the surface, the ridge axis from high
pressure over the Western Atlantic slips southward until it extends
across the Florida Peninsula and into the Gulf of Mexico. This will
allow for south to southeasterly winds to become more southwesterly
throughout the period. Additionally, a frontal boundary, associated
with the digging trough, will approach our region from the north and
start slowly pushing through the area on Friday.
Similar to the previous days, convection for both Thursday and
Friday will generally follow a typical diurnal cycle. For the rest
of tonight, lingering isolated showers and storms over portions of
our marine and coastal zones will start to increase in coverage
during the next few hours. Activity should begin pushing north of I-
10 around or a little prior to sunrise. With PWATs around 2.0 to
2.2 inches, convective coverage will become more widespread
(70-90% across the entire region) as storms push into interior
counties during the late morning and afternoon hours due to sea
breeze and outflow boundary collisions. Convection should taper
off into the late afternoon/evening hours as the environment
becomes worked over and instability drops off. For Thursday night,
model guidance suggests a surface convergence zone (possibly a
decaying outflow boundary from afternoon storms) setting up along
the coast, or just offshore. This should help initiate another
round of late night/early morning showers and storms, which will
work their way towards coastal counties, similar to what we see on
Thursday. Convective coverage will become numerous to widespread
during the afternoon hours as the cold front enters the region
and interacts with sea breeze and outflow boundaries.
The primary hazard for both Thursday and Friday will be slow-moving,
training bands of heavy rainfall, which could lead to localized
flooding concerns given the high PWATs and wet antecedent conditions
in place due to previous days of rainfall. A few stronger storms
capable of producing gusty downdraft winds also cannot be ruled out,
mainly for Friday as some drier mid-level air begins to push in,
allowing for DCAPEs to rise to around 700-1000 J/kg.
Temperatures for both Thursday and Friday will trend a bit lower due
to the higher convective coverage. Highs across the region will
generally be in the mid to upper 80s. Lows will be in the upper 60s
to lower 70s for northern counties and mid to upper 70s closer to
the coast. Lastly, a MODERATE risk of rip currents will continue
through Friday. /96
&&
.MOB WATCHES/WARNINGS/ADVISORIES...
AL...None.
FL...None.
MS...None.
GM...None.
&&
$$
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