Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/22/23
Area Forecast Discussion
National Weather Service Cheyenne WY
530 PM MDT Wed Jun 21 2023
.UPDATE...
Issued at 1254 PM MDT Wed Jun 21 2023
An all-hazards severe weather event, including large destructive
hail, damaging winds, and a few tornadoes, remains possible
this afternoon throughout much of southeast Wyoming and western
Nebraska.
As of 19z, several mesoscale features are becoming apparent as we
begin to zero-in on heightened risk areas in today`s event.
Abundant moist upslope flow is apparent in surface obs over nearly
all of western Nebraska and southeast Wyoming, with a 61 degree
dew point recently observed at KCYS. At the surface, a pseudo-
dryline boundary is continuing its retreat westward into the
Laramie Basin, with a 50 degree dewpoint and southeasterly winds
observed last hour at KLAR. This boundary, while no longer evident
on radar, is still discernible on satellite as it retreats
underneath a developing cumulus field west over the Snowy Range
foothills and eastern Shirley Mountains. Convective initiation
appears imminent within the next hour in these locations, per
agitation on latest GOES Day-Cloud-Phase satellite imagery and the
uncapped atmosphere depicted on latest RAP surface analysis. One
or two dominant cells may emerge along this boundary, which is
supported by a highly consistent run-to-run signal in CAM
guidance. 40-50+ knots of bulk shear, curved hodographs with
sufficient mid-level flow, and southeasterly inflow will support
supercellular storm modes. Therefore, a heightened threat of
large to extremely large hail, and a tornado risk, is possible
over Albany, Platte, and northern Laramie counties over the next
few hours.
Farther east, abundant upslope stratus cloud cover is locked-in
over the I-25 corridor north of Cheyenne. The result has been a
stable airmass throughout eastern Platte county, Goshen, Converse
and Niobrara counties in Wyoming and points eastward in northwest
Nebraska. If current trends continue, the severe weather threat
may be greatly delayed in these areas until this cloud cover can
erode. Any dominant supercells that emerge from the Laramie Basin
will likely continue through the Laramie Range, but may ultimately
weaken as they approach the I-25 corridor in this scenario. If
stratus can erode and surface heating can commence, supercells
with a large hail and tornado threat may be able to continue east
of the I-25 corridor. Will continue monitoring trends this
afternoon in this area.
Finally, in far southwest Nebraska, capping has eroded and
severe thunderstorms have commenced. 2" hail has already been
reported with a transient, southwest-drifting supercell over KSNY.
Flow aloft is not as fast in this area, with only 25-40 knots of
bulk shear as a result as opposed to 40-55 knots farther north and
west of the Laramie Range. Therefore, a more chaotic storm mode
is expected for now over southwest Nebraska and possibly even
eastern Laramie County Wyoming as storms drift west-south-westward.
With such abundant surface moisture in place (Tds AOA 65 degrees)
and small but still curved low-level hodographs in place per CAM
guidance, any dominant cells that can maintain some discrete
nature will still pose a large hail threat as well as a brief
tornado threat. The tornado threat in southwest Nebraska/SE WY
will be locally enhanced near any cells that interact with
surface boundaries/outflows that have developed over the course
of the afternoon.
&&
.SHORT TERM...(Today and tonight)
Issued at 320 AM MDT Wed Jun 21 2023
Main forecast concern today surrounds the potential for severe
thunderstorms for southeast WY and western NE with multiple
hazards in play including large hail, damaging winds, heavy
rainfall leading to potential flash flooding, and tornadoes
possible.
Currently, latest satellite and radar imagery shows a cold front
positioned north of KCYS that has begun to stall out as low
stratus and fog has developed along the I-80 corridor out to
Sidney. KCYS dropped to 1/4 mile earlier, but seems to be bouncing
back up to 2 miles with similar observations at KSNY and KIBM.
Expecting patchy fog to continue early this morning across
southeast WY through the southern NE Panhandle. Southwest flow
aloft continues with the upper level low to the northwest with
passing shortwave disturbances in the flow across the Rockies
today that will lead to lee cyclogenesis and continued near
surface moisture advection with southeasterly flow bringing mid-60
dew points to western NE and possibly cross in the WY border. An
inverted trough extending northward from CO will lead to a
convergence boundary setting up across the NE Panhandle later
today that will be one focal point for CI in addition to the
Laramie Range. The overnight SPC Outlook update did introduce a
5% tornado probability area east of Cheyenne extending up to
southern Goshen Co and into portions of the southern NE Panhandle.
Steep mid-level lapse rates exceeding 8 C/km ahead of the
shortwave over top of the moist boundary layer will lead to
1500-2000 J/kg MLCAPE developing along the higher terrain by mid-
afternoon. Low level moisture boundary looks to be strongest along
the Laramie Range from Chugwater up through Douglas so could see
a few storms develop here moving east-northeast with 45-50 kt of
0-6 km shear leading to potential severe storms. CAPE profiles
will be largest along the North Platte River valley from Wheatland
through Torrington and Scottsbluff, especially with a lot of
positive area in the hail growth zone (-10C to -30C) leading to
the potential for large hail through the early evening. Surface
easterlies with the Chugwater cyclone will enhance low level SRH,
but looks to be best in the early evening as 700mb flow increases
leading to 0-1 km SRH values climbing above 200 m2/s2. This will
lead to potential tornado development, especially with more
discrete cells whose inflow is not contaminated by colder surface
air from nearby storms.
Now shifting back east, the other area for potential CI will be
near the stalled front/convergence boundary over the NE Panhandle.
CAMs have been hinting at surface northwesterlies across the
northern Panhandle with surface southeasterlies farther south that
could lead to further moisture pooling near the North Platte River
valley. This will lead to near 3500 J/kg of MLCAPE developing with
shear profiles (mainly due to good directional change) well
capable of supercellular structures. While hi-res guidance is not
all in agreement on successful CI before 23z in this area, any
discrete cells that develop in this environment will be capable of
significant large hail with around baseball size possible.
Additionally, hodograph curvature with 0-1 km SRH values
approaching 100 m2/s2 and increased surface vorticity in the
presence of the stalled front could lead to tornado development
late this afternoon. Another hazard to consider will be heavy
rainfall and flash flooding as 1-hr FF guidance for these areas in
1-1.5 inches and Bunkers right-mover motion looks to only be 10
kt over the NE Panhandle.
Ultimately, initially discrete cells will become more widespread
leading to cold pool organization and MCS development in the early
evening through midnight. CAMs are very mixed on the exact locations
of convection today, but all solutions seem to end with a line of
storms propagating eastward through late tonight. While severe
hail will still be possible, this will most likely cut off the
potential for large hail and mostly transition to a damaging wind
threat along with heavy rainfall with possible flash flooding.
tl;dr
Severe thunderstorms likely this afternoon and evening across the
area. Be weather aware this afternoon and have multiple ways to
receive warnings!
.LONG TERM...(Thursday through Tuesday)
Issued at 320 AM MDT Wed Jun 21 2023
Forecast still on track. Severe storms are the primary concern for
Thursday and Friday. Followed by a possible high wind event Friday
night into Saturday.
Lingering showers and storms look like a good bet Thursday morning
as upper trough slowly moves east into central Nebraska. Shortwave
ridge moves through fairly quickly Thursday morning with the ridge
axis located along the Kansas/Colorado state line...north into the
Panhandle into western South Dakota by 18Z Thursday. Surface
frontal boundary looks to lay along a line from Denver to Laramie
to Rawlins Thursday afternoon. Begin to see some upper level
energy from the southwest. GFS soundings continue to show a
capping inversion around 640mbs for areas east of the front. Still
forecasting MUCAPE around 2000 J/KG with 0-6km shear around 35kts.
SPC has a Slight Risk area for severe thunderstorms for
Laramie...Albany and southern Platte and Goshen Counties with a
Marginal Risk area out into the Panhandle for Thursday. Will need
to see if overnight stratus breaks up in time for convection
initiation. Could be seeing stratus all day that would limit
convection significantly.
A day 3 Slight Risk for the Panhandle into
Platte/Goshen/Converse/Niobrara Counties for Friday. Friday looks
to be the more significant day for severe thunderstorms as MUCAPE
back up into the 3000J/KG range with 0-6km shear up near 50kts for
Sidney. Mid level capping inversion is wiped out after 18Z
Friday...as upper level low moves through the area.
Strong winds still being advertised on the GFS for Friday night
into Saturday. Closed low pressure system tracks across Montana
Friday night into Saturday. GFS 700mb winds up to 55kts over the
south Laramie Range. Don`t see too many high wind events this time
of year...but we could certainly see one during this timeframe.
Winds begin to ease after 15Z Saturday. Associated cold front
with the northern low passage moves into the CWA Saturday
afternoon and through the CWA into Colorado Saturday evening.
Wet pattern continues for Sunday into next week as we see
disturbances moving through the flow on a daily basis.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 521 PM MDT Wed Jun 21 2023
Wyoming TAFS...Moist low levels and a weather disturbance will
produce scattered thunderstorms through 02Z at Laramie and
Cheyenne with visibilities reduced to 2 to 3 miles and ceilings
near 2500 feet AGL. Otherwise ceilings will range from 7000 to
9000 feet AGL through the evening. Expect fog to develop at
Cheyenne from 08Z to 14Z with visibilities near 2 miles and
ceilings around 500 feet AGL. Ceilings will improve to 4000 to
6000 feet AGL at all terminals by late morning. Sufficient
gradients will support wind gusts to 35 knots until 03Z, and to
25 knots after 15Z Thursday.
Nebraska TAFS...Moist low levels and a weather disturbance will
produce scattered thunderstorms until 03Z producing wind gusts to
45 knots, visibilities down to 2 miles and ceilings near 2500 feet
AGL. Ceilings will lower to 500 to 700 feet AGL late tonight with
areas of fog and visibilities to 2 miles. Ceilings of 3500 to 6000
feet AGL will prevail from mid morning onward.
&&
.FIRE WEATHER...
Issued at 320 AM MDT Wed Jun 21 2023
Widespread showers and thunderstorms expected today along and
east of the Laramie Range. Wetting rainfall will be likely,
especially across the NE Panhandle through tonight. Showers and
thunderstorms likely again Thursday and Friday, but drier air will
work its way into south-central WY Friday and through the
weekend. Additionally, gusty winds will lead to elevated fire
weather conditions across much of Carbon County through at least
Sunday.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
UPDATE...MAC
SHORT TERM...MB
LONG TERM...GCC
AVIATION...RUBIN
FIRE WEATHER...MB
Area Forecast Discussion
National Weather Service Fort Worth TX
635 PM CDT Wed Jun 21 2023
...New Short Term, Aviation...
.SHORT TERM... /NEW/
/Through Thursday Evening/
An upper level disturbance has kicked off a round of convection
this afternoon across parts of North and Central Texas. A capping
inversion around 700mb had kept a lid on things until around 2
PM, after which a few strong to severe storms were able to
develop. The strongest storms have now become somewhat organized
into a small convective complex, which will pose a severe wind
threat for another hour or so as it pushes southeast through the
far southeast counties. Severe Thunderstorm Watch 353 is in
effect until 11 PM to account for this storm complex, but will
likely be cancelled for our counties before then as activity
exits to the south. Thankfully, those who received rain also
received a break from the oppressive heat. With the expectation of
additional showers and storms over the next couple of days, all
heat products will be allowed to expire at 8 PM.
The next round of storms will arrive late this evening, as an MCS
dives south through western Oklahoma within the northwest flow
aloft. This system will likely reach the northwest corner of the
CWA around midnight or so tonight. As has been the case for the
past month, large discrepancies within high-resolution model
guidance has created some uncertainty regarding the extent of the
overnight convection. The HRRR along with the Texas Tech WRF
continue to back off the eastern extent of this MCS, likely due to
a strengthening overnight capping inversion, and keeps all storms
well west of the I-35 corridor. A few other CAMs are more
aggressive and indicate the MCS reaching both the Metroplex and
much of Central Texas overnight. Will keep slight chance POPs as
far east as I-35, with the better chances remaining off to the
west. The main concern with these storms will be strong winds as
the complex pushes into a moist and unstable airmass. That threat
will be highest along and west of Highway 281, with the threat
decreasing the farther east you go.
With a mid level ridge remaining centered over Mexico, northwest
flow aloft will remain in place on Thursday. Additional
thunderstorms will be possible as another weak disturbance drops
southeast across the area. The best storm chances will start in
the mid to late afternoon hours during peak heating, and should
peak in the early evening hours as storms attempt upscale growth
into one or more clusters. A threat for large hail and damaging
winds will exist once again, along with locally heavy rain and
frequent lightning. Thunderstorm outflow and increased
clouds/precipitation should eliminate the need for any heat-
related headlines.
30
&&
.LONG TERM... /Issued 208 PM CDT Wed Jun 21 2023/
/Friday and Beyond/
With the upper ridge shifting to the southwest, northwest flow aloft
may help usher in overnight convection Thursday night into Friday
morning. This "ring of fire" pattern will be around Friday night
into Saturday morning as well and bring another round of overnight
convection. Strong to severe storms are possible with large hail
and damaging winds as the primary threats. Along with the
possibility of welcomed rainfall, this upper-level pattern also
brings temperatures down closer to normal values for the region as
we close out the work week.
Over the weekend, the ridge will build and shift eastward over our
area again, which will raise temperatures to around the century
mark. Fortunately, dewpoint temperatures are not expected to be
nearly as high as they have been so far this week, and that forecast
will keep apparent temperatures from going too high. That being
said, we will likely have conditions that warrant head advisory
issuance by early next week.
By Monday, a cold front will approach the Red River and may bring
some relief, albeit small, from the heat. However, it is not
expected to push too far into North Texas, and even those who do see
the front pass will only experience minor temperature drops.
Otherwise, dry, hot conditions will be around next week as well.
Schroeder
&&
.AVIATION... /NEW/
/00Z TAFs/
Storms which affected the Metroplex earlier have pushed south,
and may affect KACT for another hour or two. A lull is expected
this evening, then additional storms currently forming in the TX
Panhandle will affect mainly western portions of DFW TRACON
overnight. Storms could be just close enough to warrant VCTS from
04-08Z in the Metroplex, then 07-11Z at KACT.
The atmosphere may be initially worked over by outflow, but should
destabilize enough to allow for additional convection Thursday
afternoon. Will begin VCTS at 23Z Thursday for the Metroplex
TAFs, but may be beyond this forecast period for KACT.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 76 92 75 92 78 / 40 20 30 20 20
Waco 76 93 76 94 78 / 40 20 30 20 10
Paris 73 89 70 87 73 / 5 10 20 20 10
Denton 73 92 74 93 77 / 40 20 30 20 20
McKinney 73 91 73 89 75 / 30 20 30 20 20
Dallas 76 92 76 91 79 / 30 20 30 20 20
Terrell 74 91 74 91 76 / 30 20 30 20 20
Corsicana 76 92 75 93 78 / 30 30 30 20 10
Temple 76 95 75 97 77 / 30 20 30 10 10
Mineral Wells 74 93 73 94 75 / 50 20 30 10 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT this evening for TXZ091>094-105-123.
Excessive Heat Warning until 8 PM CDT this evening for
TXZ100>104-115>122-129>135-141>148-156>162-174-175.
&&
$$
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
1013 PM CDT Wed Jun 21 2023
...Short Term Update...
.UPDATE...
Issued at 1013 PM CDT Wed Jun 21 2023
- A few forecast update notes focused almost entirely on the
remainder of the "Tonight" period (through 12Z/7AM):
1) At least limited fog overnight?
Although the "usually reliable"fog forecasting tools (such as
SREF and HRRR visibility progs) don`t indicate much concern for
fog issues overnight into Thurs AM (especially of the
dense/impactful variety), likely due in part to at least modest
cloud coverage, felt that given that MOST of our CWA saw at least
a little rain today (and actually a good chunk of the area at
least 0.25")...that models might be underdoing at least
light/patchy fog potential somewhat given the light winds.
As a result, added an official mention of generic "patchy fog" to
especially much of the western 2/3rds of our CWA for at least a
brief time late tonight into Thurs AM.
2) Shower/thunderstorm potential:
Although this recent weather pattern is proving tricky to pin down
the details of rain/thunderstorm potential, earlier this evening
updated our forecast to confine any mentionable (15+ percent)
chance for showers/thunderstorms through 12Z/7AM to only about the
western 1/4 of our CWA. For sure, the VAST MAJORITY of convection
overnight should remain at least slightly west of our CWA
altogether, and despite SPC officially lingering an overnight
Marginal Risk of severe in our far west on their latest/final Day
1 Outlook, here locally we feel that any severe threat overnight
within our west would be quite minimal given overall-meager
instability/weak shear (and our Hazardous Weather Outlook/HWOGID
was updated as such).
Farther east into the majority of our CWA, there is probably a
non-zero chance for a rogue shower/sprinkle overnight, but felt
this chance was so low and/or coverage so limited that it was not
worth a formal forecast mention until beyond 12Z/7AM.
&&
.DISCUSSION...(This evening through Wednesday)
Issued at 418 PM CDT Wed Jun 21 2023
Key Messages:
* Thunderstorm redevelopment is possible late this afternoon into
the overnight hours.
* Periodic chances for showers and thunderstorms are expected
Thursday through Saturday as an upper trough moves in Thurs/Fri
and a cold front arrives on Saturday.
* Sunday and Monday will be dry, with additional chances for
showers/storms possible through the end of the forecast period.
The main change to the forecast has been the lowering of high
temperatures this afternoon, as persistent cloud cover and rain has
put a damper on warming this afternoon. High temperatures will be
mainly in the 70s with a few 80s for locations in the west, where
the rain clears out a little earlier in the day. The remnant line
of showers continues to decay as it moves east into Polk, York,
Fillmore and Thayer counties. There is potential for some
redevelopment of thunderstorms in our western counties late this
afternoon through the evening. An isolated strong to severe
thunderstorm may be possible with small hail, gusty winds and
locally heavy rainfall being the main concerns. The better chances
for strong and severe storms today/tonight will be for locations
to our west and southwest.
Thunderstorm chances increase west to east overnight and heading
into the day Thursday and Friday as a shortwave trough moves into
the region. The upper ridge will remain over the eastern two thirds
of the nation, with an upper trough beginning to come ashore over
Southern California. There is a chance for a few strong to
marginally severe storms, particularly for our western forecast
area on Thursday, and most of the area on Friday. The main hazards
expected with any storms that develop will be small hail, gusty
winds and heavy rainfall. Heavy rainfall may result in some
localized flooding, particularly for low-lying areas and locations
that have already had decent rainfall.
During the day Friday, models are showing the upper trough lifting
to the northeast into Wyoming and Utah. A closed low is expected to
develop along with an attendant cold front which is expected to slip
across the High Plains/Central High Plains on Saturday. Temperatures
will warm back into the mid-80s to low 90s Saturday afternoon, ahead
of the frontal passage. Showers and thunderstorms are expected to
develop along and ahead of the front. A few isolated strong to
marginally severe thunderstorms may be possible for areas mainly in
the northeastern part of the region. Precipitation ends west to
east through the day with dry conditions expected Saturday evening.
Sunday into Monday, expect a shift in the pattern as zonal flow sets
up over the region and the cold front moves east. Expect high
temperatures to be primarily in the 80s and lows to range from the
mid-50s to low 60s. After several chances for thunderstorms, Sunday
and Monday are expected to be dry.
Tuesday through the end of the forecast period, an upper ridge sets
up over the High Plains/Central High Plains. A few weak, embedded
shortwave troughs will move through the region, giving us chance for
some precipitation. Confidence in location, timing and coverage of
precipitation is low at this time.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 709 PM CDT Wed Jun 21 2023
- General overview (including winds):
High confidence in VFR ceiling/visibility and precip/thunderstorm-
free weather through at least the vast majority of the period.
The main POSSIBLE issues to watch for include: 1) a non-zero
chance for at least a brief period of sub- VFR visibility (and
perhaps ceiling too) a few hours either side of sunrise Thursday
IF any fog is able to form...2) A small chance for an isolated
shower and/or likely weak thunderstorm at some point mainly
between late tonight and the end of the period late Thurs
afternoon (more details below).
As for winds, outside of any yet-unforeseen thunderstorm outflow
influences (which of course could result in abrupt speed
increases/erratic direction), no significant issues are
anticipated. Sustained speeds will average near-to-below 10KT
throughout and direction will generally average variable most of
tonight and southeasterly most of the day Thursday.
- Ceiling/visibility/precipitation details:
As touched on above, there are mainly two items that COULD perhaps
cause deviations from official TAF expectations:
1) Given recent rain within the past several hours and
enhancement to low level moisture, there is some concern that at
least light fog development (with at least MVFR visibility) could
materialize especially a few hours either side of sunrise
Thursday. There is just not enough support in model guidance at
this time to include prevailing sub-VFR, but did at least "hint"
at the possibility with "6SM BR" 09-14Z.
2) Although especially these first 6 hours this evening are most
likely to remain precip-free, there appears to be at least a very
low-end (10-20 percent) chance of an isolated spotty shower/weak
thunderstorm really anytime after 09Z and into the daytime
Thursday. Given that these chances are so low and uncertain, have
opted against a formal precip mention in TAFs through most of the
period, except for later Thursday afternoon (21Z onward) at KEAR
where it appears a generic "vicinity shower" (VCSH) was most
justified.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...Pfannkuch
DISCUSSION...Wekesser
AVIATION...Pfannkuch
Area Forecast Discussion
National Weather Service Goodland KS
841 PM MDT Wed Jun 21 2023
.MESOSCALE DISCUSSION...
Issued at 822 PM MDT Wed Jun 21 2023
Key Message: Strong to possibly severe thunderstorms moving east
currently. Another round of storm activity anticipated later
tonight through Thursday morning.
Latest RAP soundings show a more stable environment in East
Central CO. However in KS the elevated CAPE has less CINH. If
storms are able to move east of CO, they may strengthen. Most
model data has the storm activity remaining over East Central CO
until close to midnight. Confidence is moderate there will be any
severe thunderstorms prior to midnight due to the lack of intense
convection currently. An upper level short wave ridge axis is just
east of the storm activity. This could be what is preventing the
storms from getting much further east.
Toward midnight another upper level short wave trough will move in
from the west. This short wave trough is currently accompanying
the storm activity along the Front Range. By the time the storm
activity reaches the forecast area it should have conglomerated
into a large area of storm activity. This looks to be the best
chance for storms for the forecast area tonight. The storm
activity should move into the forecast after midnight. Confidence
for severe weather with this round is lower due to the effective
shear being much less, around 20 kts. However the elevated CAPE
will be around 1500 j/kg as the storms move through. CAPE profiles
are tall and narrow, indicative of a flash flood threat.
This storm activity may slowly move across the forecast area
through the rest of the night and Thursday morning. With no change
anticipated to the upper level flow through Thursday evening, the
cloud cover behind the storm activity may linger over the forecast
area. This would prevent the environment from destabilizing during
the afternoon, preventing storms from forming until the next upper
level short wave trough moves through during the early evening.
On a sidenote, model data has been slowing down the entrance of
the upper level short wave trough and storm activity later
tonight. The current forecast may end up being a few hours too
early given the trend.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 1240 PM MDT Wed Jun 21 2023
As of 1 pm CDT, 12 pm MDT, skies across the Tri-State Region were
partly to mostly cloudy as a result of morning stratus/cumulus as well
as convective blow off from the overnight elevated storms across
north central Kansas. Clouds have held temperatures in the 70s so
far today although a few 80s are starting to show up where more
sunlight has been received. Low level moisture is quite impressive
with dewpoints in mid 60s with a few readings to around 70, well
above normal for this time of year. Winds were generally from the
east at 10-15 mph. At the surface, a clear outflow boundary was
visible extending from northern Yuma County to around Goodland,
Kansas and finally to near Russell Springs, Kansas. It`s moving to
the west, and should continue to do so over the next few hours.
Aloft, a shortwave trough is moving northeast, towards the Plains,
across northern New Mexico. Recent KGLD WSR-88D radar imagery and
GOES satellite imagery indicate recent convective initiation
along the boundary in Yuma County Colorado.
For the rest of the afternoon and into the evening hours, the main
focus will be this convective outflow and storms firing on that outflow
across eastern Colorado. Latest mesoanalysis indicates quite an
unstable environment has developed with SBCape of 2000-5000 j/kg, low
level lapse rates of 7+ C/km, and DCape of 1000+ j/kg available for
storm development. Wind shear is presently a limiting factor with 0-6
km bulk shear of less than 25 kts and 0-3 km SRH nearly non-existent at
this moment in time. CIN is near zero which is why we`re seeing storms
develop along this outflow boundary. Overall, expect storms to continue
attempting to fire on the outflow, and eventually some of them will be
able to sustain themselves. Low level shear should increase later,
closer towards 6 pm, and with LCLs quite low today, wouldn`t surprise
me if these initial storms were able to produce a tornado or two. Heavy
rainfall may also be a problem with slower storm movements.
For later tonight, expecting a larger complex to form out of the
evening convection forecast to fire along and just east of the Front
Range, east of Cheyenne, WY and Denver, CO. Overall, this looks like a
fairly confident forecast with the storms moving over as there will be
plenty of instability to work with, and higher DCape values should
promote a cold pools/outflow which will help organize the thunderstorm
complex. The main threats with this complex will be damaging winds and
also torrential rainfall, especially if there`s backbuilding on the
southwest side of the system as some models indicate. As a result of
all of this, the flood watch looks good to go and we should see some
widespread heavy rain. Latest guidance did back off some on how far
east the complex will make it, so that`s something to be mindful of.
For tomorrow, the overnight complex should have an impact on the
environment, though currently not sure how much of an impact. There
should be remaining cloud cover, and perhaps some ongoing shower and
thunderstorm activity during the morning. During the afternoon,
instability will once again build and we should see initiation along
any remnant outflow boundaries. As a result of the previous night`s
convection, the instability isn`t nearly as high as what we`re
currently observing. Wind shear does improve tomorrow though, with 0-6
km bulk shear of around 30-35 knots anticipated, so that may be a
compensating factor. The biggest question will be the CIN as a result
of the anticipated MCS and resulting daytime cloud cover. Overall, do
expect thunderstorm development during the afternoon, and some of these
could be strong to severe. However, did go ahead and lower pops as it
seems convection will be more isolated to scattered, not widespread as
previously anticipated. During the evening and overnight hours, it does
look like another complex of storms moves through the area from
northwest to southeast. There may be some potential for damaging winds
again, though the primary threat seems more likely to be heavy
rainfall.
.LONG TERM...(Friday through Wednesday)
Issued at 155 PM MDT Wed Jun 21 2023
Another round of severe weather is expected to start off the
extended period on Friday. The latest guidance is showing a
low/trough along the Front Range begin to slowly shift eastward late
in the day towards the KS/NE border. There is a weak 500/700mb
shortwave that works northeast along the periphery of the upper
ridge in the Plains. This will interact with the surface feature by
late afternoon into the evening hours to trigger some convection.
With a moist airmass in place with dewpoints in the 60s, PW values
are ranging from 0.90" west to the 1.50" mark east where the best
low level moisture resides. There will be a strong S/SE surface
gradient with gusts to 30 mph. Aloft, SW flow 20-30kts will provide
some decent shear with storms. Sfc/MUCape values around the 2000-
2500j/kg level with provide fuel to trigger strong to severe storms.
SPC continues to have Slight/Marginal risk areas for the
afternoon/evening hours. Best chances for severe potential look to
occur along/north of the Interstate, which tracks areas closer to
the surface low/trough that moves off the Front Range. WPC does have
a Marginal risk for excessive rainfall for mainly east of the
Colorado border. Torrential rainfall is probable with yet another
flood watch likely, but areas will be determined on what counties
get affected wed/thu.
This system clears the area by the upcoming weekend allowing for a
warm and dry period. Meandering upper ridge will provide a W/SW flow
aloft during this time. The ridge does sink a bit going into the
first half of next week as a couple shortwaves will move across the
northern periphery of the system. Passage will occur for the evening
and overnight hours, allowing for a dry yet humid daytime period(s)
each day through Wednesday. Best chances for storms will occur north
of the Interstate. While strong to severe storms could occur, with
high PW values/dewpts, heavy rainfall will probably occur in spots
and need to be monitored as the week progresses.
For temps, daytime highs for Friday into the first half of the
upcoming weekend will have low to mid 80s give way to mainly upper
80s to the lower 90s on Saturday, with warmest areas east. Going
into sunday, northerly flow will bring a cooler wider range with
upper 70s west into the upper 80s east. For the first half of next
week and that models carry most of the precip at night, mainly 80s
expected with some locales east around 90s, especially Wednesday.
Overnight lows will have mainly 50s with some 60s east for Friday
night into this weekend. For Monday night onward, 60s will begin to
build in from the east.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 526 PM MDT Wed Jun 21 2023
VFR to MVFR conditions forecast for the TAFs. Main impact will be
the storm activity impacting both TAF sites. The storm activity in
CO will move east out of CO during the evening. The activity may
reach KGLD as soon as 6z and KMCK as early as 9z. KMCK should be
north of the majority of the storm activity. Difficult to
determine how long the storm activity will last for KMCK.
Another round of storm activity may move through the TAF sites
during the latter half of the morning.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Flood Watch through Thursday morning for KSZ013-014-027-028-041-
042.
CO...Flood Watch through Thursday morning for COZ090>092.
NE...NONE.
&&
$$
MESOSCALE...JTL
SHORT TERM...RRH
LONG TERM...JN
AVIATION...JTL
Area Forecast Discussion
National Weather Service Grand Rapids MI
900 PM EDT Wed Jun 21 2023
LATEST UPDATE...
Update
.UPDATE...
Issued at 900 PM EDT Wed Jun 21 2023
Active fires in Quebec are sending a thick plume of smoke in from
the northeast this evening; about to enter ne Lwr MI from Lake
Huron. Latest HRRR smoke forecast suggests some rather thick smoke
will impact central and northern Lwr MI on Thursday, north of
about I-96. Even the near sfc smoke progs suggest over 20
micrograms/m3 so the smell of smoke may be noticeable. Other
upshot is that our sunny fcst for Thursday is likely in jeopardy
based on latest visible satellite imagery. Hazy or ptly sunny is
probably a better descriptor, particularly north of I-96.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 300 PM EDT Wed Jun 21 2023
Dry conditions persist across the region, though a very slight
chance for a shower does exist until this evening. Diurnal cumulus
field with bases of 5000-6000 ft have developed. Model soundings
from the 12z HRRR show surface dew points that are too low.
Interestingly, the Nam3km has a better handle on surface
dewpoints. Either way, fairly dry sub-cloud layers are shown. 12z
HREF 24 hr LPMM does show some light precipitation falling south
of I-96 today, but coverage of any potential showers would be very
limited. Will maintain 20% chance through the evening.
Thursday looks much the same. Dry conditions will dominate, winds
will continue from the east at 10 to 20 mph, and partly to mostly
sunny skies are expected with highs in the mid to upper 80s.
.LONG TERM...(Friday through Wednesday)
Issued at 300 PM EDT Wed Jun 21 2023
Forecast changes are limited in the long term as models have
remained fairly consistent. There are small chances for showers or
an isolated storm on Friday and Saturday afternoons. We have 20-40
percent chances for precipitation in both days. Beyond that time
frame, we continue to look at the Sunday through Tuesday period as
the best chances for rain in our area during the 7 day forecast. We
have 30-50 percent chances for showers and storms in the forecast
during the Sunday through Tuesday time frame. The best chances are
from Sunday into Monday with the upper wave pivots through the area.
As for precipitation amounts from Sunday into Monday, the
operational ECMWF has totals near 1 inch in spots with some totals
exceeding 1 inch. Surface dew points rise well into the 60s with
PWAT values near 1.5 inches, so the forecast totals seem plausible,
but it is more likely that totals in most areas will be less than 1
inch.
As for temperatures, the warmest day looks to be Saturday before the
clouds and precipitation spread in on Sunday. Saturday highs will
likely be up around 90. Highs early next week with the clouds/precip
will likely top out in the 70s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 754 PM EDT Wed Jun 21 2023
More of the same expected, with VFR conditions dominating tonight
and Thursday. An isolated shower from a scattered cumulus cloud
deck around 7000-9000 ft cannot be completely ruled out through
10 PM this evening and also on Thursday afternoon, but even the
VCSH remark was excluded from the TAFs given the very sparse
coverage. East sfc winds of 5 to 10 kts tonight, increasing and
turning gustier again on Thursday afternoon once deeper mixing
commences (10 to 20 kts generally during pk heating).
&&
.MARINE...
Issued at 300 PM EDT Wed Jun 21 2023
With easterly flow, wave action will continue to be limited on our
side of Lake Michigan. Generally, waves around 1 foot are less are
expected a majority of the time from now through Saturday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
UPDATE...Meade
SHORT TERM...Hoving
LONG TERM...Duke
AVIATION...Meade
MARINE...Hoving
Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1055 PM CDT Wed Jun 21 2023
.SYNOPSIS...
Issued at 1054 PM CDT Wed Jun 21 2023
Wednesday will be similar to yesterday, with highs in the upper
80s or low 90s, breezy easterly winds, and low relative humidity.
Little to no precipitation is expected through the end of the work
week. Temperatures remain warm through the weekend.
&&
.UPDATE...
Issued at 751 PM CDT Wed Jun 21 2023
Going forecast is largely on track this evening with quiet weather
expected overnight as temps drop into the lower to mid 60s. A
couple stray light showers formed this evening over Moultrie and
Shelby counties, possibly on a north-south oriented differential
heating boundary between gaps in the cirrus. 00Z KILX sounding
indicated 661 K/kg SBCAPE was present to support these showers.
This instability should diminish over the next couple hours as the
sun sets and expect the remainder of the night to be dry across
central Illinois.
Deubelbeiss
&&
.SHORT TERM... (Through Friday)
Issued at 244 PM CDT Wed Jun 21 2023
Rex block pattern remains in place over the upper levels today,
with high pressure in eastern Ontario and our persistent upper low
across the Tennessee Valley. A small swirl is seen in water vapor
imagery in western Kentucky, with showers just to its east. If
any of this reaches our forecast area, it would likely be closer
to sunset and mostly around Lawrenceville and Olney. Will keep the
20% PoP`s going in that area into early evening.
Otherwise, the low will remain fairly stubborn to move late this
week, but should start to get a northward nudge as the high slides
into New England. By midday Friday, synoptic models are in decent
agreement with it being centered over Ohio. We still don`t get
decent moisture flow during this period, and while some isolated
afternoon popcorn showers/storms can`t be ruled out over the next
couple days, the potential is too low to warrant a mention right
now.
The warmest weather will continue across the areas west of I-55,
with highs both Thursday and Friday around 90 or so. However,
latest HRRR is showing a decent slug of smoke aloft being drawn
into the area by sunrise Friday, so this will have to be watched
for potential temperature adjustments.
Geelhart
&&
.LONG TERM... (Saturday through Next Wednesday)
Issued at 244 PM CDT Wed Jun 21 2023
Upper low currently northwest of San Francisco will be swinging
northeastward late this week, and will be centered over Minnesota
by early Sunday morning. This storm system features the best
chances of getting any rainfall over the next several days, though
amounts do not look to be especially significant. Development of
an MCS across the upper Mississippi Valley is expected on
Saturday, but will be in a weakening phase if it manages to get
this far to the southeast. Latest ensembles continue to favor
lower rainfall amounts, with only about a 40% probability of more
than a quarter inch near and west of I-55 Saturday night and
Sunday. With this low only making it to lower Michigan by Monday,
wraparound showers will linger into the start of the work week.
Temperatures remain very warm to start the weekend, with highs in
the 90s, hottest over the sandy soils of the Illinois River
valley. However, a bit of a cooldown will follow beginning on
Monday.
Looking further out, the heat dome looks to build northward once
again across the central and southern Plains next week, edging
toward the mid-Mississippi Valley by mid week. However, there is some
question as to how much this will impact our area, with latest
CPC 6-10 day temperature outlooks currently favoring below normal
temperatures over the Midwest. Next chances of precipitation would
likely be with any ridge-rider MCS`s late in the week.
Geelhart
&&
.AVIATION... (For the 06z TAFs through 06z Thursday Night)
Issued at 1054 PM CDT Wed Jun 21 2023
Ridge of high pressure will over the Upper Midwest will result in
light NE winds and VFR conditions across central Illinois
overnight into the day Thursday. By Thursday evening, the ridge
axis will begin to settle near central Illinois allowing winds to
become light and variable.
Deubelbeiss
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Nashville TN
735 PM CDT Wed Jun 21 2023
...New UPDATE...
.UPDATE...
Issued at 729 PM CDT Wed Jun 21 2023
Widespread showers continue to rotate around an upper low centered
over Middle Tennessee. Rainfall rates are averaging less than 0.1"
in most areas, although there are still some pockets of heavier
showers ongoing. Predictably, the evening sounding from OHX shows
a nearly saturated profile with moderate instability. So we might
still see a thunderstorm or two embedded in the showers. The HRRR
shows rapid deterioration in radar coverage during the next 1-2
hours, with some regeneration after 06Z. Current forecast appears
to be in good shape for now, so no changes are planned this
evening.
&&
.SHORT TERM...
(This afternoon through Thursday Night)
Issued at 259 PM CDT Wed Jun 21 2023
At least through Thursday night, the wash, rinse, repeat theme of
the previous days will continue. Scattered to numerous showers
with isolated to scattered thunderstorms expected tonight. With
sustained northeast winds generally 10 to 15 mph, some colder
air to our north will more than likely work into mid state region
with lows tonight ranging low to mid 60s, upper 50s to around 60
for locations just west of and across Cumberland Plateau Region.
The development of a true north wind on Thursday will result in
the coldest temperatures of forecast period with highs spanning
the 70s, upper 60s Cumberland Plateau Region. Shower chances
will prevail through the day with increasing chances of
thunderstorms as day progresses as upper level low continues it`s
meandering across mid state region. That upper level low finally
begins what will be a slow northeasterly track out of our forecast
area initially on Thursday night. Good thing is that convection
will be confined to Cumberland Plateau Region with lows even a
degree or two colder in some locations, but again generally
ranging in low to mid 60s, upper 50s to around 60 Cumberland
Plateau Region. Through this short term period, some brief heavy
downpours with stronger showers and thunderstorms will occur at
times potentially leading to minor localized flooding and ponding
of water on area roadways, and it is also not out of the question
that maybe even some small hail with strongest thunderstorms
could be experienced in some locations. However, there continues
to be no indication of an organized potential for strong to severe
thunderstorms through Thursday Night as of this time.
&&
.LONG TERM...
(Friday through next Wednesday)
Issued at 259 PM CDT Wed Jun 21 2023
Look for that upper level low to continue drifting northeastward
as day on Friday progresses. Most morning convective activity will
continue to be confined to Cumberland Plateau Region with showers
and isolated to scattered thunderstorms prevailing across entire
mid state region by Friday afternoon. Highs on Friday will warm
slightly into low to mid 80s, mid 70s to around 80 for locations
just west of and across Cumberland Plateau Region. Upper level
ridging influences will finally build back across our area as
weekend progresses with dry conditions on expected except for
Cumberland Plateau Region Friday night and Saturday where some
isolated to scattered showers and thunderstorms may linger with
a better overall chance of convection across our area on Sunday.
Highs by Sunday afternoon will actually be a degree or two above
normal values, ranging upper 80s to lower 90s, low to mid 80s
for locations just west of and across Cumberland Plateau Region.
A surface front will approach our area as Monday progresses with
upper level flow becoming more northwesterly which could support
some organized convection developing to our north being brought
down in upper level flow. Upper level ridging influences will
build in from the west as first part of work week progresses
with some lingering convection expected through Tuesday with
dry conditions expected Tuesday night into Wednesday with
temperatures generally expected to be around seasonal normal
values.
&&
.AVIATION...
(00Z TAFS)
Issued at 614 PM CDT Wed Jun 21 2023
Periods of light rain will continue for the next few hours before
diminishing to scattered showers overnight. A few thunderstorms
will be possible through 02z towards the TN River. SCT to BKN
clouds 009-030 can be expected with the light rain. Cigs come up
some after 03z and should return to VFR. Low clouds build in
overnight 007-025 feet and MVFR and IFR conditions expected. Winds
under 10 knots.
&&
.PRELIMINARY POINT TEMPS/POPS...
Nashville 63 75 63 82 / 60 30 10 30
Clarksville 63 77 62 82 / 40 20 10 20
Crossville 58 68 58 74 / 60 80 30 60
Columbia 63 76 61 82 / 60 30 10 20
Cookeville 59 70 60 76 / 60 60 20 50
Jamestown 58 68 59 73 / 60 60 30 60
Lawrenceburg 63 75 61 81 / 70 30 10 20
Murfreesboro 64 74 62 82 / 70 40 10 30
Waverly 63 77 61 83 / 40 20 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE.......Rose
SHORT TERM...JB Wright
LONG TERM....JB Wright
AVIATION.....Mueller
Area Forecast Discussion
National Weather Service Pueblo CO
247 PM MDT Wed Jun 21 2023
.SHORT TERM...(This evening through Thursday)
Issued at 244 PM MDT Wed Jun 21 2023
Key messages:
1) dangerous thunderstorms capable of producing all severe weather
types along with high impact flash flooding will be possible in and
around the lower elevations of the Pikes Peak region later this
evening into the early morning hours.
2 More isolated strong to severe thunderstorms will be possible over
the plains this afternoon and evening, and once again tomorrow late
afternoon.
Currently...
A volatile atmosphere was noted over the plains this afternoon. CAPE
values were in the 3000 to 5000 range and effective shear was in the
30 to 40 knot range. The atmosphere, however, was capped.
Skies were mostly clear all areas, although low cumulus were note
dover the far eastern plains and up in the Pikes Peak region.
Temperatures were in the 80s plains nd 70s valleys. Much drier air
was noted over the mtns and valleys., and along the southern I-25
corridor region.
Rest of today (til 6 pm)...
CAMS show it should remain dry all areas, with the exception over
eastern El Paso county were an isolated strong storm will be
possible later this afternoon. I am also concerned that we may see
some isolated convection develop over the far southeastern plains
late in the afternoon. Otherwise, moisture will continue to push
back to the west, and expect the atmosphere over the region to
continue to destabilize.
Tonight...
There is not other way to put it, dangerous severe thunderstorms are
very likely over the Pikes Peak region, specifically western El Paso
county including all the metro areas of Colorado Springs. All of the
high resolution guidance continues to paint explosive thunderstorm
development occurring later this evening during the 9 pm to 10 pm
time period. CAPE values are progged to be 4000 to 5000 range and
effective shear is going to be in the 40 to 50 knot range per the
spc mesoanalysis page. Any sustained updraft that forms in this
environment will become severe, capable of producing very large
destructive hail, damaging winds and tornadoes. Additionally, latest
HRRR guidance is showing accumulating rainfall to 7 to 8 inches. I
do believe these values are overdone, but nonetheless, there is
likely going to be rainfall values that will easily cause flash
flooding.
Based on what we are seeing in satellite date, the main moisture
push was pushing west and the leading edge was moving across the CO
and KS border (this moisture surge was associated with all of the
convection in central KS earlier this morning). It is this boundary
that will continue to push westward and will initiate the main
explosive convection over the Colorado Springs region around 9-10 pm
tonight.
Most of the guidance only shows the most dangerous storms affecting
the greater COS region this evening, keeping most other areas dry.
However, the atmosphere over all of the plains will be very
volatile through the nighttime hours, and any storms that go up
will be capable of all severe hazards along with flash flooding.
In an earlier call with SPC, a watch will be issued later today for
parts, or all. of the plains, with giant hail being the primary
threat.
Tomorrow...
Expect mostly cloudy and cool weather over the plains, There may (or
may not) be convection ongoing across the far eastern plains early
tomorrow morning. Either way, I expect it to be rather stable over
the plains for a good part of tomorrow, and convection may not
develop into late in the day tomorrow. The primary severe threat
will be along the I-25 corridor.
.LONG TERM...(Thursday night through Wednesday)
Issued at 244 PM MDT Wed Jun 21 2023
Key Messages:
1) Lingering showers and storms Thursday night into very early
Friday.
2) Drying and warming pattern kicks in starting this weekend through
the beginning of next week.
Thursday Night and Friday...
Lingering showers and thunderstorms from Thursday`s convection will
potentially linger into the evening and early overnight hours thanks
to good surface moisture and a mid-level disturbance. As said
disturbance moves eastwards, precipitation will wane and move east,
clearing our area by Friday morning. A mid-level low will pass north
of Colorado during the day Friday, which may actually work to push
out moisture and dry things out. While a rogue isolated shower or
thunderstorm will be possible over the eastern plains Friday
afternoon, things should generally be on the quiet side.
Temperatures will also increase a fair bit from Thursday, with highs
in the low-80s over the high terrain and low-90s over the eastern
plains.
Saturday Onwards...
Upper-level ridging will build in starting on Saturday, giving us
above average temperatures and dry conditions across the area
through the rest of the extended period. Mostly clear skies will
also persist through the weekend. Some amorphous shortwave energy at
the mid and upper levels could give us some isolated afternoon
showers and thunderstorms, mainly over the higher terrain, but
otherwise things should be quiet. Long-range models and ensemble
solutions hint at a new system moving into Colorado around midweek.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 244 PM MDT Wed Jun 21 2023
...HIGH IMPACT WEATHER TONIGHT...
KCOS..
MAIN CONCERN --- Severe Thunderstorms will likely affect the KCOS
air space after 04 UTC tonight and lasting to about 07 UTC. Damaging
winds and destructive hail will be possible. Hailstones measuring 2
to 3 inches in diameter will be possible in and around KCOS.
In the meantime, and isolated strong to severe storm may develop
late this afternoon in the vicinity of KCOS.
After 07 UTC, MVFR/IFR conditions likely through tomorrow morning.
More thunderstorms will be possible late tomorrow afternoon.
KPUB...VFR through about 04-05 UTC, then a chance of strong to
severe thunderstorms through 08 UTC, MVFR/IFR through tomorrow
morning. More thunderstorms will be possible late tomorrow
afternoon.
KALS...
VFR through 24 hours. Gusty southwest winds this afternoon and
tomorrow afternoon
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Flood Watch from 6 PM MDT this evening through late tonight for
COZ084-085.
&&
$$
SHORT TERM...HODANISH
LONG TERM...GARBEROGLIO
AVIATION...HODANISH
Area Forecast Discussion
National Weather Service Springfield MO
554 PM CDT Wed Jun 21 2023
...00Z AVIATION UPDATE...
Key Messages:
1. A few storms possible over the eastern Ozarks this afternoon
and over southeast Kansas and far southwest Missouri tonight.
2. Warm and mostly dry Thursday and Friday.
3. Hot with increasing chances for storms this weekend.
4. Continued warm with periods of storms next week.
.SHORT TERM...(This evening through Thursday)
Issued at 145 PM CDT Wed Jun 21 2023
Current Conditions and Synoptic Pattern: Regional radar composite
shows the remains of a storm complex that developed over central
Kansas ahead of a north to south oriented boundary early this
morning drifting to the south-southeast across northeast and
central OK early this afternoon. A relatively dry and stable
airmass over the Ozarks and southeast Kansas has limited the
eastward extend of the complex so far. However, a mesoscale
vorticity center has developed over central KS and the latest HRRR
is picking up on it and generating some spotty precipitation over
our western counties tonight. So plan to add some low pops mainly
west of Highway 65.
On the eastern side of the forecast area, shallow cumulus have
developed in response to a weak disturbance on the northwest side
of the upper low parked over the Tennessee Valley. We may see a
few showers develop along the eastern edge of the forecast area
later this afternoon, but lack of deep moisture will limit
development over much of the area.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 145 PM CDT Wed Jun 21 2023
Through Friday: The Ozarks will remain under the influence of an
upper level ridge which will keep warm and mainly dry conditions
over the region. If any storms manage to form during the
afternoon, they will mainly be along the western and eastern edges
of the forecast area, closer to remnant outflow boundaries and
upper level disturbances. NBM output continues to show little
variation in high and low temp spreads over the next few days, so
will keep highs in the mid to upper 80s and lows in the upper 50s
to mid 60s going through Friday.
This Weekend: Confidence remains moderate to high that the upper
ridge over the central US will flatten as an upper trough moves
eastward from the Pacific Northwest into the central and northern
Plains. This will lower surface pressure along the lee slopes of
the Rockies and increase low level moisture influx into our area.
Will keep precipitation chances over the area beginning early
Saturday through late Sunday. The highest storm chances are
expected Saturday night into Sunday as a cold front trailing a
surface low over the Great Lakes moves across the area.
With increasing cloud cover and a Canadian High building into the
area, will likely lower high temperatures a tad on Sunday.
Monday through Wednesday: Model guidance is trending toward an upper
level northwest flow pattern over the Ozarks as an upper level ridge
builds across the southern high Plains, and an upper low deepens
over the Great Lakes on Monday and Tuesday. This will allow upper
level disturbances to move over the region. There are some
differences in whether or not the front that moves across the
region during the weekend stalls along our southern and western
edge, which would also lead to an uptick in storm activity.
By Wednesday and Thursday, there is a trend toward rebuilding the
upper ridge over the central Plains which would bring warmer and
drier conditions.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 553 PM CDT Wed Jun 21 2023
VFR conditions with light, easterly winds are expected to last
through the TAF period. There`s a low chance for a stray shower or storm
to affect KJLN, however kept this out of the TAFs, as chances are
20% or less.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Terry
LONG TERM...Terry
AVIATION...Melto