973
FXUS64 KMEG 162359 AAA
AFDMEG

Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
659 PM CDT Fri May 16 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 633 PM CDT Fri May 16 2025

- A regional outbreak of severe thunderstorms is likely this
  afternoon into tonight with strong tornadoes, perhaps long
  tracked, damaging winds and very large hail.

- An Enhanced (3 out of 5) to Moderate (4 out of 5) Risk for
  severe weather is in effect across the northern half of the Mid-
  South this afternoon into tonight.

- Saturday will be mostly dry and warm.

- Scattered showers and thunderstorms will persist from Saturday
  night through the middle of next week with chances for severe
  storms each day, especially Tuesday.

&&

.DISCUSSION...
(This evening through next Thursday)
Issued at 214 PM CDT Fri May 16 2025

A significant severe weather outbreak is expected today. Storms
have already produced significant hail and damaging winds this
morning and minimal airmass modification in their wake. Tropical
humidity remains across the entire region with 70+ F dewpoints
within an increasingly warm boundary layer. Storms are expected to
fire later this evening both along and ahead of a cold front
positioned over OK/KS. These storms will head east, likely
congealing into a line with the potential for scattered
development out ahead.

Today`s environment is climatologically rare for the Midsouth in
late spring. A stout EML has been positioned over the region for
the past few days, containing 700-500 mb lapse rates into the 8
C/km range and continues to persist today. Surface insolation,
albeit muted under a thick cirrus shield, in conjunction with
these lapse rates will allow for MLCAPE of 3500+ J/kg this
evening. Upper wind fields are expected to contain a strengthening
mid- level jet streak during this time frame as well with the
Midsouth optimally positioned under the right entrance region.
Lift from this feature is expected to collate with peak heating,
significantly reducing capping. Surface convergence will be
somewhat nebulous this afternoon where a few renegade cells are
possible, but the highest confidence for storms is still with the
cold front as it passes through.

Once storms are able to form, they will find themselves within a
well-sheared environment with bulk shear in excess of 50 knots.
Low- level hodograph curvature will be lacking early on which
suggests a large (2"+) hail threat during the early evening. Very
cold 850-700 mb wet bulb temperatures could create strong cold
pools and a strong (75+ mph) damaging wind threat. As the evening
progresses, low-level hodographs are anticipated to enlarge with
both 0-1km and 0-3km SRH approaching the 200-300 m2/s2 range along
and north of I-40 suggesting a higher tornado threat. Storm mode
is still the largest question regarding the potential for
significant tornadoes this evening. If prefrontal supercells are
able to form, significant tornadoes are possible. Along the front,
initially discrete storms are expected to congeal into a line
with time. Tornadoes within this regime will be most likely while
storms are discrete before being undercut by strengthening cold
pools. Regardless, today has the potential to be a dangerous day
with an Enhanced (3 out of 5) Risk to a Moderate (4 out of 5)
risk for severe weather in effect across much of the region. Large
(2+ inch) hail, swaths of strong (75+ mph) straight line winds,
and the potential for strong tornadoes exists.

The cold front will continue south through the night, eventually
stalling somewhere over N MS. Temperatures should cool a bit
tomorrow with a few diurnally driven showers across N MS. A threat
for a few stronger cells containing marginally severe hail and
damaging wind is possible. This threat also exists Sunday as the
stalled boundary begins to lift north as a warm front in response
to a new trough moving east through the Western CONUS.

The western trough is expected to traverse the Central CONUS
Monday, reaching the Midsouth Tuesday. Another warm, tropical
airmass will be in place as this system approaches. Model guidance
continues to place a surface low over the Midwest with a cold
front moving through the region during the evening. Strong upper
flow will overspread a destabilizing airmass, resulting in another
chance for severe weather as outlined by the SPC. Specific details
on hazards and the magnitude of any severe threat are hard to pin
down at this time. However, at least a damaging wind and hail
threat are possible. Models currently struggle to produce the low
level SRH necessary for a widespread tornado threat, but some spin
ups could be possible within an organized line of convection. This
forecast is still several days out and will likely change through
the weekend. So, stay tuned for updates.

Ensembles are in good agreement with the upper flow taking a
northwesterly orientation through the end of the week after the
frontal passage Tuesday. Strong surface high pressure in
combination with this upper pattern will lock in colder air
through the end of the week. Highs are currently expected to
remain in the 70s and low 80s to end the period with mostly dry
weather.

&&

.AVIATION...
(00Z TAFS)
Issued at 658 PM CDT Fri May 16 2025

Though delayed, TSRA development is underway along a cold front
extending from west central to northeast AR. Additional isolated
TSRA development further south, will likely merge with the frontal
convection as we move through the evening.

The net effect is a slower arrival time of TSRA at MEM, and a more
linear convective mode, i.e., a broken line. The northern portion
of the line will be more progressive, and the orientation of the
line should extend from MEM to MKL around 05Z.

PWB

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&

$$

PUBLIC FORECAST...JAB
AVIATION...PWB