Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/06/24
Area Forecast Discussion
National Weather Service Cheyenne WY
429 PM MST Mon Feb 5 2024
.KEY MESSAGES...
- A messy storm system is expected to pass through our area
Wednesday into Thursday, bringing accumulating mountain
snowfall and scattered rain/snow showers for the valleys.
Gusty winds are possible Thursday as the system departs.
&&
.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 140 PM MST Mon Feb 5 2024
Current satellite imagery shows a very nice day across much of the
area with clear skies present for all except Carbon county.
Temperatures in the Nebraska panhandle are surging well into the
50s, while most of Wyoming remains in the 40s. Southwest flow aloft
is leading to some gusty winds across portions of Carbon and
Converse counties with wind gusts of 40 to 55 MPH possible through
the afternoon hours. The probability of exceeding high wind criteria
is around 30%, so while it can`t be ruled out, decided to cover this
risk with a Special Weather Statement through sunset. Height
gradients are elevated this afternoon as a weak vort max passes
across Montana, but expect winds to ease as this ejects off to the
northeast. However, a plume of deep moisture stretching across
California, Nevada, and Utah is pushing into southern Wyoming at
this time, and is expected to lead to increased cloud cover
beginning this evening.
Heading into tonight and Tuesday, the southwest flow aloft will turn
more southerly as a potent trough slowly moves inland into
California, amplifying the downstream ridge over the central Plains.
700-mb temperatures will warm up to +2 to +4C over the High Plains
by Tuesday which is at about the 90th percentile of climatology.
This should support a very mild day across most of the area, but
there are a few factors that will limit the warming potential
compared to other events with similar 700-mb temperatures. First,
the deeper moisture moving in aloft will result in more cloud cover
and less insolation. Second, surface winds over the high plains will
generally be out of the southeast, which is not a good wind
direction for downslope warming, especially in the southeast part of
the forecast area. Lastly, the remaining snow cover will keep things
a tad cooler where it remains in western/central Laramie county.
These factors will have the greatest impact in the Cheyenne area.
Further east, we don`t have the snow cover to worry about, and
further north and west, the wind direction will have more of a
downslope component which will aid warming. Overall, looking at
highs in the upper 40s to low 50s for southeast Wyoming from Rawlins
to Cheyenne, and mid to upper 50s with a few low 60s possible for
the rest of southeast Wyoming and western Nebraska without snow on
the ground.
Southerly flow aloft Tuesday night may have enough moisture to
return snow showers to the mountains and Carbon county. By
Wednesday, this slow moving system is expected to finally start to
push through our area. The latest guidance has the upper level low
traversing right over Wyoming, which keeps most of our area in the
warm sector Wednesday. While areas west of the Laramie range are
expected to cool down Wednesday, we should manage another mild day
further east, though not quite as warm as Tuesday. The track of the
low will keep the good lift and wrap around moisture well to the
north, but a saturated middle atmosphere with steep lapse rates may
be enough to kick off some scattered rain/snow shower activity
Wednesday over the High Plains. Precipitation totals are expected to
be modest, if any, and continued to trip PoPs below guidance.
However, moist flow impinging on our mountains will increase
Wednesday and Wednesday night. More details on this are covered in
the Long Term section below, but totals over Wednesday and Thursday
could approach Warning criteria in the Sierra Madre range. Current
amounts are borderline though, and the rates don`t really get going
until 48+ hours from now, so decided to hold off on any headline
issuance at this time. Still, some form of winter weather headline
is very likely at least for the Sierra Madre range, though
confidence is lower in the Snowy range and points east.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 140 PM MST Mon Feb 5 2024
Unsettled weather continues Wednesday night into Thursday
across the Rockies as a longwave trough remains over the area.
For Thursday...main 700mb low looks to be over central North
Dakota with pieces of energy moving through the longwave
trough. First shortwave moves into western Kansas Thursday
morning. Mountain snow expected to be ongoing as next shortwave
approaches from the west and southwest. Likely will see a break
in the weather during the day Thursday as CWA in between
shortwaves. Best areas to see snow continuing would be the
Sierra Madre and Snowy Ranges...though the Snowys will likely be
shadowed with the westerly flow aloft over the Sierra Madres.
Areas east of the Laramie Range likely to be dry Thursday late
morning through the afternoon.
Slow moving secondary shortwave moves into southwestern Wyoming
Thursday evening for an increase in PoPs across the Sierra Madre
and Snowy Ranges once again. Freezing levels 4000 to 4500 feet
should give most areas snow Thursday.
Will need to be on the lookout Thursday for strong winds over
the south Laramie Range. GFS forecasting 700mb winds up near
50kts Thursday morning...so there could be a brief window of
strong winds impacting Interstate 80 between Cheyenne and
Laramie.
Upper ridge builds back over southeast Wyoming Thursday evening
into Friday...ahead of shortwave number 3 that moves into
southwestern Colorado. This low may help pull a backdoor front
from the northeast back over Wyoming as suggested by the GFS.
The ECMWF suggests the front stays over northeast Wyoming
through Saturday with a more southerly trajectory of this 3rd
shortwave. For now...kept low end chance PoPs (25-30 percent)
across many areas with highest PoPs (60-70 percent) over our
western mountains.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 418 PM MST Mon Feb 5 2024
Generally MVFR to VFR conditions expected through the forecast
period for all terminals. Currently radar imagery has seen some
minor snowbands with gusty winds move across KRWL within the
last hour, which dropped visibility towards IFR categories with
some blowing snow across the terminal. That initial band has
since continued its track towards the northeast, bringing
conditions back towards MVFR. Latest HRRR model run has
continued to indicate maybe an additional band developing
between 00z and 02z this evening. Added a tempo group for KRWL
to capture any brief drops towards IFR in the event another band
develops. In addition, there are low end probabilities (under
15%) for fog to develop for KBFF tomorrow morning. Went ahead
and trended visibility and ceilings downwards for these
potentials, and will continue to evaluate in later TAF
issuances.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...MN
LONG TERM...GCC
AVIATION...MRD
Area Forecast Discussion
National Weather Service Dodge City KS
530 PM CST Mon Feb 5 2024
.KEY MESSAGES...
- Areas of Fog redeveloping after midnight east of highway 23
- Windy and warmer Tuesday.
- Intense south winds Wednesday, with gusts near 50 mph
expected.
- Isolated thunderstorms possible southeast counties Wednesday.
Strong outflow winds would be the primary threat.
&&
.SHORT TERM /THROUGH TUESDAY/...
Issued at 251 PM CST Mon Feb 5 2024
The near term forecast challenge will be any redevelopment of
lowered visibility in fog tonight. The HRRR was fairly on target
with the cloud cover this morning – maintaining a low stratus
layer over the bulk of the eastern 2/3rds or so of the forecast
area through mid afternoon. More sun has been seen in the
Garden City and Scott City area and west and southwest –
seemingly reflected in the temperatures getting into the low 50s
in those areas early this afternoon. The HRRR model would
suggest the stratus does not settle back in across the eastern
half of the area, but to a lesser confidence developing over
north central Kansas and perhaps as far as Hays and DDC
overnight. The HREF mean visibility and HRRR are both showing
potential for dense fog starting out around the DDC-Meade areas
and spreading northeast after midnight basically to most of the
highway 183 corridor (Hays and south) corridor before being
eroded on south winds early Tuesday. The coming day Tuesday will
be warmer than Today with more sun and southerly winds
factoring into afternoon warming into the 60s. Overall
temperatures are forecast around 10 to 15 degrees warmer than
Monday.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Issued at 251 PM CST Mon Feb 5 2024
The area does get under a transient 500 mb ridge moving slowly
west to east across the area through midweek/Wednesday – with
plenty of mid and high cloud cover ahead of a cold front
expected on Wednesday night or Thursday. NBM is already
producing some marginal QPF (a few hundredths of an inch) across
our southeastern half of the area on Wednesday/Wednesday Night
– in advance of a cold front and dry slot that moves through the
area south of a north plains synoptic cyclone.
A lot of ensemble member consistency exists with respect to at
least limited precipitation later in the week and upcoming
weekend – centered mostly around Sunday. The GFS ensemble mean
for a few runs now has produced around 0.15” to around a
quarter inch of QPF late Sunday at DDC. The areal coverage is
fairly well distributed as well with reasonably similar output
for Hays and Liberal. The bigger forecast question is probably
will it snow and how much. Similar time window GFS ensemble
means are producing 24 hour snow totals to a half inch to an
inch and a half, over than last 5 or so runs.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 530 PM CST Mon Feb 5 2024
Latest visible satellite imagery reveals clear skies across most
of southwest KS, with a small band of IFR stratus hanging on
over HYS. With sunlight quickly fading, short range guidance
suggests this small band of clouds will be sustained, leaving
HYS mired in IFR/MVFR stratus for much of this TAF cycle while
all other terminals enjoy VFR through the end of the period.
Another round of dense fog development is expected this evening
mainly across central KS, and the latest high-resolution models
suggest this too will reach HYS, likely sending HYS into LIFR or
perhaps lower. It is possible this fog reaches DDC as well, but
confidence was much lower and therefore any fog mention was left
out of the TAF. Otherwise, light and variable winds will
continue through Tuesday morning. Around 15-17Z, winds will
increase out of the south into the 10-20 kt range with gusts of
30-35 kts possible.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Springer
Area Forecast Discussion
National Weather Service Sioux Falls SD
854 PM CST Mon Feb 5 2024
.KEY MESSAGES...
- An abundance of sunshine this afternoon will give way to more
areas of fog this evening and overnight especially east of
the James River Valley. Visibilities less than a mile are
expected through at least the mid-morning hours on Tuesday.
- Well above normal temperatures will continue through Thursday
with the continued potential for record-breaking warm low
temperatures each night across the area.
- Measurable precipitation chances (40%-70%) return to the
region from Wednesday afternoon through Friday morning
especially north of I-90. While most precipitation should fall
as rain, confidence continues to increase in a transition to
light snow around the Hwy-14 corridor Thursday night into
Friday with light accumulations expected.
&&
.UPDATE...
Issued at 844 PM CST Mon Feb 5 2024
Have significantly reduced fog coverage this evening as models
continue to back off on fog potential tonight. This is likely
due to our southerly winds helping to keep temperatures from
falling as far and as quickly as expected. So far, fog has been
patchy outside of south central SD, where stratus lingered
through the day and fog/stratus have been advecting northward
out of NE. Will continue to watch trends, but for now, am
cautiously optimistic in the trends downward in coverage.
&&
.DISCUSSION...
Issued at 338 PM CST Mon Feb 5 2024
The Short Term (This Evening/Tonight):
An abundance of sunshine returns! Taking a look at satellite
imagery, most of this morning fog has dissipated across the area as
the surface inversion weakened giving way to clearer skies and an
abundance of sunshine. This along with southerly surface winds
should help us quickly reach our highs in the mid to upper 40s for
the day. However, as our dew point depression shrinks after sunset;
expect another round of fog to develop tonight most along and east
of the James River. Looking at high-resolution guidance, both the
HRRR and RAP have the areas of fog starting to develop along the
James River Valley closer to 03z and slowly shifting things further
eastwards towards the Hwy-81 corridor as the winds strengthen
overnight. After collaborating with neighboring office, we`ve
decided to hold off on a dense fog advisory for now. However, an
advisory will likely be necessary from the Hwy-81 corridor
eastwards though the mid-morning on Tuesday. Otherwise, the
above normal temperatures will continue overnight as lows
approach freezing. The warmest conditions will likely occur west
of the James River with lows in the mid to upper 30s expected.
Lastly, as temperatures cool overnight; we`ll have to watch to
see if another record warm low temperature can be set at our
climate site in Huron (KHON).
The Long Term (Tuesday-Sunday):
Looking into the rest of the week, the warming trend continues into
into the midweek as amplified ridging returns to the region by
Tuesday. Increasing 850:700 mb warm air advection (WAA) along with a
surface warm front should keep things on the milder side at least
through Thursday as temperatures hover between the 90th to 99.5th
percentile of climatology according to the ESAT Tables. With this in
mind, daily highs are expected to reach the upper 40s to low 50s
from Tuesday through Thursday. However, with more areas of fog
expected on both days; figured it would take slightly longer to
break the inversion in the mornings to start mixing. As a
result, I nudged down our high temperatures a few degrees
towards the 25th percentile of guidance using a blend of the
CONSall. Otherwise, the above normal temperatures will carry
over into the night resulting in lows mostly in the 30s to low
40s each night. If thing can stay on track, we would be able to
set new record warm lows across most of our climate sites from
Tuesday night through Thursday night.
Shifting gears to our precipitation chances, our attention likely
will pivot to the western CONUS starting on Wednesday as a broad
upper-level trough moves into the Rockies bringing increased
precipitation chances (40%-70%) to the northern plains from
Wednesday afternoon through Friday. While most of this precipitation
should fall as rain from Wednesday through Thursday, confidence
continues to increase in a brief transition to light snow Thursday
night into Friday morning as moisture wraps around the surface low
and cooler air funnels into the area. Looking at amounts, ensemble
guidance continues to show medium to high confidence (70%-90%) in
QPF exceeding 0.10" inches of precipitation and low to medium
confidence (40%-60%) in about an inch of fresh snow along the
Hwy-14 corridor. Otherwise, most of our precipitation chances
should come to an end by Friday night as the surface low tracks
northeastwards from eastern Colorado into central Minnesota.
Looking into the weekend, slightly cooler and quieter conditions
return to the region behind the surface low as quasi-zonal flow
returns aloft. The last thing to note is that ensemble guidance
continues to show shift towards cooler conditions starting this
weekend. With that being said, daily highs will likely drop back
into the low to upper 30s again with this trend continuing into the
second week of February. Nonetheless, that is still above our
seasonal threshold for this time of the year.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 530 PM CST Mon Feb 5 2024
VFR conditions for most of the area early this evening will
quickly deteriorate as stratus and fog expand. Expect MVFR/IFR
and some LIFR ceilings and visibility to prevail from mid to
late this evening into mid Tuesday morning. Improvement is
expected Tuesday morning into the afternoon, although patchy
MVFR/IFR conditions may linger through the day.
Southerly winds through the period around 10-15 knots, with
gusts to 20 knots.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.
&&
$$
UPDATE...SG
DISCUSSION...Gumbs
AVIATION...
Area Forecast Discussion
National Weather Service Fort Worth TX
610 PM CST Mon Feb 5 2024
...New Short Term, Aviation...
.SHORT TERM... /NEW/
/Tonight through Wednesday Morning/
An upper level ridge is currently located just to our west as
seen on Water Vapor satellite imagery and will continue to move
eastward overnight into tomorrow morning. As such North and
Central Texas will persist under subsident air, keeping our
sensible weather quite calm through midweek. With clear skies and
light winds, expect low temperatures to bottom out in the mid-
upper 30s (though some in the DFW urban heat island will see a low
around 40).
Under the aforementioned conditions (clear, calm, and dry), some
very patchy fog may be able to form across the northern reaches of
North Texas overnight into tomorrow morning. However, guidance is
not too keen on the occurrence of major visibility restrictions
as probabilities are quite low at this time and only for an hour
or two near or just after daybreak. The guidance currently picking
up on the occurrence of patchy fog the hardest is the NAM MOS,
which is generally more of a "worst case" guidance. Additionally,
the 12Z HREF has 40% of members picking up minor visibility
restrictions, however the HRRR has really backed off on more
recent runs which will affect the 00Z HREF output when it comes
in. All this to say: while patchy fog is a possibility overnight,
any occurrence is still quite uncertain and will need watching
this evening as newer guidance comes in.
The apex of the ridge will move overhead during the afternoon
tomorrow, with increased cloud cover moving along the flow of the
ridge from W to E. Afternoon temperatures will be able to peak in
the mid 60s region-wide. While winds will begin to shift back to
southerly flow, true return flow will not occur until later in the
night. With persisting cloud cover and southerly flow at the
surface and low levels overnight, temperatures will be warmer to
start out midweek. Expect Wednesday morning lows in the low to mid
40s.
Prater
&&
.LONG TERM... /Issued 224 PM CST Mon Feb 5 2024/
/Wednesday Through The Weekend/
Dry conditions and warming temperatures will prevail Wednesday as
North and Central Texas remain under the influence of high
pressure/ridging at the surface and aloft. By Wednesday morning, a
digging upper level trough from the Pacific Northwest will begin
to weaken slightly as a jet streak shifts east of the trough axis
and lifts the trough northeast towards the Dakotas. With another
trough digging along the west coast immediately in its wake, broad
upper-level troughing will become stretched across the western
two thirds of the CONUS through the remainder of the extended
period.
In the lower levels, the associated surface low pressure
developing in the Central Plains and a 30-40kt SSW LLJ will
enhance moisture advection into the region. By early Thursday,
upper-level support from the first ejecting mid-level shortwave
and persistent warm/moist advection may aid in the development of
isolated to scattered showers throughout the day. However,
precipitation is likely to remain limited to areas east of the
I-35 corridor, as a pronounced layer of dry air in the mid levels
keeps PWATs below 1 inch further west.
A weak Pacific front is expected to sag southward through the
Plains (potentially stalling somewhere nearby) and providing a low
level focus for additional convective development Thursday into
Friday. Some areas, particularly west and north of the Metroplex,
may remain precip-free through Friday however, as limited (pre-
existing) moisture and the rapid arrival of post-frontal dry air
supersede the favorable dynamics. Predictability in the evolution
of the trailing shortwave(s) that are expected to dig along the
western flank of the longwave trough late Friday and into the
weekend remains fairly low unfortunately.
While the GFS/ECMWF ensemble means and deterministic guidance are
gradually trending towards a more amplified trough traversing the
southern Rockies late Saturday or Sunday there remains a
considerable spread in key details (including track,
amplification, timing) which will have sensible weather impacts.
Though the NBM continues to adjust/oscillate between slight
chance to chance PoPs as a mean between the wetter and drier
solutions, overall rain chances are expected to become more
widespread this weekend with the entire region seeing a chance for
rain by Saturday afternoon through much of the day Sunday.
Additionally, despite the lingering uncertainty/spread amongst
guidance, there will likely be enough instability present for a
few stronger thunderstorms somewhere across the region as well.
Many of these details will be hammered out through the week as we
begin to see more agreement among guidance.
12
&&
.AVIATION... /NEW/
/00Z TAFs/
North to northwesterly winds will continue to decrease in speed
this evening, eventually becoming AOB 5 kts overnight. Though
sometimes variable, the general flow will veer easterly tomorrow
morning with light speeds persisting. Southeasterly flow will
return to the TAF sites just after noon tomorrow, and remain
through the rest of the period. VFR will prevail with increased
cirrus coverage moving in from west to east over the day tomorrow.
Prater
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 40 65 46 68 55 / 0 0 0 0 10
Waco 39 65 43 66 56 / 0 0 0 0 5
Paris 36 63 41 64 51 / 0 0 0 0 5
Denton 36 64 42 66 53 / 0 0 0 0 10
McKinney 36 63 43 66 53 / 0 0 0 0 10
Dallas 39 65 46 66 55 / 0 0 0 0 10
Terrell 37 63 42 66 53 / 0 0 0 0 5
Corsicana 40 65 45 69 56 / 0 0 0 0 5
Temple 38 66 42 68 54 / 0 0 0 0 5
Mineral Wells 38 66 43 69 53 / 0 0 0 0 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Goodland KS
253 PM MST Mon Feb 5 2024
.KEY MESSAGES...
- Strong SSW winds (~30-45 mph gusting to ~55 mph) will create
hazard travel conditions during the day on Wednesday.
- Cooling trend Thursday through Sunday with chances for rain
showers and snow showers.
&&
.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 245 PM MST Mon Feb 5 2024
Synoptic Overview: An amplifying upper level ridge over the
central CONUS will shift east toward the Mississippi River
Valley Tue-Wed.. as a large upper level low (presently centered
offshore the central California coast) progresses
inland/eastward across the Intermountain West.
Tonight: Visibility forecasts via recent runs of the HRRR
suggest that dense fog may develop over portions of the area
late this evening and overnight.. most likely along/east of
Highway 83.. where low stratus persists (as of 21 UTC).
Confidence in fog coverage and duration remain below average.
Tue-Tue night: A low-level southerly return flow regime will be
established in this period (noticeably-so Tue night).. as the
aforementioned ridge shifts east of the High Plains and upstream
height falls /strengthening SW flow atop the Rockies/ foster
the development of an increasingly pronounced lee trough/cyclone
in Colorado. A thick/opaque veil of cirrus.. associated with an
influx of upper level moisture via strengthening SW flow
aloft.. will foster overcast conditions across the majority of
the area in this period. A 10-20 mph south breeze (during the
day) will increase to 20-30 mph during the late evening and
overnight hours.. as the MSLP-H85 height gradient tightens on
the eastern periphery of the deepening lee cyclone in Colorado.
Wed-Wed night: Strong SSW winds are anticipated across the
majority of the area during the late morning and afternoon.. as
the MSLP-H85 height gradient further tightens on the eastern
periphery of the [still] deepening lee cyclone in northeast
Colorado. Guidance indicates that widespread upper level cloud
cover will shift eastward into central KS during the day.. and
that unimpeded insolation will aid in the development of a
rather deep (6-8 KFT AGL) mixed-layer by mid-afternoon. GFS
forecast soundings suggest that 35-50 knot southerly /SSW-SW/
low-level flow will be present within/throughout the deepening
mixed-layer, strongest along/east of Highway 25 in northwest
Kansas.. on the eastern periphery of the eastward advancing lee
cyclone.. where the MSLP-H85 height gradient will be tightest.
With the above in mind, expect sustained SSW-SW winds on the
order of 30-45 mph and gusts up to 60 mph.. windiest (overall)
along/east of Highway 25.. where peak heating /deep vertical
mixing/ will more favorably overlap with stronger low-level flow
on the eastern periphery of the aforementioned lee cyclone.
While reductions in visibility assoc/w blowing dust cannot be
ruled out over portions of western KS.. saturated ground
conditions associated with recent rainfall and snow-melt will
likely be a significant limiting/mitigating factor. Either way,
hazardous travel conditions will be the primary impact..
especially on west-east routes such as I-70, where cross-winds
will be strongest.
Interestingly.. unimpeded insolation may yield ~250-500 J/kg of
MLCAPE invof the KS/CO border at peak heating.. indicating a
potential for high-based, low-topped convection (lifted
condensation level ~8 KFT, equilibrium level ~23 KFT) in the
~21-00Z time frame. Simulated reflectivity forecasts via the 18Z
NAM NEST suggest that scattered convection may develop *behind*
the dry line in southeast CO.. a hint that convective
development (if any) may largely be a function of upper level
forcing (e.g. DPVA).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
Issued at 234 PM MST Mon Feb 5 2024
A generally wet pattern is expected through the long term with
potential for the Tri-State area to see both rain and snow.
On Thursday, a cold front is expected to move southeast across the
area bringing some weak chances, less than 30%, for light rain and
perhaps some light snow for those generally west of Highway 83.
Little to no snow accumulation is expected should any snow develop
Thursday night. Weak shortwaves and wrap around moisture from a low
pressure system moving towards the Upper Great Lakes will continue
rain/snow chances on Friday. Friday morning could see the tapering
off of the Thursday precipitation for those along and west of the
Colorado border followed by a possible short break during the
afternoon hours as a surface low develops over Eastern Colorado.
Friday evening, the surface low is currently anticipated to move
south towards the Panhandle region while moisture works it`s way
across the Rockies to the High Plains.
Friday night, precipitation chances are expected to slowly increase
from west to east. These chances, ranging from 20-45%, are expected
to linger over the area through Sunday. Light rain and snow are the
current forecasted precip types, with the snow becoming widespread
late Saturday afternoon through Sunday afternoon before chances
decrease. It`s still a little too far out for amounts to be
discussed; however, we are looking at a wet heavy snow with snow to
liquid ratios ranging from 7-12:1. There remains a decent amount of
uncertainty for how deep the trough becomes as well as how quickly
the system moves over the Rockies.
Temperatures look to be above normal on Thursday with highs in the
50s to around 60 degrees and overnight lows in the 20s to lower 30s.
Friday may be slightly cooler with highs in the upper 40s to lower
50s over east-central Colorado and up to the mid 50s for the
remainder of the area. Overnight lows are forecast to fall into the
20s overnight. Over the weekend, highs are expected to be in the 40s
both days with overnight lows in the upper teens to mid 20s.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 245 PM MST Mon Feb 5 2024
GLD: VFR conditions are anticipated to prevail through the TAF
period. While a period of sub-VFR fog and/or stratus cannot be
ruled out after sunset this evening, confidence is low enough to
preclude mention with the current TAF issuance. 7-12 knot S to
SSW winds will prevail through Tuesday morning.. increasing to
12-18 knots during the afternoon.
MCK: VFR conditions have returned as of 2150 UTC this
afternoon. Redevelopment of fog and/or stratus cannot be ruled
out this evening and overnight.. confidence is below average. A
TEMPO group for IFR conditions has been introduced in the 09-13Z
time frame Tuesday morning. Light/variable winds will shift to
the S-SSW this evening.. remaining S-SSW at 6-12 knots through
the duration of the current TAF period.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.
&&
$$
SHORT TERM...Vincent
LONG TERM...KMK
AVIATION...Vincent
Area Forecast Discussion
National Weather Service Pocatello ID
306 PM MST Mon Feb 5 2024
.SHORT TERM...Today through Tuesday Night.
Well. The snow was able to make it farther east than anticipated
into Idaho Falls and thrived at 34-36 deg F throughout the morning
before switching to rain at 35/36 deg F around 11AM. Warmer
temperatures through the afternoon will support all rain through the
Magic Valley and most of the Snake Plain while snow continues in the
higher elevations, especially in the Eastern Highlands. With this
lull in activity for the Wood River area/Central Mountains/Arco
Desert, have decided to end the Winter Storm Warning a couple of
hours early for these areas. It will continue up in the northeast
along with the Winter Weather Advisories for the Big Hole Mountains
and Bear River Range. In the lower elevations of the Eastern
Highlands, look for about 1-3 inches of snow this evening/tonight.
This atmospheric river event isn`t done yet and we`ll see more
moisture moving through the area tonight and tomorrow.
Unfortunately, the area north of Blackfoot/around Idaho Falls looks
to have the greatest uncertainty in potential snow accumulation
again. It will likely be a tight gradient and both the NBM and HREF
say Idaho Falls will stay all rain thanks to the continued warmth
moving in today. However, the NAM Nest and HRRR suggest up to about
1.5 inches in/very near Idaho Falls. At this point, I`m not going to
discount either scenario as this will likely come down to a
difference of just a couple of degrees again which models may not
resolve until tonight.
With this second push of moisture early Tuesday through early
Wednesday, have gone ahead an put out some more winter highlights.
These include a Winter Storm Warning for parts of the Central
Mountains (Ketchum, Sun Valley, Galena Summit) where snow totals
will be up in the 4 to 9 inch range with totals closer to 12 to 18
inches up on the ridges and Winter Weather Advisories for the rest
of the Central Mountains up into the Centennial Mountains/Island
Park area where snow totals will be up to 5 inches with higher
totals of 7 to 12 inches on the ridges. Snow totals through much of
the lower elevations of the Southern Hills and Eastern Highlands
will range from 1 to 3 inches. Temperatures Tuesday night into
Wednesday will drop close enough to freezing to all for a light
dusting of snow in the Magic Valley and Snake Plain, but look for
rain Tuesday afternoon as temperatures warm once again and we see a
brief lull in activity for some. AMM
.LONG TERM...Wednesday through next Monday...
As we arrive into Wed, the axis of the overall synoptic trough
responsible for all the moisture this week will slowly be inching
into the CWA, but progress will be slow as multiple embedded mid-
level lows/pieces of energy will continue shifting overhead
through at least Fri eve. Snowfall may be nearly continuous in
many mntn areas...and especially the Island Park region...while
coming in lighter waves across lower elevations such as the ern
Magic Valley, Snake Plain, and adjacent valleys. Anywhere from
another light coating in Shoshone and Burley, to an inch or two in
Hailey, Pocatello, and Idaho Falls, to 2-6 inches across most
mntns and 4-8 inches in the Island Park region, Big Holes, and
Bear River Range is expected Wed eve through Fri eve, with temps
slightly cooling each day supporting almost all snow from Wed eve
onward. Most QPF really drops off by late Fri eve, leaving us
largely on the back side of the departing synoptic trough with
weak ridging or at least W-NW flow nudging in for the weekend with
overall drier conditions. This trend is widely reflected across
the 500mb height ensemble clusters as well, although the ridge is
not strong or anchored nearby and thus we will need to watch for
moisture or even bonafide shortwave troughs riding in on the W-NW
flow or flattening the weak ridging signature (as is hinted at in
the 12z deterministic suite). 01
&&
.AVIATION...Quite a challenging aviation forecast today with a mix
of rain and snow showers along with variable cigs areawide.
Currently the moisture stream associated with the atmospheric
river is over the eastern periphery of Idaho. This may spell a
quieter period for our western ports of KBYI and KSUN through the
afternoon/evening today. Far to our south on satellite one can
clearly identify the deeper moisture stream that will continue to
push north through the afternoon/evening. This will drift the fire
hose of precipitation back westward overnight and into Tuesday.
We`ll see a similar regime in place for rain/snow cutoffs tonight
and into Tuesday as we had this morning. KBYI and KPIH should
likely remain rain, while KIDA will be somewhere near that
rain/snow line and the impacts associated with it. KSUN and KDIJ
should stay in the snow and thus could see lower visibilities
throughout. TAX
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 5 AM MST Tuesday for IDZ060-064.
Winter Storm Warning until 5 AM MST Tuesday for IDZ066-067.
Winter Weather Advisory from 5 AM Tuesday to 11 AM MST Wednesday
for IDZ066>069-075.
Winter Storm Warning from 5 AM Tuesday to 11 AM MST Wednesday
for IDZ073-074.
&&
$$
Area Forecast Discussion
National Weather Service Springfield MO
503 PM CST Mon Feb 5 2024
.KEY MESSAGES...
- Above average temperatures are likely this week (90% or
higher chances of highs in the 50s and 60s).
- Gusty south to southwest winds late Wednesday into Thursday (70-90%
chance of wind gusts up to 35 to 40 mph).
- Low rain chances (20-40%) return on Thursday.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 200 PM CST Mon Feb 5 2024
Through Tonight: An upper-level ridge continues to build into
the region. As surface high pressure settles over the central
CONUS, winds become rather light and variable through tonight.
Overnight lows fall into upper 20s to lower 30s. Some patchy
fog may develop in low-lying areas and lakes/streams, though
widespread fog is not expected.
Tuesday: The gradual warming trend continues into Tuesday with
mostly sunny skies and highs reaching into the middle to upper
50s. This is around 5 to 10 degrees above normal for early
February. This is a result of 850mb temperatures warming around
8 to 10 C through mid-week. Local climatology suggests highs may
nudge a few degrees higher than forecast.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 200 PM CST Mon Feb 5 2024
Wednesday-Thursday: The upper-level ridge remains intact over
the central CONUS on Wednesday afternoon, as highs push upper
50s to lower 60s despite increasing cloud cover ahead of an
approach trough across the western CONUS. Short term guidance
suggest favorable elevated grassland fire conditions by mid to
late Wednesday afternoon across the western portions of the
area. Minimum afternoon relative humidity values are around 35
to 40 %.
By Wednesday night, surface low pressure will develop and move
northeast across the Plains. A strong pressure gradient
strengthens over the area Wednesday night into Thursday,
supporting strong south- southwest wind gusts. LREF (global
ensemble) depicts a 60 to 80% probability of wind gusts
exceeding 40 mph west of Highway 65 on Thursday afternoon. In
general, 35 to 40 mph wind gusts will be common across this area
on Thursday afternoon and may need addressed with a Wind
Advisory headlines if confidence and wind speeds continue to
increase through mid-week. Meanwhile, strong southerly flow will
support highs climbing into the lower to middle 60s on
Thursday.
An associated cold front with the lifting low to the north of
us will feature low rain chances (20-40%) on Thursday afternoon
and evening. Guidance continues to suggest chances are highest
along and east of the Highway 65 corridor through Thursday
evening. Moisture return is fairly limited with this system,
and the better lift positions north and east of the region.
Rainfall amounts would be limited to a few tenths, with many
locations remaining dry.
Next Weekend: Despite the frontal passage, temperatures remain
mild into Friday with highs in the middle to upper 60s. Breezy
southwest winds (20-25 mph) persist into Friday afternoon.
Ensemble guidance and individual members differ into next
Saturday and Sunday on the timing and location of an upper level
trough and associated low. For now, we will continue to
advertise some precipitation chances returning to the region.
Additionally, the trend would support a bit cooler temperatures
with highs returning near normal in the upper 40s. There
remains considerable variance and will continue to monitor in
future forecast updates.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 501 PM CST Mon Feb 5 2024
For the 00z TAFS, will need to watch western MO and southeast KS
for some fog potential tonight. While most of the CAMS are not
depicting any, the HRRR and NAM are bringing in some dense fog
after 09z. For now, will go with 3sm and a tempo 1sm group
between 10z and 14z at JLN. BBG and SGF should remain in VFR
with a light wind.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
KS...None.
MO...None.
&&
$$
SHORT TERM...Perez
LONG TERM...Perez
AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Sacramento CA
109 PM PST Mon Feb 5 2024
.Synopsis...
Active weather persists through the remainder of the day. Periods of
moderate to occasionally heavy mountain snow showers linger
becoming lighter through midweek. Isolated Valley and foothills
thunderstorms are also expected through this evening. Another
weaker system arrives late Wednesday into Thursday, bringing a
quick burst of light showers to interior NorCal. Quieter weather
then prevails into next weekend.
&&
.Discussion...
Overall forecast precipitation totals are trending down as this
system wraps up for interior NorCal, but scattered rain showers and
areas of mountain snow showers persist. With a few intermittent
breaks in cloud cover occurring throughout the Valley, latest RAP
mesoanalysis is indicating some weak instability, on the order of a
few hundred J/kg, building. While areas of stronger low level shear
have drifted primarily over the Sierra, given the orientation of the
jet around the upper trough off the coast, 0-6 km shear is in the 30-
60 kt range in the Valley, strongest over the northern San Joaquin
Valley. This combination of weak instability and modest mid level
shear will likely be enough to sustain a few updrafts for isolated
thunderstorm development this afternoon. With any thunderstorms that
develop, gusty winds, small hail, brief heavy rain, and a few
isolated instances of funnel clouds will be possible. Latest short
term guidance indicates the most likely time frame for isolated
thunderstorms will be through 06z this evening for Valley and
adjacent foothills locations.
As for mountain snow, areas of showers continue for the Sierra and
coastal range. Snow levels in the Shasta County area are in the 3500-
4000 foot range, with snow levels 5000-6000 feet currently being
observed over the Sierra. Snow showers over the coastal range look
to persist into the evening and taper off overnight, with
activity over the Sierra lingering into Tuesday. As Valley and
foothills thunderstorms push up the Sierra late this evening into
the overnight hours, this convective component will lead to the
potential for periods of locally heavy snowfall as well. As a
result, probabilities of exceeding 8 inches of additional snowfall
over the Sierra through Tuesday morning are in the 40 to 50%
range at pass level, with 60 to 80% probabilities at higher peaks.
Breezy southerly winds persist today as well, with strongest winds
in the northern Sacramento Valley. These winds are expected to
continue to taper off through the remainder of the day, shifting to
a light northerly wind on Tuesday. The primary upper trough,
currently still lingering off the coast, looks to gradually move
inland over southern California moving toward midweek. The north-
northwesterly flow pattern falling into place over interior NorCal
in its wake will then allow for a quick moving shortwave to impact
the region late Wednesday into Thursday. Much lighter precipitation
is expected with this system than compared to previous systems.
Forecast precipitation totals indicate generally 0.10 to 0.25 inches
in the Valley and foothills, with 0.25 to 0.50 inches possible over
the Sierra. Snow levels do look to be low, generally 3000 to 4000
feet, but heaviest snowfall totals of 3 to 6 inches are expected
primarily above 5000 feet.
&&
.EXTENDED DISCUSSION (Friday THROUGH Monday)...
Ensembles and clusters indicate that upper level trough will
shift over the Great Basin Region Friday, as Eastern Pacific ridge
begins to build over NorCal. Upper ridge will then remain over
the area into early next week. This will provide dry weather,
light winds and warmer temperatures.
&&
.AVIATION...
Areas of MVFR with local IFR over interior NorCal next 24 hrs.
Isolated LIFR over the mountains. Isolated thunderstorms possible
thru 06z Tue. Snow levels at or above 5000 feet. In the Sacramento
Valley, widespread southerly surface wind 10-20 kts with local
gusts to 30 kts thru 00z.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 4 AM PST Tuesday for Burney Basin /
Eastern Shasta County-West Slope Northern Sierra Nevada-Western
Plumas County/Lassen Park.
Flood Watch through late tonight for Carquinez Strait and Delta-
Central Sacramento Valley-Motherlode-Northeast
Foothills/Sacramento Valley-Northern Sacramento Valley-Northern
San Joaquin Valley-Southern Sacramento Valley.
&&
$$
Area Forecast Discussion
National Weather Service Tulsa OK
930 PM CST Mon Feb 5 2024
...New SHORT TERM...
.SHORT TERM...
(The rest of tonight)
Issued at 930 PM CST Mon Feb 5 2024
Surface ridge axis continues to build into central and eastern
Oklahoma this evening, allowing for good radiational cooling
conditions overnight tonight. Lows will dip below freezing for
many areas along and north of I-40 overnight tonight, with more
scattered freezing temps south of I-40. The saturated ground, calm
winds, and clear skies will also allow for some patchy fog
development late tonight into tomorrow morning. Currently, better
conditions look to stay west of the area across central Oklahoma,
but portions of northeast Oklahoma could see some dense fog form
after midnight. Locations along and west of Highway 75 in
northeast Oklahoma have the highest chances nearer the ridge axis
and as temperatures cool well below crossover temps from
dewpoints this afternoon. From Tulsa eastward, more widely
scattered fog is expected, mainly in valley locations. As such
will continue with patchy fog mention areawide for overnight as
confidence still isn`t high enough in greater coverage to increase
fog mentions at this time. Otherwise, the going forecast remains
in good shape, with minimal updates made to accommodate the latest
obs and trends.
Bowlan
&&
.LONG TERM...
(Tomorrow through Monday)
Issued at 209 PM CST Mon Feb 5 2024
Ridging aloft will build over the area Tuesday with upper level
flow becoming southwesterly by Wednesday. Result will be a quick
return to south winds beginning Tuesday, with a more notable
increase by Wednesday, along with a gradual warming trend.
Guidance is in good agreement with a positive tilt upper trough
moving out of the Rockies to our north by Thursday with low level
winds veering and much above normal temperatures.
This period will be marked by an uptick in fire weather
conditions as drier dew points are expected to mix eastward,
potentially dropping RH values below 30% in parts of northeast OK.
Wind gusts close to advisory levels also supported by current
data. Fuel conditions are not too concerning at the moment as ERC
%-iles remain low, however this will be the most favorable
alignment of fire weather conditions in several weeks and would
support high grassland spread rates. Friday also appears to be a
warm day but this time with considerably lighter winds as the sfc
gradient weakens with the presence of a weak sfc boundary.
Uncertainty remains high into the weekend as another Pacific
system could move into the plains. However, model consistency
still lacking and ensemble spread is high. The overall idea
remains a downward trend in temps and upward in precip chances,
and will continue to follow the blended guidance.
&&
.AVIATION...
(00Z TAFS)
Issued at 526 PM CST Mon Feb 5 2024
Main aviation concern will be the potential for patchy dense fog
late tonight into Tuesday morning. Latest HRRR runs showing the
best potential for dense fog development across portions of northeast
Oklahoma. This seems reasonable given previous heavier rainfall/light
winds and limited mixing expected. Went ahead and forecast TEMPO
LIFR conditions at KBVO given forecast low temperatures will likely
fall several degrees below crossover temp/afternoon dewpoint, including
favorable low level sounding profiles. More uncertainty at KTUL/KRVS
and therefore stayed with TEMPO IFR conditions for now. Patchy fog
also possible at SE OK/NW AR terminals, but confidence is again
lower in those areas.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 32 59 43 63 / 0 0 0 0
FSM 35 62 39 65 / 0 0 0 0
MLC 31 63 42 65 / 0 0 0 0
BVO 27 59 39 63 / 0 0 0 0
FYV 29 63 36 63 / 0 0 0 0
BYV 32 60 38 60 / 0 0 0 0
MKO 32 59 42 61 / 0 0 0 0
MIO 30 60 41 61 / 0 0 0 0
F10 32 61 42 61 / 0 0 0 0
HHW 35 62 40 63 / 0 0 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...None.
AR...None.
&&
$$
SHORT TERM...04
LONG TERM....14
AVIATION...12