SPC MD 622
2024-05-03
SPC Mesoscale Discussions
MD 0622 CONCERNING SEVERE THUNDERSTORM WATCH 180… FOR SOUTHWEST KANSAS INTO NORTHWEST KANSAS
Mesoscale Discussion 0622
NWS Storm Prediction Center Norman OK
0828 PM CDT Fri May 03 2024
Areas affected...Southwest Kansas into northwest Kansas
Concerning...Severe Thunderstorm Watch 180...
Valid 040128Z - 040330Z
The severe weather threat for Severe Thunderstorm Watch 180
continues.
SUMMARY...Large hail and severe wind gusts remain possible even as
storms may tend to become elevated later into the evening.
DISCUSSION...KVNX/KDDC VAD profiles show an increase in the
low-level jet. The 00Z observed DDC sounding showed very steep
mid-level lapse rates though some capping was also present. Current
convection in WW 180 is expected to continue eastward with aid from
the low-level jet. The primary severe risk will exist with a storm
near the Wichita/Kearney County line. This storm will be capable of
hail up to 1.5-2 in. A line of storms is also moving east from near
Garden City to just west of Beaver, OK. This line has shown some
deepening cores on MRMS CAPPI and could produce severe wind gusts.
The overall eastern extent of the severe risk is not clear. However,
even as storms may become elevated with time, large hail and
isolated damaging winds could still occur. The tornado risk is
conditional on a discrete storm mode and should continue to diminish
as low-level stability increases. Some areal extension of WW 180
could be needed depending on convective trends over the next 2
hours.
..Wendt.. 05/04/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ICT...OUN...DDC...GLD...AMA...
LAT...LON 38680144 39000081 38999910 38689893 38069879 38049879
37999879 37279897 36849950 36660018 36540079 36620141
36700160 38680144
https://www.spc.noaa.gov/products/md/md0622.htmlSPC Mesoscale Discussions
SPC Day 3-8 Fire Weather Outlook
2024-05-03
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0401 PM CDT Fri May 03 2024 Valid 051200Z - 111200Z An active period of fire weather concerns remains likely beginning late this weekend and lasting well into the upcoming work week. The greatest fire weather risk will be focused across the central to southern Rockies and into adjacent areas of the central/southern High Plains where a dry air mass is already in place. Latest ensemble guidance continues to show strong agreement in the evolution of an upper-level trough (currently noted in water-vapor imagery over the northeast Pacific) as it translates east across the inter-mountain West and into the Plains Sunday and Monday, reaching the Great Lakes/northern Plains by Tuesday/Wednesday. Strong low to mid-level flow associated with this system will support multiple days of dry, windy conditions with an accompanying fire weather risk. ...D3/Sunday to D6/Wednesday - New Mexico and adjacent portions of TX/CO... Strong divergence aloft ahead of the approaching upper-level wave will support broad surface pressure falls across the central Rockies on Sunday afternoon. In response, southerly winds will increase across much of the Four Corners region into central and eastern NM. Latest mid-range ensemble guidance suggests sustained 20-25 mph winds will be common by late afternoon when RH values should be reaching their diurnal minimums between 10-20%. Although fuels across western NM are not overly dry as of Friday afternoon, dry/windy conditions on Saturday across this region should help cure finer fuels by Sunday. Perhaps the most intense fire weather conditions are anticipated on Monday afternoon across portions of east/northeast NM. The ejection of the surface low into the Plains Monday afternoon will support strong westerly downslope winds off the central/southern Rockies. This will maintain dry conditions across the region with 10-20% RH common. Elevated conditions are expected across a broad swath of the High Plains with critical conditions likely across much of eastern NM. Latest forecast guidance hints that 25-30 mph sustained winds are probable across northeast NM in the lee of the Sangre de Cristo Mountains. While this portion of northeast NM is currently receiving rainfall, such dry/windy conditions should yield dried grasses after a few hours. Persistent zonal flow will linger over the southern Rockies D5/Tuesday into D6/Wednesday. This will maintain a downslope flow regime with an attendant dry air mass (afternoon minimum RH values in the teens) across the southern High Plains with potential both days for elevated to critical fire weather conditions. The critical risk areas have been adjusted in this outlook update to reflect where medium to long-range ensemble guidance shows the strongest signal for sustained 20+ mph winds. These areas will likely be refined in subsequent outlooks as mesoscale details come into focus. Elevated conditions may linger into D7/Thursday across southern NM, but weakening gradient winds aloft should limit fire weather potential compared to previous days. ..Moore.. 05/03/2024 ...Please see www.spc.noaa.gov/fire for graphic product...
SPC MD 621
2024-05-03
SPC Mesoscale Discussions
MD 0621 CONCERNING SEVERE THUNDERSTORM WATCH 181… FOR PARTS OF SOUTH-CENTRAL NEBRASKA AND NORTH-CENTRAL KANSAS
Mesoscale Discussion 0621
NWS Storm Prediction Center Norman OK
0728 PM CDT Fri May 03 2024
Areas affected...Parts of south-central Nebraska and north-central
Kansas
Concerning...Severe Thunderstorm Watch 181...
Valid 040028Z - 040200Z
The severe weather threat for Severe Thunderstorm Watch 181
continues.
SUMMARY...An organized line of storms could produce 60-75 mph gusts
as it moves south-southeast.
DISCUSSION...An organized line segment has developed in western
Nebraska and moved southeast along moisture gradient. Measured
winds of 61 and 63 mph were reported near North Platte. Recent
surface observations from Holdrege, NE showed the dewpoint jumping
from 51 to 55 F in the last hour. Other ASOS/KS Mesonet observations
show upper 50s to low 60s F dewpoints that may try and push
northwestward this evening. Given the organization of the line and
the theta-e gradient, this activity will likely continue for the
next few hours with aid from the low-level jet. The observed 00Z OAX
and TOP soundings showed capping/low-level drier air making the
eastward extent of this threat uncertain. Wind gusts of 60-75 mph
appear possible with this line of storms. Small to marginally severe
hail may also occur, but should be more isolated given the linear
mode.
..Wendt.. 05/04/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OAX...TOP...GID...LBF...GLD...
LAT...LON 40320143 40890074 40950071 40859916 40689800 40489735
40249727 39939741 39559797 39509849 39679983 39900081
40320143
https://www.spc.noaa.gov/products/md/md0621.htmlSPC Mesoscale Discussions
SPC MD 620
2024-05-03
SPC Mesoscale Discussions
MD 0620 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR WESTERN NORTH TEXAS INTO ADJACENT SOUTHWESTERN OKLAHOMA
Mesoscale Discussion 0620
NWS Storm Prediction Center Norman OK
0727 PM CDT Fri May 03 2024
Areas affected...western North Texas into adjacent southwestern
Oklahoma
Concerning...Severe potential...Watch possible
Valid 040027Z - 040230Z
Probability of Watch Issuance...40 percent
SUMMARY...Ongoing convection across North Texas -- from west of
Childress to the Wichita Falls/Jacksboro/Mineral Wells vicinity --
may expand in coverage/intensity over the next couple of hours. New
WW issuance could become necessary, if convection can organize
further.
DISCUSSION...A cluster of northeastward-moving storms west of
Childress will soon exit Tornado Watch 178. Some model signal is
evident that the storms could persist -- and even grow upscale a bit
-- over the next couple of hours. The currently observed
environment -- mixed-layer CAPE near or exceeding 3000 J/kg -- would
certainly support this potential. While shear remains somewhat
modest, veering winds with height are providing ample shear for
mid-level updraft rotation. Additionally, other storms from near
Wichita Falls south to near Mineral Wells -- within generally the
same background environment -- have also maintained intensity.
We will continue to monitor convective evolution in the short term.
Signs of increased coverage or upscale growth of this convection
could warrant WW consideration.
..Goss/Guyer.. 05/04/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FWD...OUN...SJT...LUB...AMA...
LAT...LON 34120118 34810004 35129893 34949794 34469706 33629674
32589790 32609850 34120118
https://www.spc.noaa.gov/products/md/md0620.htmlSPC Mesoscale Discussions
SPC May 3, 2024 2000 UTC Day 1 Convective Outlook
2024-05-03
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Fri May 03 2024 Valid 032000Z - 041200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN A PART OF WEST TX... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH NE TO THE SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Giant hail, a few tornadoes, and severe wind gusts are possible over parts of west to central Texas through this evening. Scattered severe wind and hail are also possible over parts of the central Great Plains, mainly this evening into tonight. ...20Z Update... Across parts of west to central TX, initial supercell development is underway along the I-20 corridor between MAF/ABI. Despite modest lower-level shear, the large buoyancy and favorable elongation of the mid to upper portion of the hodograph should foster a few intense supercells. While left-splits will move northeast, slow-moving right-movers should progress south-southeast towards the Concho Valley per recent WoFS and early afternoon CAM guidance. Giant hail will be the primary threat with some upscale clustering into the evening promoting potential for significant severe wind gusts as well. Given the relative early initiation this afternoon relative to the nocturnal increase in the low-level jet, have refrained from higher tornado probabilities, although a sub-10% strong tornado risk remains evident. Across the south-central High Plains into southern NE, buoyancy recovery is well underway ahead of the lower-amplitude shortwave impulse cross the southern WY/northern CO portion of the Rockies. Primary change with this outlook is to increase the areal extent of the cat 2-SLGT risk somewhat to the east and south. This is driven by higher confidence in strong to isolated severe wind gusts accompanying multiple potential clusters and QLCSs evolving east from ongoing convection from the NE Panhandle to the Raton Mesa. ..Grams.. 05/03/2024 .PREV DISCUSSION... /ISSUED 1137 AM CDT Fri May 03 2024/ ...Southern Great Plains... Visible satellite imagery and morning surface analysis shows a very moist airmass across the Edwards Plateau northward to a residual effective boundary draped northwest to southeast across the TX South Plains into central TX. Near and south of the boundary, low-level moisture approaching the daily climatological maximum for several raob sites (reference 12z DRT, BRO, CRP) will contribute to a large moisture reservoir across west TX by mid-late afternoon. A north-south dryline intersecting the differential heating zone/residual boundary will help focus thunderstorm development later this afternoon/evening. Insolation through peak heating will contribute to very large to extreme buoyancy (3000-4000+ J/kg MLCAPE) across the Enhanced Risk area. The nose of a westerly 250-mb speed max (70-90 kt) will move into west TX later this afternoon/evening acting to elongate hodographs. Expecting heating and weak convergence in the vicinity of the aforementioned surface boundaries to contribute to a weakened cap by mid afternoon. Widely scattered to scattered storms are expected to develop through the early evening according to the latest model guidance. Large to giant hail (max size 3-4+ inches in diameter), a few tornadoes, and severe gusts are possible across the TX South Plains extending southeastward into portions of the Big Country. Depending on storm-scale interactions and local augmentation of the low-level wind profile, a strong tornado cannot be ruled out, but uncertainty at these scales precludes a delineated risk area. Some upscale growth into a severe cluster is expected across west-central TX this evening with severe gusts perhaps becoming the primary hazard late. ...Central Plains... No change in forecast thinking for a large hail/severe gust risk area across the central Plains. Though nowhere nearly as moist as the TX outlook area, a diurnally destabilized plume of moist advection should support a secondary relative max in severe potential along/ahead of the cold front and dryline from parts of eastern CO to western/northern KS and southern NE. Convection should develop by mid/late afternoon in a regional convergence maximum near and northeast of the surface low, with MLCINH weakened by favorable diurnal heating. Surface dewpoints in the 40s to low 50s F should be common, with steep surface-500-mb lapse rates, 500-1000 J/kg MLCAPE and well-mixed subcloud layers. Effective-shear magnitudes around 40-50 kt indicate potential for organized convection -- both in quasi-linear form near the front and initially discrete (but later merging upscale) off the dryline. Though activity will encounter a more-stable boundary layer with time and eastward extent across KS/NE, at least marginal severe-gust potential may last overnight as far eastward as parts of the Missouri Valley region.
SPC MD 619
2024-05-03
SPC Mesoscale Discussions
MD 0619 CONCERNING SEVERE THUNDERSTORM WATCH 179… FOR THE TRANSPECOS REGION OF WESTERN TEXAS
Mesoscale Discussion 0619
NWS Storm Prediction Center Norman OK
0627 PM CDT Fri May 03 2024
Areas affected...the Transpecos region of western Texas
Concerning...Severe Thunderstorm Watch 179...
Valid 032327Z - 040130Z
The severe weather threat for Severe Thunderstorm Watch 179
continues.
SUMMARY...Isolated severe storms continue to pose a risk for very
large hail and damaging wind gusts over portions of the Transpecos
region of western Texas.
DISCUSSION...Modest low-level moisture is indicated across parts of
the Transpecos region east of the dryline, which is supporting 1000
to 2000 J/kg mixed-layer CAPE. This has been sufficient -- in
tandem with the veering winds with height/ample shear across this
region -- to support development of isolated supercell storms
roughly along the Pecos Valley area.
The two most prominent storms -- one in eastern Pecos County and the
other near the Terrell/Crockett County line -- continue to exhibit
radar indications of very large hail production. Locally damaging
wind gusts are also possible with these storms, given the relatively
deep mixed layer. Storms will likely continue over the next couple
of hours, with potential for additional/isolated updraft
development.
..Goss.. 05/03/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 29890213 30700250 31540239 31650123 30680070 29220026
28750043 29190094 29890213
https://www.spc.noaa.gov/products/md/md0619.htmlSPC Mesoscale Discussions