Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/27/23
Area Forecast Discussion
National Weather Service Amarillo TX
613 PM CDT Fri May 26 2023
(This evening through Saturday night)
Issued at 229 PM CDT Fri May 26 2023
Potential for thunderstorms bringing the possibility of severe hail,
damaging winds, and flooding continues in the short term.
Today, latest ridge riding shortwave looks to potentially generate
another round of convection in NM which may spread into the western
Panhandles this evening into the overnight hours. Similar to
yesterday, effects of the extensive morning convection have
temporarily stabilized the atmosphere across the Panhandles, as
evidenced by the abundant but flat cumulus, particularly in the
east, where subtle subsidence on the back side of last night`s
shortwave is favored. Due to aforementioned stabilization, expect
the bulk of today`s thunderstorms to once again occur after 7pm.
Best bet for generation looks to be a remnant outflow boundary from
last night`s MCS, somewhat apparent as a thin line of agitated
cumulus in NE NM. Have once again leaned heavily on the HRRR given
the good performance of this guidance yesterday and the trend toward
a later start time in line with expectations based on observational
data. On the whole, expect less overall coverage compared to
yesterday given the issues with destabilization.
With a trend toward stronger winds aloft, expect a bit more wind
shear compared to yesterday, with 0-6km bulk shear values in the 30-
40 knot range as MLCAPE once again builds into the 1000-2000 J/kg
range. Resulting long hodographs are mostly straight however, so do
expect some splitting supercells and subsequent upscale growth as
the evening goes on. Given these parameters, hail and damaging winds
once again look to be in play, with a bit higher of a top end hail
risk compared to yesterday, which featured paltry shear. Finally,
given the later start time and the expectation for splitting
supercells, the tornado risk appears very low. Flash flooding will
once again be a big concern given our climatologically high
antecedent rainfall and expected storm motions around 25 mph.
Saturday, as the main upper trough to our west finally begins to
move eastward, next notable shortwave looks to arrive during the
earlier afternoon. Thus, expect a more typical afternoon initiation
time unless convection overachieves Friday night. Upper level winds
look to be more modest with resulting deep shear struggling to
surpass 25 knots. Thus, only expect lower end severe hail and winds,
with flooding issues returning to the forefront given crawling
favored storm motions.
(Sunday through next Thursday)
Issued at 248 PM CDT Fri May 26 2023
Sunday, main portion of the current western upper trough finally
shifts eastward. Yet another shot at afternoon through nighttime
showers and thunderstorms will result as moisture remains broadly
supportive. Flooding concerns look to be the primary concern with
any thunderstorms Sunday, as upper winds aloft take another small
step downward, resulting in paltry shear and sluggish storm motions.
That said, instability alone would be supportive of a stray severe
hail report, so cannot rule out severe thunderstorms.
Monday and Tuesday look to feature a relative respite from our
active weather pattern as a weak upper ridge builds over the
southern High Plains. That said, cannot rule out additional
convection each day as southerly flow at the surface helps maintain
sufficient moisture for a couple thunderstorms.
Wednesday and Thursday, High Plains upper ridge breaks down as our
next round of western troughiness takes over. While presence and
magnitude of severe and flooding risks will depend on each day`s
details, at this time Thursday could feature some more notable
severe thunderstorms as some guidance does favor more robust winds
aloft compared to what we`ve seen recently.
Issued at 606 PM CDT Fri May 26 2023
A somewhat messy TAF period is in store with the chances of
thunderstorms to continue across the combined OK/TX Panhandles.
VFR conditions to start could diminish to MVFR with broken CIGs
just under 3k ft going into the hours of darkness. If a terminal
is impacted by a thunderstorm some brief IFR conditions may be
possible. Have mostly stayed positive with timing and conditions
of impactful weather for each terminal. However, amendments may
very well be needed through the 00Z TAF period.
.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX 59 72 58 77 / 70 60 40 30
Beaver OK 59 76 58 79 / 30 50 40 30
Boise City OK 55 72 55 79 / 60 40 30 30
Borger TX 61 75 60 81 / 50 60 30 30
Boys Ranch TX 59 75 58 81 / 70 50 30 20
Canyon TX 58 71 57 78 / 70 60 40 40
Clarendon TX 60 72 58 74 / 50 60 50 50
Dalhart TX 56 72 54 78 / 70 40 30 30
Guymon OK 58 74 57 79 / 50 50 30 20
Hereford TX 58 72 57 79 / 60 50 40 40
Lipscomb TX 60 75 58 77 / 20 50 40 40
Pampa TX 59 72 58 76 / 40 60 40 30
Shamrock TX 60 74 58 75 / 30 40 40 40
Wellington TX 62 77 60 75 / 30 50 50 50
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
1021 PM CDT Fri May 26 2023
Issued at 1016 PM CDT Fri May 26 2023
Strong low level moisture transport pointing into a surface trough
that coincides with thunderstorm outflow is maintaining convective
activity from north central to southwest North Dakota late this
evening. Excessive rainfall from training convection remains a
concern, though radar suggests a decreasing trend in rainfall rate
intensity over the past hour. The main area of concern is from north
central Dunn to northeast Billings Counties, where a narrow band of
3 to 6 inches of rain has been estimated by MRMS. A secondary area
that has not received as much rain but where some moderate rain
continues to fall is across southern Ward County. Due to the
rainfall rates becoming less intense, there is only a very low
probability for any flash flooding to develop through the remainder
of this event. But ponding of water in urban and low lying areas is
certainly remains a potential impact. Though some CAMs have already
begun dissipating the convection too quickly, the moisture transport
is forecast to make a slight tilt to the east later tonight, which
should allow showers and storms to diminish.
UPDATE Issued at 726 PM CDT Fri May 26 2023
At 7 PM CDT, a surface trough was located from Bottineau to Golden
Valley Counties and slowly advancing east. Numerous pieces of
shortwave energy ejecting off higher terrain to our south and west
will promote showers and thunderstorms from western into north
central North Dakota this evening into the overnight hours. Early
evening activity is likely to remain tied to the surface boundary.
Training convection may cause localized areas of flooding,
especially from near Killdeer to Minot where MRMS has already
estimated pockets of 2 to 4 inches of rain. Cell mergers and
boundary collisions may briefly cause storms to pulse near severe
limits, but the overall threat of severe weather is low and will
likely continue to diminish through the evening as MLCIN
.SHORT TERM...(This Evening through Saturday)
Issued at 151 PM CDT Fri May 26 2023
The main forecast issues in the short term period include winds
over the east for the rest of this afternoon and early evening,
and thunderstorm chances and severe potential west and north
central later this afternoon and tonight.
Currently, surface low pressure was situated over southeast
Saskatchewan with a cold front through northwest and portions of
west central ND. A strong southerly flow was situated over central
and eastern North Dakota. Winds over eastern portions of central
ND are near advisory criteria, with a few obs up into low
advisory, but given the small areal extent and low end criteria,
will hold off on an advisory. Will take a last look before
publishing. It will be windy though over eastern portions of
central ND through the afternoon.
The focus then shifts to the west later this afternoon and
tonight. Currently, MLCape values are are around 500-1000J/KG just
ahead of the aforementioned cold front (north central ND) and back
south southwest through western ND and into northwest SD. Shear is
not real strong over this area, with 20-30 knots of effective
shear over northwest and north central ND. There are some strong
low level lapse rates over much of western and central ND,
especially just ahead of the cold front (there is also an area of
congested CU development over the far south central attim) Mid
level lapse rates are pretty meager however, and based on the EMC
RAP analysis, are not forecast to increase much over western and
central ND this afternoon/evening. Thus it seems like the best
chances for severe weather later this afternoon/this evening would
be right along/ahead of the cold front from north central into
west central ND. Later tonight convection over the northern High
Plains could poke into the far southwest, but the threat would
seem to be pretty limited by then. Also, late tonight there could
be some convection over the south central along the nose of a
developing low level jet. This also looks to be uncertain given
the limited instability aloft. However a stronger storm or two
over either of these two areas can be completely ruled out.
On Saturday we see another warm day with highs generally in the
80s. Will discuss Saturday`s convection in the long term section.
.LONG TERM...(Saturday Night through Friday)
Issued at 151 PM CDT Fri May 26 2023
Overall, the general synoptic setup changes little on Saturday,
with a slight shift eastward in the marginal severe weather
threat. Latest CAMS are hinting at convection moving into western
ND early Saturday evening, so daytime May not be too eventful
storm wise. However, whether convection hold off until then, or
starts earlier, there is a broader area of 1000-2000J/kg of CAPE
and perhaps some slightly better shear over the western third of
ND. A few strong to severe storms will be possible Saturday night.
At this time we will stick with the 60 mph winds and quarter size
hail, but depending on how things develop Saturday, threats could
be a little higher than this.
Sunday and Monday, the threat shifts more over central ND as the
western upper trough finally pushes into the region.
A unique and stagnant pattern still looks to set up for the work
week next week. Each day will have ample moisture and instability
to work with. The zonal flow followed by a shift back to southwest
flow could also provide weak disturbances at times. The overall
result will be chances for showers and thunderstorms almost each
day through the week. The surface gradient does not look to be as
sharp as this week, thus strong winds are not expected at this
time, although some breezy winds may return later next week.
Temperatures will also remain warm through next week and generally
in the 80s for highs and 50s to 60s for lows.
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 1016 PM CDT Fri May 26 2023
Thunderstorms will continue to impact KMOT into the early
overnight hours, with visibility falling to IFR levels at times.
The storms should gradually diminish at KMOT after 06Z. Additional
storms are still possible at KXWA later tonight, but the
probability there has decreased. A few showers and possibly a
thunderstorm are also possible at KBIS later tonight. A period of
drier weather is expected for all terminals Saturday morning and
into the afternoon, but another round of thunderstorms is likely
across western North Dakota by Saturday evening. Southerly winds
will become stronger once again on Saturday. The probability of
low-level wind shear criteria being reached tonight at KJMS has
decreased, but a 25 kt difference between the surface and 1-2 km
above the ground with a slight directional shift is still
Area Forecast Discussion
National Weather Service Cheyenne WY
529 PM MDT Fri May 26 2023
.SHORT TERM...(This evening through Saturday)
Issued at 345 PM MDT Fri May 26 2023
Today is the first day of a potentially active weekend across the
area. Earlier, a Severe Thunderstorm Watch was issued across the
region, encompassing all counties in the CWA with the exception of
Carbon County. Currently, convection is ongoing across Carbon and
Albany Counties and is expected to expand further eastward into far
eastern Wyoming and the Nebraska panhandle by later this afternoon
and into the evening hours. The more favorable environment for
severe storms exists east of the Laramie Range, so this is where the
strongest storms are expected. Dewpoints in the 50s, steep 700-500
mb lapse rates, and MLCAPE values of 1000 to 2000 J/kg will likely
trigger severe convection later today. Although shear values are
modest with 0-6 km shear of 20 to 25 kts, storms to the south of our
CWA already look to be producing severe weather. Initial threat will
most likely be large hail with more discrete cells. During the
evening, storms look to transition to a more linear mode, which
will lead to more of a wind threat. Storms looks to vacate the CWA
by midnight tonight.
Heading into the weekend, the severe weather potential continues. A
Rex Block parked over the eastern part of the country will keep an
upper-level trough near stationary over western CONUS. Daily
precipitation chances will be likely as the CWA sits under the
downstream side of the trough. Saturday looks as though it will be a
repeat of today with severe storms possible in the same area. Model
soundings from the RAP and GFS indicate similar conditions with
dewpoints in the 50s and 60s, steep 700-500 mb lapse rates, and
MLCAPE around 1500 J/kg. 0-6 km shear values are better at 25 to 30
kts. Hi-Res models also seem to hint at the potential for storms
tomorrow to be a bit stronger than today, but perhaps not as
widespread in coverage. Again, initial threat looks to be hail in
discrete cells, but transitioning to a wind threat as convection
turns to more linear clusters of storms by the evening hours.
Model soundings continue to indicate PW values above climatology
with moist low-levels. This will mainly lead to a heavy rain
Because of the Rex Block, severe storm chances look locked in place
through at least Sunday. Severe storm threat for Sunday looks the
greatest in the Nebraska panhandle where dewpoints stay in the 50s
and instability looks strongest. However, storm coverage on Sunday
looks much less and more scattered compared to today and Saturday.
The upper-level trough shifts slowly eastward, pushing the better
plume of mid-level moisture further off to the east over central
Nebraska. This will lead to a bit of a drier day across the CWA with
less numerous storms.
.LONG TERM...(Saturday night through Friday)
Issued at 225 PM MDT Fri May 26 2023
Monday...Although a low amplitude ridge aloft will lie across
Colorado, it looks like a shortwave trough aloft will be moving
across our counties near peak heating, and will combine with
adequate low and mid level moisture to produce scattered afternoon
and evening showers and thunderstorms mainly along and east of
Tuesday-Friday...With a longwave trough aloft over the Great Basin
states and southwest flow aloft over our counties ejecting various
shortwave troughs, along with adequate low and mid level moisture to
fuel thunderstorms, we will be in a favorable pattern for scattered
afternoon and evening showers and thunderstorms, most numerous
Wednesday through Friday when moisture will be more plentiful.
Temperatures will be moderated by the widespread late day cloudiness
and precipitation coverage.
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 523 PM MDT Fri May 26 2023
Wyoming TAFS...As a weather disturbance moves near the region,
isolated thunderstorms will be in the vicinity until 02Z this
evening with scattered to broken clouds from 5000 to 10000 feet
AGL. Thunderstorms will also be in the vicinity at Laramie and
Cheyenne after 18Z on Saturday, when broken ceilings from 5000 to
10000 feet will occur. Sufficient pressure gradients will produce
wind gusts to 32 knots at all terminals until 02Z, and to 25 knots
after 15Z Saturday.
Nebraska TAFS...As a weather disturbance moves near the region,
occasional thunderstorms will occur through 03Z producing wind
gusts to 40 knots along with visibilities from 3 to 4 miles and
ceilings around 3500 feet AGL. From 07Z to 15Z, ceilings will be
near 2000 feet AGL, then improve to 5000 feet after 15Z. Winds
will gust to 35 knots through the forecast period.
Issued at 225 PM MDT Fri May 26 2023
Minimal fire weather concerns continue over the next several days
due to daily chances for showers and storms and fuels in green-up
status across the area. Widespread storms with wetting rains are
likely on Friday and Saturday. Storms may contain strong gusty winds
with gusts in excess of 60 MPH. Conditions will gradually dry out
Sunday into the beginning of next week with minimum RHs across the
area falling into the 20s and teens by Tuesday.
Issued at 330 AM MDT Fri May 26 2023
Warm temperatures continue into the holiday weekend, leading to
additional snowmelt runoff in areas where substantial snowpack
lingers, mainly above 9000 ft. Minor flood stage continues to be
reached each morning along the Little Snake River near
Baggs/Dixon. Forecasts from the RFC show this continuing for
Friday and Saturday, but crests may potentially fail to reach
minor flood stage by Sunday. Will continue to monitor through the
weekend. The latest forecasts continue to show the North Platte
River near Saratoga remaining below flood stage, so the Flood
Watch was cancelled yesterday. The river remains at action stage.
Action stage has also been reached on the Encampment River, and
could be reached by Monday on the Laramie river in Laramie.
Forecasts do not show flood stage being reached on either river at
Daily chances for afternoon showers and thunderstorms continue
this weekend. Slightly faster storm motion is expected Friday and
Saturday, but substantial atmospheric moisture will continue to
produce a locally heavy rainfall threat. Most of this should stay
Area Forecast Discussion
National Weather Service Wilmington NC
1002 PM EDT Fri May 26 2023
Strengthening low pressure off the Georgia coast will move
inland across the Carolinas Saturday bringing gusty winds and
heavy rain, especially along the coast. Some drier air will
arrive Sunday. After a cool holiday weekend, more seasonable
temperatures will return next week.
After reviewing the latest HRRR and ensemble heavy
precipitation probabilities, we`ve issued a Flash Flood Watch
for the three coastal Cape Fear counties in NC through 9 PM
Saturday evening. Widespread rainfall amounts of 3-5 inches will
likely have mesoscale enhancements producing streaks of 7+
inches of rain by this time tomorrow evening. Given significant
rainfall that occurred in this area a week ago, soils are not
nearly as dry here as they are in other parts of the eastern
We`re also continuing to monitor storm surge anomalies which
have not changed over the past three hours. It appears
tonight`s high tide will pass without coastal flooding
Earlier updates from 730 PM follow...
Radar and surface obs reveal the shield of isentropic rain is
spreading onshore as deep and moist easterly winds overrun
colder and drier air in place at the surface inland. Although
dry air inland is eroding/evaporating the western periphery of
radar echoes across the Pee Dee region, it`s only a matter of
time before rain reaches the surface here.
High res models continue to paint a variety of positions and
intensities of precip maxes associated with convective
enhancement within the broader zone of overrunning precipitation
Saturday. The potential for flooding rain is low most places,
except a little higher across Brunswick and New Hanover counties
where soils are a little wetter and HREF probs for 6+ inches
show a relative maximum. If higher certainty in large rainfall were
to appear with 00z models I could see a small Flash Flood Watch
for this area.
Changes made with this update include raising PoPs and sky
cover to 100 percent for all areas late tonight and Saturday and
changing the precip type descriptor to "rain" rather than
"showers" tonight. Wind speeds both inland and offshore are
verifying nicely and need no changes.
Tide gauges at Wrightsville Beach and Myrtle Beach show a storm
surge anomaly of +1.4 to +1.7 feet currently. Given that we`re
in between the new and full moon it will take a much larger
surge of at least +2.4 feet to produce coastal flooding during
tonight`s high tide. I`ll keep an eye on those gauges through
the evening but don`t anticipate we`ll need to issue an
.NEAR TERM /THROUGH SATURDAY/...
Digging shortwave off the west coast of FL will work in concert with
a second shortwave along the SC coast to create significant weather
impacts during the next 24 hours. The shortwaves are aiding low
pressure developing along a front stalled off the FL coast this
afternoon. This low will wobble off the FL/GA coast tonight before
starting to move north-northwest Sat morning. Meanwhile, high
pressure continues building in from the north, with the pressure
gradient growing ever tighter. Winds will continue increasing this
afternoon into tonight as the low slowly strengthens. Gusts in
excess of 50 mph will be possible across the coastal waters with a
brief period of time where gusts may approach 50 mph along the
immediate coast. However, no plans for a wind advisory given that
forecast speeds end up short of meeting criteria. Farther away from
the coast peak gusts overnight into Sat will be on the order of 35
to 40 mph.
Light to moderate showers, currently along the coast, will gradually
spread inland this evening. Forecast soundings continue to depict
low and mid-level dry air inland until around midnight. It may take
until then for the I-95 corridor to start seeing any rain of
significance. However, coastal areas will start to see moderate to
heavy rain much sooner. Precipitable water rises from 1.3-15." this
afternoon to over 1.7" by daybreak Sat. Meanwhile the freezing level
will also be increasing, growing the warm cloud layer by close to 2k
ft by midday Sat. The abundant moisture and the deep warm cloud
layer will translate to high efficiency when it comes to rainfall
production. Any cells will be capable of producing very heavy rain
and with the combination of low level convergence along the coast,
isentropic lift and dynamics as the low approaches, there will be no
shortage of forcing mechanisms. Periods of heavy rain overnight and
Sat could lead to rainfall in excess of 6 inches in some coastal
areas with inland areas pushing 3 inches in some places. If showers
and any isolated thunderstorms manage to train over the same
location in quick succession flooding could become a concern.
Lows tonight will range from below normal near the coast to well
below normal inland. The slow northward movement of the low late
tonight should prevent a scenario with temps rising along the coast
in the pre-dawn hours. Highs on Sat will be well below climo with
daytime temperatures in some inland areas struggling to hit 60
degrees as the wedge holds on. Closer to the coast highs will be in
the upper 60s to lower 70s.
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
The main focus for this forecast period will be the
last stage of the area of low pressure meandering offshore and
finally moving inland. There is still a lot of uncertainty of where
it moves inland but overall the speed seems to have slowed down thus
significant rainfall remains possible at least for a few more hours.
Mid level dry air and decreased forcing will lead to more scattered
pops early Sunday. Once again progress to the north will be slow
thus we don`t go with a dry forecast until Monday morning. With the
cold air wedge long gone, temperatures will bounce back somewhat
moreso Sunday with highs in the lower to perhaps the middle 70s.
Lows will be in the 55-60 degree range.
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A mid level low, which will have closed off in the
Tennessee Valley this weekend will meander to the east with a brief
Rex block developing and basically dissipating through the period.
There really is no cleansing feature at the surface or aloft. Chance
pops remain in place mainly during the afternoon and evening hours
but do trend down as the mid level low finally drifts further enough
offshore to become a non factor. Temperatures will drift back to
near normal values.
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions will begin to degrade as soon as 04z along the
coast as rainfall rates increase and cloud bases lower. There is
a high potential MVFR conditions will develop at all three
coastal airports (KILM, KCRE, and KMYR) no later than 08z,
spreading inland to affect KFLO and KLBT before 12z Saturday.
Conditions will degrade further Saturday as widespread moderate
to heavy rain brings IFR ceilings and a moderate chance for
periods of IFR visibility. Precipitation will become more
showery after 18-20z when there will be a low to moderate
potential for thunderstorms along the coast. With the exception
of cool temperatures, the effects from this system will be
similar to a weak tropical system with synoptic wind speeds
increasing to 20G30 kt from the north and northeast.
Extended Outlook...There is a high potential for lingering MVFR
to IFR ceilings Saturday night through Sunday as showers
continue to circle the weakening low pressure inland. Convection
should become more scattered in nature Monday and Tuesday will a
low to moderate potential for sub-VFR conditions.
Treacherous marine conditions continue through Sat with northeast
winds in excess of 30 kt sustained and potential for brief period of
gusts approaching storm force, especially across portions of the SC
waters. Seas already over 6 ft will keep building, likely exceeding
10 ft this evening and potentially approaching 15 ft in places. Low
pressure off the FL/GA coast this evening will slowly move north
late tonight into Sat. The gradient will start to relax as the low
moves closer, with winds dropping below gale force in the afternoon.
An SCA headline will be needed once the gale is dropped for both
winds and seas and the SCA may potentially be needed for an
additional 18 to 24 hours.
Saturday Night Through Wednesday...
Winds and seas will be on the decline Saturday evening as
low pressure moves inland and weakens. It seems a Small Craft
Advisory will be necessary at least through about midday Sunday. The
headline will be issued later Saturday as the Gale Warning takes
precedence. For the remainder of the period which includes much of
next winds will be weakly forced and driven somewhat by the sea
breeze taking turns with the synoptic flow. Significant seas will be
For beach hazards, a High Surf Advisory for 5-9 feet breakers is in
effect for north of Cape Fear through Saturday due to high waves
associated with the low. There is potential for dune erosion at east-
facing beaches with tonight`s high tide. High rip current risk is
forecasted north of Cape Fear today, and forecasted for east-facing
beaches Saturday Sunday, along with strong north to south longshore
current. Elevated rip risk at south and southeast facing beaches
possible over the weekend. Conditions will improve further late
Sunday into Monday.
Unseasonable chilly air on the west side of the coastal low is
threatening records for the coldest daily high temperatures at
several locations. Here`s the list:
Coldest Observed Daily High Temps on Record
Location Fri May 26 Sat May 27
Wilmington NC 60 in 1972 64 in 1961
Lumberton NC 66 in 1963 *60 in 1972
N. Myrtle Beach SC *68 in 1963 65 in 1961
Florence SC 66 in 1972 *66 in 1961
* indicates this record is threatened
SC...Beach Hazards Statement from 6 AM EDT Saturday through
Saturday evening for SCZ054-056.
NC...Flood Watch from 6 AM EDT Saturday through Saturday evening
High Surf Advisory until 8 PM EDT Saturday for NCZ106-108.
High Rip Current Risk from 6 AM EDT Saturday through Saturday
evening for NCZ106-108.
MARINE...Gale Warning until 2 PM EDT Saturday for AMZ250-252-254-256.
Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
659 PM CDT Fri May 26 2023
Issued at 221 PM CDT Fri May 26 2023
Tonight and Tomorrow...
A surface low stationed over the Lower Miss Valley will help
initiate light rain chances across the north this afternoon through
this evening along and north of the HWY 82 corridor. Though there
is ample amount of dry air across the region, as this low tracks
E/NE, moisture will wrap around and when met with peak heating,
light rain will be possible. The rest of the region today has and
will remain dry through tonight. Mostly clear to partly cloudy
skies will prevail this evening with lows near seasonable values.
Expect temperatures in the 60s area-wide.
The previous mentioned low will continue to deepen across the Mid
and Deep south Saturday. While there won`t be a lot of flow at
the surface, there will be some flow aloft along with cooler
temperatures aloft. With the lack of surface instability, severe
weather is not expected however, during the afternoon and early
evening hours storms and rain chances will be possible across
north- central and northeastern areas of the region. It is worth
the mention that the 12z HRRR sounding model indicated a inverted
V with deep high vertical totals. Meaning any storms that have a
chance to become surface based could produce gusty winds. High
temperatures will be in the 80s Saturday across the region. /JNE/
Saturday night through next Friday...
A broad upper level low propagating from the southeastern region
into the mid-Atlantic coast will push out of the lower Mississippi
Valley by Sunday. This will filter drier and warmer low level air
into the ArkLaMiss region through the weekend into mid-week. Weekend
highs will remain in the lower to upper 80s, while overnight lows
range in the upper 50s to middle 60s.
By mid-week, an upper low spinning up off of the Texas coast,
progged to make its way into the Lower Mississippi Valley by
Wednesday will supply the next possibility for rain chances. An
influx of southerly flow and instability will allow for isolated
to scattered showers and storms Wednesday and Thursday afternoon.
These storms are expected to be diurnal in nature, so
precipitation chances should decrease by the early evening.
Temperatures will be warmer, with highs in the upper 80s to low
90s, while lows remain in the middle 60s to low 70s. /AJ/
Issued at 656 PM CDT Fri May 26 2023
VFR conditions with winds generally out of the northeast less than
10 kts should prevail at all TAF sites through the period.
Isolates SHRA or TSRA are possible before 02Z Saturday and again
after 19Z Saturday, but confidence in impacts to any TAF site was
too low to mention at this time. /NF/
.PRELIMINARY POINT TEMPS/POPS...
Jackson 62 84 61 84 / 10 20 10 0
Meridian 60 83 58 84 / 0 10 10 0
Vicksburg 64 85 61 86 / 10 30 0 0
Hattiesburg 62 85 61 87 / 0 0 0 0
Natchez 64 85 62 86 / 0 20 0 0
Greenville 64 83 61 84 / 20 30 0 0
Greenwood 64 82 60 83 / 20 40 10 10
...Update to aviation forecast discussion...
Issued at 242 PM CDT Fri May 26 2023
- Warm temperatures continue this weekend into next week
- Mainly afternoon/early evening chances (10-30%) of showers and
thunderstorms Sunday through Thursday
19Z water vapor imagery depicts broad low pressure over the eastern
US and another upper trough over the west, leaving ridging over the
central CONUS. Sfc high pressure is centered over WI and MI and
extends into northeast KS. A diffuse boundary can be seen along a
line from Emporia to Manhattan to Washington, with diurnal cumulus
having developed west of that boundary and clear skies remaining
east of it. While a few of the 12Z CAMs are still trying to develop
isolated shower and storm activity in north central KS this
afternoon, the HRRR and RAP have backed off on this potential with
the better instability still well to our west. Would expect most, if
not all, locations to stay dry for today. The influence of the sfc
high should keep mainly clear skies around tonight, allowing for
temperatures to fall back to the 50s for most, perhaps upper 40s in
far northeast KS. Heading into Saturday, models prog the upper low
in the southeastern US to retrograde slightly while lee sfc
troughing deepens in the eastern Rockies. Still, precipitation is
favored toward western and central KS with locations within the CWA
staying dry. Highs look similar to today in the 80s area-wide.
Precipitation chances improve somewhat into early Sunday as the lee
trough moves a little closer to the CWA, although large-scale
forcing for ascent still looks weak. This will remain the case
through much of next week as the main upper trough stays out west
with weaker perturbations being ejected out of that trough to bring
10-30% chances for showers and thunderstorms each day through
Thursday. This type of set-up brings low predictability in regard to
timing and placement of precip associated with these waves, and will
likely need to take it day by day, but at this time storms look to
be mainly diurnally driven. There are signs of the upper ridge
starting to break down late in the week, and details on that should
become more clear in the coming days. Temperatures look to hold
steady with highs in the 80s, warming about a degree or two each day
in the forecast period with low 90s in some locations by mid-week.
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 555 PM CDT Fri May 26 2023
VFR conditions will continue. Dry air moving in from the east has
pushed crossover temperatures below even the coldest low
temperature forecast from guidance, and with some boundary layer
mixing returning, the chance for any diurnal ground fog are very
low despite modest winds and clear skies.