Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/09/24
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
906 PM CDT Sun Sep 8 2024
.KEY MESSAGES...
- Dry conditions will continue through mid-week.
- Above average temperatures for the next several days, with
highs/lows running about 10 to 20 degrees above normal.
&&
.UPDATE...
Issued at 905 PM CDT Sun Sep 8 2024
Current forecast is on track, therefore no changes made at this
time.
&&
.SHORT TERM /THIS EVENING THROUGH MONDAY NIGHT/...
Issued at 352 PM CDT Sun Sep 8 2024
The main forecast challenges in this period will revolve around
temperatures and potential impacts wildfire smoke aloft may have on
them. The forecast area has seen plenty of sunshine again today with
very mild temperatures in the 70s and 80s. We have seen a batch of
wildfire smoke aloft basically stagnant or trapped over parts of our
CWA from around the Leola Hills area southeast into the James Valley
into east central SD. So, this has put a veil on the sunshine so to
speak. Temperatures haven`t really responded through the daytime as
we anticipated they might. Perhaps some of this is due to the smoke
aloft but low to mid level flow isn`t all that strong either, so we
haven`t seen much in the way of warm air advection take place.
Nevertheless, there really hasn`t been much of an impact on overall
conditions. We`ll likely see some of the this smoke aloft to stick
around through the evening, but it is anticipated to thin and/or
move back to the east and southeast. A sfc high pressure ridge
remains extending into eastern SD and western MN this afternoon and
will likely continue into tonight. This will set up another quiet
overnight with mainly clear skies and mild temperatures. Temperature
readings will not be quite as cool by tomorrow morning with lows in
the mid to upper 50s.
An upper ridge will also remain present overhead across the Dakotas
tonight. This will continue to aid in delivering persistent dry
conditions to our area through most of this period. Temperatures on
Monday are expected to be very warm to hot considering the time of
year we are in. Flow at the sfc and aloft is expected to pick up a
bit more by Monday afternoon which should help to draw in a warmer
air mass. Latest runs of the HRRR smoke product show a higher
concentration of smoke aloft across the western CONUS will shift
east into the Dakotas on Monday. This is progged to begin to move
into our western zones closer to midday and afternoon before
continuing eastward with time later in the day through the end of
this period. It remains to be seen how much this could have an
effect on afternoon temperature readings. Perhaps it will somewhat
but the incoming warmer air mass could overcome any impact. Ensemble
probs for reaching or exceeding 90 degrees on Monday remain the
highest across the Missouri Valley and points west, especially west
river. So, have tailored tomorrow`s highs accordingly to this. An
upper trough progged by guidance is anticipated to crash over the
top of the upper ridge late Monday into early Tuesday. This may
bring a slight chance for an isolated shower or storm across north
central SD. Although, not too confident in this coming to fruition
and BUFKIT soundings in that area are very dry in the low to mid
levels.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 352 PM CDT Sun Sep 8 2024
The upper pattern transitions from zonal flow overtop of a ridge,
with an initial weak wave traversing the Dakotas, to a southwest
flow regime as an upper low over the western CONUS briefly deepens
before lifting northeast as it becomes an open wave. The ridge over
the eastern CONUS hints at becoming a block as a tropical system
meanders across the southeast CONUS, which essentially keeps us in
southwest flow or under the western extension of the upper ridge
into next week, but by this point confidence in the upper pattern is
decreasing as deterministic guidance show variations on the overall
regime and there is a wide disbursement of the days 5-7 clusters.
The initial wave Tuesday still looks to pull in some elevated mixed
moisture associated with the Desert Southwest Monsoon, with warm
advection aiding in elevated convective development. The issue is
the height of this moisture still remains above 10kft, meaning a
deep dry layer and limited depth will probably still only result in
virga showers. NAM BUFKIT profiles even suggest this occurring above
the freezing level, so could even consider a dry-microburst risk. As
an aside, there is a good signal with zonal flow that smoke from
western wildfires will also get pulled into the region, but this is
aloft and not near surface smoke.
Otherwise, heat in the mid levels will steadily ramp up, with
850/700mb temperatures running generally about a standard deviation
above climo through Friday. Still some uncertainty, but for the mid-
range there is good consensus on highs/lows with the greatest spread
on Wednesday with a 25th/75th range of 4-7 degrees, and closer to 3-
5 degrees Tuesday/Thursday before the aforementioned wave and
divergences in solutions begins to influence temperature outcomes.
The main take-away here is that NBM forecast temperatures are about
10 to 20 degrees above normal through the week.
The surface pattern will feature a weak boundary over central South
Dakota early Tuesday, with generally weak flow. Canadian air will
trickle into North Dakota and thus the aforementioned spread in
highs/lows Wednesday, with the surface flow tacking towards easterly
and then southeasterly as a lee low develops to the west. As this
low deepens, the gradient increases, with around 8-12mb across the
state (again, uncertainty is on the increase when this begins to
occur). The end result, and the main forecast concern before
precipitation moves in will be the fire weather potential with the
continued above normal temperatures, relatively low humidity with
NBM dewpoints generally between 50 and 60 degrees, increasing
southeast winds and ambient dry conditions and desiccating
grasses/crops.
As for precipitation chances, and again will need to re-iterate
uncertainty on the increase, the surface trough will outrun upper
level forcing with the wave headed northeast across the western
Dakotas, and into a CAP with deterministic 700mb temperatures above
+10C. NBM continues to downward trend POPs Thursday/Friday.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 622 PM CDT Sun Sep 8 2024
Terminals KABR,KATY,KPIR,KMBG
VFR conditons will prevail across the area tonight and through the
day Monday. Smoke aloft currently over the eastern part of the
region will slowly dissipate tonight, but will see another layer
of smoke aloft move over central South Dakota Monday afternoon.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...Parkin
SHORT TERM...Vipond
LONG TERM...Connelly
AVIATION...Parkin
AREA FORECAST DISCUSSION
National Weather Service Albany NY
1031 PM EDT Sun Sep 8 2024
.SYNOPSIS...
Isolated to scattered showers will diminish early this
evening with cool conditions and variable clouds overnight. A weak
disturbance will bring a chance of showers and isolated
thunderstorms tomorrow. Fair and dry weather returns on Tuesday with
seasonable temperatures with high pressure bringing above normal
temperatures through the week and into next weekend.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
.UPDATE...Few changes were needed with this update as the
forecast remains on track. Minor adjustments were made to the
temperatures and sky cover to reflect latest obs and trends, but
all else remains unchanged. Additional details on tonight`s
forecast can be found in the previous discussion below.
.PREVIOUS DISCUSSION...
As of 358 pm EDT...A closed H500 low continues to move slowly
northeast toward the Gulf of St Lawrence late this afternoon
into tonight. The lake effect and instability showers tied to
the diurnal heating and cold pool will diminish into the early
evening north of the Capital Region.
The winds will diminish and the skies will become partly to
mostly cloudy. Some radiative cooling is possible from the
Capital Region south and east with light winds and some
clearing. Lows will be in the 40s once again with some upper 30s
over the southern Greens, southern Dacks and eastern Catskills.
Some mid and high clouds will increase ahead of the next short-
wave diving into the central and eastern Great Lakes after
06Z/TUE.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
Tomorrow...The short-wave will swing around the base of the mid
and upper level trough over the eastern CONUS. The mid level
lapse rates will remain steep ahead of the disturbance. Sfc
dewpoints will be mainly in the upper 40s to mid 50s. Some weak
instability will be in place with MUCAPEs around 500 J/kg.
MLCAPEs on the CAMs are generally under 250 J/kg. The placement
of the impulse is further south across the region on the 3-km
NAMnest vs the 3-km HRRR and ARW-WRF. We placed a slight chance
of thunderstorms across the forecast area in the afternoon to
early evening. Some may have small hail M&M size or less and
gusty winds, but we do not believe they will severe. SPC has
only "General Thunderstorms" in the forecast for the ALY area.
Max temps were accepted close the ECM MOS with upper 60s to
lower 70s in the valley areas and mid 50s to mid 60s over the
hill and mtns.
The short-wave impulse passes downstream of the area Mon night.
Some lake effect showers may briefly occur. High pressure will
build in quickly from the OH Valley. Some radiational mist is
possible in and near the major river valleys. Lows fall into the
40s to lower 50s.
Tuesday will start the extended stretch of fair and dry
weather. A sfc anticyclone ridges in over NY and New England
with seasonable temps and abundant sunshine. Mid and upper level
height rise aloft. Max temps in the valleys will be in the lower
to mid 70s (a few upper 70s in the mid Hudson Valley) and 60s
over the higher terrain. A good radiative cooling night will
occur Tue night with lows clear/mostly clear skies and light to
calm winds. Some patchy mist/fog is possible again. Lows will be
in the 40s to around 50F.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
An extended period of benign and dry late summer weather is expected
in the extended forecast from mid week into next weekend for eastern
NY and western New England. High pressure will build in at the
surface and aloft over the Northeast by Wed into Thu. A blocking
mid and upper level ridge will build in from the Midwest and Great
Lakes Region over upstate NY and New England by late in the week
into the weekend. Low and mid level heights, as well as H850 temps,
will be about 1 to 2 STDEVs above normal based on latest NAEFS/GEFS
guidance.
Temps will rise from near to slightly above normal readings on Wed
to about 10 degrees above normal by Thu and Fri with with low to mid
80s in the valleys and 70s over the higher terrain. There could be
some upper 80s in the mid Hudson Valley. Lows will be in the 50s to
around 60F. Humidity levels will be moderate with dewpoints in the
50s to lower 60s. The forecast remains dry with above normal temps
with a Rex Block set-up on the weekend, but a back door cold front
may bring some clouds and a slight cool down of temps closer to mid
Sept normals by Sunday.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Through 00z Tuesday...VFR conditons prevail across all terminals
this evening with variable cloud cover across eastern New York
and western New England. Favorable flight rules should prevail
across the terminals for the majority of the 00z TAF cycle,
though some MVFR to IFR patchy fog could develop at KGFL and
KPOU early tomorrow morning courtesy of radiational cooling.
Confidence is higher in this probability at KGFL as recent
rainfall has maintained moist soil conditions and anticipated
breaks in cloud cover will therefore promote ample cooling
processes. However, dry conditions were maintained at KPOU
throughout the last 24 hours so it`s possible that drier soil
conditions could inhibit fog development despite mainly clear
skies.
Any fog that develops should burn off relatively quickly
tomorrow morning, yielding VFR conditions once again. Such
conditions will remain in place into the afternoon tomorrow
before being threatened by scattered showers and possible
thunderstorms. Included PROB30 groups at KGFL and KALB for
afternoon showers to allude this possibility, but confidence
remains low in timing and location of showers tomorrow
afternoon.
Winds throughout the period will be lighter out of the
southwest, ranging from sustained speeds of 5-10 kt throughout
the day tomorrow and from calm to about 3 kt overnight tonight.
Outlook...
Monday Night: Moderate Operational Impact. Chance of SHRA...FG.
Tuesday to Friday: No Operational Impact. NO SIG WX.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...Wasula
NEAR TERM...Gant/Wasula
SHORT TERM...Wasula
LONG TERM...Wasula
AVIATION...Gant
Area Forecast Discussion
National Weather Service Denver/Boulder CO
858 PM MDT Sun Sep 8 2024
.KEY MESSAGES...
- Warm again Monday with 10-30% pops, highest over the mountains.
- Above normal temperature trend continues through the upcoming
week. Mostly dry across the area all week other than low chances
(10-40%) for showers and thunderstorms across the mountains.
- Best chance (20-50%) for showers and thunderstorms will be
Wednesday afternoon and evening, including 20% across portions
of the plains.
&&
.UPDATE...
Issued at 842 PM MDT Sun Sep 8 2024
The latest radar scan shows showers have diminished across the
CWA. Little adjustments were made to the current forecast. Contemplated
adding some smoke into the northeastern portion of the state as
the HRRR Vertically Integrated Smoke was picking up on the plume
from the many fires burning across Idaho and Montana making its
way into the area via the northwest flow aloft. However, the
highest concentrations have migrated eastward at this time, so
decided to keep it out for now. Everything else looks good for the
current forecast to remain on track.
&&
.SHORT TERM /Through Monday/...
Issued at 240 PM MDT Sun Sep 8 2024
Area radars are showing widely scattered convective coverage over
the mountains, high valleys and foothills at this time. There is
isolated coverage over the plains south of I-70 as well. What rain
is falling is pretty light. Most of the plains have dew points in
the 30s F to mid 40s F at this time, with some 50s F over the
northeast corner.
Models keep the upper ridging over the CWA tonight and Monday. The
QG Omega fields show weak downward vertical velocity for the CWA
later tonight through Monday morning. Precipitable water proggs
show values in the 0.40 to 0.80 inch range for the CWA tonight and
Monday. Surface dew points are in progged in the 30s and 40s over
the plains on Monday. Concerning instability, there is limited
CAPE progged for Monday afternoon, with the highest values over
the far northeast corner. Will go with 10-30% pops late day
Monday; greatest over the high country.
It has reached 89 F at DIA so far this afternoon for a high. For
Monday`s highs, thickness grids show readings about 0.5 - 1.5 C
warmer then this afternoon`s.
&&
.LONG TERM /Monday night through Sunday/...
Issued at 219 PM MDT Sun Sep 8 2024
For Monday evening through Wednesday, upper level ridge across
the southwest part of the country begins to shift eastward Tuesday
as an upper level trough approaches the west coast. Warm
temperatures will continue Tuesday under this pattern with another
+90F high temperature for Denver very likely. Precipitable water
values will be around a half inch (100-120% of normal) over the
higher terrain and three-quarters inch (near normal) across the
plains Monday evening through Tuesday. SBCAPE climbs up to 500
J/kg in places. Because of this, expect to see isolated to
scattered showers and thunderstorms over the higher terrain. Some
of these should progress eastward onto the nearby plains. Subcloud
layer over the lower elevations will be dry, so expect most or
possibly all of the rainfall to be light across the lower
elevations Monday evening and Tuesday. The 12Z NAM, GFS, and
Canadian, all show weak convection along the Palmer Divide and
into Lincoln County late Tuesday. Will increase PoPs for this. On
Wednesday, a short wave trough lifts northeast across the region
and should increase the amount of showers and thunderstorms. There
will be an uptick in moisture as well helping to increase chances
for precipitation. With the increase in moisture and clouds,
temperatures take a step back, but remain above normal with highs
reaching the mid to upper 80s over northeast Colorado.
Southwest flow aloft ramps up Thursday and Friday as the upper
level low/trough tracks east across the Pacific Northwest,
Northern Rockies, and by Friday the Northern Plains. This pulls
drier desert air into the area. Expect temperatures to top 90F
across most of northeast Colorado. A lee side surface trough forms
east of the Rockies, resulting in gusty south winds. On Friday,
some lift will be over Colorado as the main trough passes north of
Colorado. Limited moisture will make it difficult for showers and
storms to develop, but enough for a slight chance over the
northeast plains.
For next weekend, another upper level trough moves onto the west
coast and induces ridge over the Central Plains. This will bring
southwest flow aloft to Colorado. Temperatures cool a little, but
stay above normal with highs in the lower to mid 80s over
northeast Colorado.
&&
.AVIATION /00Z TAFS through 00Z Tuesday/...
Issued at 535 PM MDT Sun Sep 8 2024
VFR conditions are expected through the TAF period. Afternoon
convection today has lead to some outflow boundaries currently
heading towards all Denver area TAF sites. These VRB and gusty
winds are expected to last until the environment stabilizes in
the next few hours. Winds are then expected to transition to a
more diurnal SSW pattern for the overnight hours. Confidence is
high that tomorrow will see similar conditions to today, with
high- based afternoon showers bringing gusty outflows to all
Denver TAF sites.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Bonner
SHORT TERM...RJK
LONG TERM....Meier
AVIATION...Bonner
Area Forecast Discussion
National Weather Service Quad Cities IA IL
610 PM CDT Sun Sep 8 2024
.KEY MESSAGES...
- Upper level smoke will linger into Monday.
- Quiet pattern for much of the week with temperatures warming
above normal.
- NBM is mainly dry over the weekend, but uncertainty with the
the track of tropical remnants and likely development of a
blocking ridge in the eastern CONUS leads to overall low confidence.
&&
.SHORT TERM /THROUGH MONDAY/...
Issued at 218 PM CDT Sun Sep 8 2024
N/NW flow aloft will continue to funnel upper level smoke down into
the area into Monday. Based on the HRRR vertically integrated
smoke it looks like the greatest coverage will be across the
northeast half of the service area. With the smoke remaining aloft
we`re not anticipating any impacts at the surface, but it should
make for a colorful sunset tonight and sunrise on Monday for some.
Otherwise, tranquil conditions will persist as mid level ridging
builds into western Great Lakes. For tonight, weak surface winds and
dry air will provide another favorable night for diurnal cooling
with lows likely closer to blend of 10th & 25th percentile of NBM
and ranging from the lower 40s to around 50. Not quite as chilly as
those of this morning (a few upper 30s with widespread lower 40s),
but still seasonably cool. We may also see some patchy fog develop
once again in the river valleys and low lying areas. Warm advection
on Monday, with 850 hPa temperatures soaring into the range of 16c
to 19c, coupled with a favorable warm SW surface wind component will
support highs several degrees warmer over those of today. Given all
the above along with the dry ground and thinning upper level smoke
I favored near a blend of 75th & 90th percentile of NBM with highs
in the low to mid 80s.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
Issued at 218 PM CDT Sun Sep 8 2024
Broad upper level ridging will largely dominate through the
rest of the week leading to a continuation of dry conditions and
above average temperatures. Broad southerly flow and warming
low/mid level temperatures will boost highs well into the 80s
area-wide, and possibly near 90 for some Thursday and Friday.
Dew points are forecast in the 50s/around 60 so humidity should
not be a factor staying fairly low. Lows at night should cool
off into the 50s to around 60 with decoupling. A weak shortwave
trough is depicted to move through the region Tuesday and
Tuesday night. The main low level jet and any moisture advection
looks to focus from portions of Kansas to northern Wisconsin,
thus limiting any rain chances, albeit still low with Gulf
moisture lacking, well to our north/west.
By late week and next weekend, uncertainty between the track of
a remnant tropical system from the Lower Mississippi Valley and
an expansive blocking ridge across the eastern CONUS leads to
overall lower forecast confidence, particularly with precipitation
chances and temperatures. The blocking ridge centered over the
eastern Great Lakes and Ohio Valley could act to keep the
tropical remnants stalled/suppressed to our south/east and also
slow/weaken an ejecting western trough. Should this occur the
result would likely be a continuation of mainly dry weather and
above average temperatures, which is in line with the latest NBM.
If the blocking ridge is weaker or displaced further north/east
this could allow for some precipitation potential with a more
northwesterly drift of the tropical remnants fostering more
moisture. To this idea, the ECS and GEFS ensemble probabilities
are 30-40% for 24 hr QPF >=0.01 inch Friday and Saturday particularly
across the south/east service area.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 608 PM CDT Sun Sep 8 2024
VFR conditions are expected to be in place through the period,
while periods of upper level smoke continue to move down across
the area making for hazy skies, but not expecting any impacts
at the surface. Patchy river valley fog is possible again late
tonight and early Monday morning (09-13z). Confidence is too low
on occurrence/impact at the river sites (DBQ, MLI, BRL) and
thus left out mention.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.
&&
$$
SHORT TERM...McClure
LONG TERM...McClure
AVIATION...Ervin
Area Forecast Discussion
National Weather Service Sioux Falls SD
1049 PM CDT Sun Sep 8 2024
.KEY MESSAGES...
- Smoke is moving into the region on upper level winds. Expect
skies to be partially obscured by smoke through at least
Tuesday.
- A mostly dry forecast expected for this week, with above
average temperatures.
- Next chance for widespread showers and thunderstorms is Friday
night into Saturday. Details remain uncertain at this time.
&&
.DISCUSSION...
Issued at 224 PM CDT Sun Sep 8 2024
An upper ridge continues to build in and then flatten out slightly
over the next 24-48 hours. This flow pattern will usher in more
smoke from wildfires over the western United States and Canada.
Smoke will result in milky looking skies, especially Tuesday when
thicker smoke is expected to arrive. While most of the smoke will
remain aloft, some minor air quality impacts may be noted at the
surface. Sensitive populations will want to keep aware for the next
few days.
Tonight, lows will dip into the 50s. Monday will continue the
warming trend we started Sunday. Temperatures at 850 to 700 mb are
in the 90th percentile for climatology per the ESATS tables. Good
mixing will bring these warmer temperatures down, helping bolster
surface temperatures for Monday. Highs expected to reach the mid 80s
along and east of the I-29 corridor, and upper 80s to the west. Some
90s are possible in south central South Dakota, but due to smoke
aloft, confidence in breaking 90 degrees is low. In addition,
cluster analysis indicates only a 10-40% probability of breaking 90
degrees. Taking all this into consideration, have knocked the area
of possible 90 degrees back a bit from the NBM. Monday afternoon a
weak mid-upper wave approaches from the west, tightening the SPG as
it does. Winds will continue to be out of the south, increasing in
the afternoon. Gusts 20 to 25 mph are expected west of I-29 and will
continue overnight into Tuesday morning. There is a low chance for
some showers Monday night into Tuesday morning, but model soundings
are all dry and well capped. Any instability is elevated above 10
kft, so much more than sprinkles will be difficult to generate.
Overnight lows will be warm, in the low to mid 60s.
As Tuesday morning progresses, the wave continues to move east, and
so will the strongest wind gusts. By Tuesday afternoon gusts 25 to
30 mph are expected from the James River eastward, decreasing
rapidly after sunset. A strong area of subsidence follows the wave,
pushing 850 mb temperatures into he 97th percentile for climatology.
While mixing isn`t expected to be as deep as Monday, the subsidence
combined with continued southerly flow will usher in widespread high
temperatures into the mid to upper 80s, with the possibility of
90s again west of the James River. Cluster analysis indicates a
slightly higher probability (40-50%) of breaking 90 degrees in
this area. However, uncertainty in 90 degree temperatures is
again high due to the thick smoke indicated in the HRRR and RAP
models. As such, have again limited the coverage of NBM 90
degree temperatures. Lows will be warm in the low to mid 60s.
Wednesday, the upper ridge will strengthen and the SPG at the
surface will tighten in response. Highs will be similar to the past
couple days with widespread upper 80s with a low probability (30%)
of breaking 90 degrees. Meanwhile, a strong upper trough will be
digging over the Pacific Northwest. As it progresses eastward
Thursday, winds will increase with gusts Thursday afternoon peaking
around 30-35 mph. West of the James River gusts could even approach
40 mph. Highs Thursday will be cooler in the mid to upper 80s.
Friday the trough begins to traverse the region. This system is
expected to bring the next chance for widespread showers and
thunderstorms. Current model runs have the system taking a more
northerly track, but high variance in model solutions leaves
confidence in any one solution low at this time. The most likely
timeframe for showers and storms will be Friday night into
Saturday. A break Sunday followed by a more active pattern for
next week has the potential to bring more shower chances.
&&
.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1044 PM CDT Sun Sep 8 2024
Smoke layer aloft will impact our forecast area through much of
this forecast period, though exact coverage and height of the
smoke layer is low confidence.
VFR conditions will prevail, with mostly clear skies (aside from
the smoke layer) into Monday morning, then scattered mid-level
clouds at or above 10kft AGL possible from midday Monday onward.South
to southeast winds generally at or below 10kt through sunrise
Monday, with gusts 18-25kt developing after 15Z Monday.
Gusts may subside with sunset Monday evening, but if boundary
layer decouples, low level jet could result in marginal low
level wind shear. Confidence in strength of the low level wind
shear is not high enough to include in this TAF forecast, but
may be considered for later updates.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.
&&
$$
DISCUSSION...AJP
AVIATION...JH
Area Forecast Discussion
National Weather Service Goodland KS
928 PM MDT Sun Sep 8 2024
.KEY MESSAGES...
- Low chance (less than 15%) of showers/storms this evening and
overnight. Severe weather is not expected.
- Above normal temperatures are forecast to continue through the
week.
- A storm system bringing gusty to strong winds resulting in
fire weather concerns mid through late week.
&&
.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 135 PM MDT Sun Sep 8 2024
Northwest upper level flow continues across the area as ridging
across the western CONUS continues. Mid to upper level smoke remains
maintaining the hazy look to the clouds; 12Z run of the HRRR
Vertically Integrated Smoke suggests that this should begin to
come to an end tomorrow as the western CONUS ridging begins to
break down. An overall similar day to yesterday is expected for
the remainder of the afternoon as SSE winds look to be around 10
knots with occasional wind gusts up to 20-25 mph.
Heading into this evening and overnight, any precipitation signals
have virtually disappeared compared to what I was seeing 24
hours ago. If storms would be able to develop eastern Colorado
would be most favorable for development, additional storms that
are currently across the Front Range may be able to make it into
western portions of Kit Carson county before dissipating this
evening. Severe weather is not expected, although some gusty to
locally strong winds would be the main hazard. Do agree with the
previous shift that some sprinkles may be able to develop
overnight mainly for north of Interstate 70 as a strong 40-45
knot LLJ develops. I used the NAM 700-500mb moisture to indicate
the ares that favor the sprinkles.
Monday, the western ridging begins to break down, a surface trough
develops across the eastern portion of the CWA allowing the pressure
gradient to tighten again leading to the development of breezy
winds. To the west of the trough winds look to be light around 10
knots. The main question for the day is which direction will the
winds be blowing will it be more southerly (~180 degrees) or will it
be more SSW (210-230 degrees). If its the latter then temperatures
will exceed 95 degrees (as that direction can be considered more of
a "heater" wind which climatologically does favor temperatures
to increase more. As of now the only guidance that is suggesting
this is the HRRR and RAP, will be interesting to see if other
guidance starts trending this way. This is a significant
mesoscale feature as if it were to happen then near critical to
locally critical fire weather may become a concern along and
east of a Red Willow to Thomas county line as winds are
currently forecasted to gust around 25-30 mph.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 135 PM MDT Sun Sep 8 2024
The extended period continues to show strong signals of temperatures
remaining well above normal with highs in the 90s and little relief
overnight. Tuesday currently appears to be the least active of the
week as the region will be in between systems with light winds
currently forecasted. Some weak moisture advection may lead to some
shower and storm development along and south of I-70 across eastern
Colorado during the evening hours.
Wednesday, will see a upper level trough begin to take shape across
the western CONUS. The low level wind field will also begin to
increase as well which will begin the first of multiple days of fire
weather concerns as winds will begin to ramp up during the late
morning hours with gusts of 25-35 mph currently forecasted.
Thursday will see the trough begin to deepen which will tighten the
pressure gradient across the area as southerly winds are currently
forecasted to gust 35-45 mph across the area there is potential
as well for gusts across eastern Colorado to reach the 50 mph
range. Near critical to critical fire weather conditions remain
a concern for areas along and west of Highway 25, the main
question will be how far east will the drier air push; this will
all depend on the positioning of the trough.
Into Friday the trough will push to the north as winds wont be as
intense as Thursday but will still be gusty around 30-40 mph
resulting in another day of fire concerns. Overall there area still
some considerations that need to be taken into account. 1) The
overall track and location of the trough. If it can further
deepen and take a more southerly track then drier air than
forecasted will move into the area. 2) A tropical disturbance in
the Gulf of Mexico. How will this affect the overall synoptic
pattern and how will it impact moisture quality as well.
Storm chances with this system don`t appear as likely based on the
current northward path that guidance is suggesting plus the tropical
system perhaps pulling moisture away from the region won`t help
either. Nevertheless the potential remains for an active mid to late
work week across the region.
Later in the weekend and into the following week (just outside of
this forecast period) deterministic and now even ensembles are
latching out to a potentially stronger trough that may have some
severe potential, wind, fire and dust potential all with it. It`s
way to far out to jump to any conclusions at this time plus a lot
most likely will change with details but there are signals that the
active pattern will continue.
&&
.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 926 PM MDT Sun Sep 8 2024
Both terminals will see VFR conditions through the forecast
period. The passage of a low level jet will create wind shear
at both terminals from 06z to about 13z-15z Monday at
190@40-45kts.
Winds for KGLD, south 10kts through 13z, then becoming south-
southwest around 10-20kts. strongest gust potential from 18z
Mon-00z Tue. By 00z Tuesday, shifting southeast.
Winds for KMCK, southeast around 10kts through 09z Monday, then
light/variable. By 15z, becoming south 10-20kts with strongest
gusts from 18z Mon-03z Tue.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.
&&
$$
SHORT TERM...Trigg
LONG TERM...Trigg
AVIATION...JN
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
957 PM EDT Sun Sep 8 2024
.SYNOPSIS...
High pressure and a dry airmass will remain in place across the
region through mid week.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Northwest flow aloft with a large area of surface high pressure
over the Ohio Valley. Continue to observe a fair amount of
smoke aloft across the area which will likely continue to drift
southeast overnight into Monday.
Otherwise, with high pressure centered over the area, skies will
be mostly clear with light winds. Expect another cool night with
lows generally in the lower to middle 40s, although a few upper
30s will be possible in outlying typically colder areas. Also,
some areas of river valley fog will be possible late tonight.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
The surface high will remain centered over the Ohio Valley
Monday through Monday night. The HRRR smoke model is showing
the potential for some additional smoke aloft to drop down
across the area on Monday so this could lead to some filtered
sunshine at times during the day. Otherwise, expect mostly
clear skies to prevail. Temperatures will continue to moderate
with highs on Monday in the upper 70s to lower 80s. Lows Monday
night will be in the upper 40s to lower 50s.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A prolonged period of dry weather will continue through the early
part of the long term as high pressure settles slowly across the
Eastern CONUS. There will be a chance for some relief from the
drought conditions starting Friday with the possibility of
increasing moisture and forcing associated with a developing
tropical system over the Western Gulf. Right now the model blend
suggests chances for showers and thunderstorms mainly over southern
locations from Friday through Sunday. Later model runs will better
pinpoint the potential effects from this system that is forming over
waters east of Texas.
High temperatures begin in the mid and upper 80s Tuesday, increasing
to around 90 Wednesday and Thursday in the warm circulation around
the high pressure. A retreat due to possible clouds and precip is
indicated for Friday through Sunday, when highs are forecast to
range from the upper 70s to mid 80s.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Surface high pressure will remain in control of the weather
through the period. This will lead to dry weather, mostly clear
skies, and light winds. Some fog development will be possible
late tonight - mainly in the river valleys. Have MVFR to IFR
vsby restrictions at KLUK valley location late tonight into
early Monday morning. Fog will burn off quickly Monday morning
with only a few fair weather cumulus clouds and continued high
level clouds.
OUTLOOK...No significant weather expected.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...JGL
NEAR TERM...AR
SHORT TERM...JGL
LONG TERM...Coniglio
AVIATION...AR
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
801 PM CDT Sun Sep 8 2024
.KEY MESSAGES...
- Temperatures climb the next several days, turning much warmer by
the middle of the week.
- An extended period of dry weather appears likely until possibly
late in the week or weekend as a remnant tropical system lifts
toward the area.
&&
.UPDATE...
Issued at 801 PM CDT Sun Sep 8 2024
Temperatures are falling a bit quicker than expected early this
evening as clear skies (but hazy due to smoke from distant
wildfires) allow good radiational cooling. High pressure centered
nearly overhead is allowing for lighter winds than yesterday as
well, limiting any mixing that would help keep temperatures from
falling rapidly. Nighttime lows should approach last night`s low
temperature values given the similar air mass and good radiational
cooling setup. Have therefore lower temperatures a degree or two
for tonight, with generally mid 40s lows expected.
37
&&
.DISCUSSION...
Issued at 213 PM CDT Sun Sep 8 2024
Surface analysis early this afternoon depicts high pressure centered
over central Illinois, keeping things cool and dry to close out the
weekend. Sunshine is filtered due to wildfire smoke/some high
cirrus, which is noted on satellite imagery from North Dakota
southward into southern Illinois/Indiana. The HRRR smoke model shows
these concentrations continuing through the remainder of today, with
thicker amounts sinking south across the area overnight into Monday.
Manually adjusted the sky cover grids to account for the hazy, smoky
skies through much of Monday.
The surface high will slowly start to push east of here on Monday as
upper ridging begins to work into the central CONUS. Temperatures
will climb the next few days, becoming much warmer by midweek as
upper ridging builds further east and amplifies. High temperatures
by Wednesday and Thursday will approach or exceed or 90 degrees.
There is a 20-50% chance (NBM) that temperatures will exceed 90
degrees on Wednesday, with lesser chances on Thursday. A drier
airmass will keep heat indices near the air temperature, though
the abnormally warm temperatures could still pose a limited threat
to those who have sensitivity to heat. Temperatures drop a few
degrees by next weekend, but still remain warmer than normal
through the extended period.
Dry weather will continue through much of the week as we remain
locked underneath amplified flow aloft. Guidance continues to show
the remnants of a tropical system lifting toward the Ohio Valley
late in the week or weekend, possibly bringing our next chance for
rain. Blended ensemble guidance shows <30% chance for 0.25" of
rain through the weekend, which would do little to improve our
ongoing precipitation deficit especially in southern Illinois.
NMA
&&
.AVIATION... (For the 00z TAFs through 00z Monday Evening)
Issued at 611 PM CDT Sun Sep 8 2024
Mostly cloud free skies are expected over the upcoming 24 hours,
however periods of smoke aloft are expected to produce hazy skies.
Otherwise, high pressure at the surface shifting slowly
southeastward will allow southwest winds to spread over the area,
becoming 4-8 kts by Monday afternoon.
37
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Louisville KY
907 PM EDT Sun Sep 8 2024
.KEY MESSAGES...
* Fair weather this afternoon and Monday with one more chilly
morning. Some filtered sunshine Monday with mid-level smoke from
Canadian fires dropping southeast into our area.
* Overnight lows tonight will dip into the 40s. Temperatures in the
low to mid 40s could approach or break low temperature records at
Lexington and Frankfort.
* Dry weather is expected through Wednesday night. A tropical
system is expected to bring showers to the region Thursday night
through much of next weekend. Forecast confidence on rainfall
amounts remains below average at this time.
&&
.UPDATE...
Issued at 907 PM EDT Sun Sep 8 2024
Hazy skies will continue through the overnight hours as some smoke
from Central Canada drifts over the region. Most of the mesonet
sites have already dipped into the upper 50s, therefore, have
lowered Min Ts over the region by about a degree. Models are still
showing quite a bit of uncertainty with Min Ts for Monday morning.
It is unclear how much the upper level smoke will prohibit cooling.
However, still have a good shot at seeing temperatures similar to
the previous morning in the low 40s and a decent shot at breaking or
getting close to record low temperatures. Have added some thin,
patchy fog in the river valleys given persistence, light winds, and
mostly clear skies. Otherwise, the current forecast remains on track
with high pressure and pleasant fall conditions.
&&
.SHORT TERM /THROUGH MONDAY/...
Issued at 250 PM EDT Sun Sep 8 2024
Very dry airmass in place for this time of the year, with 12Z
Nashville sounding showing a precipitable water of 0.46", very close
to the min for this date. Unfortunately the brilliant blue skies of
yesterday appear to have taken on a hazy form, with latest Smoke
HRRR model showing some smoke aloft dropping down from central
Canada. GOES Natural Color imagery is showing this haze, being a
littler thicker now over central IL/IN/OH, and that area is headed
southward. Expect the hazy skies to continue this period.
Otherwise, no concerns in this forecast cycle. Surface high pressure
centered just to our northwest will wobble to a position over the
mid Ohio Valley by tomorrow afternoon, bring very light and variable
winds. Expect another cool night. Temperature comparisions from this
morning to tomorrow will depend on how the balance between calm
conditions works with that smoky layer aloft. For this package, will
lean towards it being 1-3 degrees warmer for most locations, with
coldest spots likely in the low-mid 40s. Highs tomorrow under that
filtered sunshine should be several degrees warmer than today, as
low-level thicknesses quickly increase. Should be in the low to mid
80s for most.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
Issued at 250 PM EDT Sun Sep 8 2024
Monday Night through Wednesday Night...
Upper troughing over the Ohio Valley currently is forecast to lift
well off to the northeast by Monday night with heights building
across the area in its wake. The flow pattern is forecast to remain
unremarkable with dry and tranquil weather expected through the
period. Lows Monday night will generally be in the very low 50s
across much of the area. A few of our deeper valley locations
probably will drop into the mid-upper 40s. Temps will rebound
rather quickly on Tuesday with highs in the mid-upper 80s and lows
Tuesday night in the low-mid 50s. As heights continue to build on
Wednesday, we should see most locations get into upper 80s to around
90 for highs. Lows Wednesday night look to drop back into the upper
50s and lower 60s.
Thursday through Sunday...
By mid-week, large scale hemispheric pattern will find mainly zonal
flow over the northern CONUS. A well advertised tropical cyclone
should be in progress in the northwest Gulf. This cyclone, may make
a landfall somewhere in the LA area late Wednesday/early Thursday.
The multi-model consensus continues to tighten up here with all
three (GFS/CMC/Euro) tracking the system northward along the MS
River and having it located in NE AR by Friday morning. Given the
multi-model consensus, it appears this system will bring much needed
rainfall to the region beginning as early as Thursday afternoon and
continuing through the weekend as the system may end up stalling out
across portions of the TN/OH Valleys.
QPF amounts from the models still contain substantial uncertainty
and contain a large amount of spread. The Canadian is the wettest
of the bunch suggesting several inches of rain being possible. The
GFS and Euro are not as robust as the Canadian, but offer some
helpful QPF for our drought areas. Overall, forecaster confidence is
a bit higher than 12 hours ago with regards to seeing some QPF, but
confidence in amounts (at days 5-7) remains below normal.
Highs on Thursday should feature a gradient with warmer temps up
across southern IN and northern KY where lesser amounts of cloud
cover will be found. Highs in the upper 80s look likely here, but
mid 80s will be likely over southern KY. Highs Friday and Saturday
will be quite cooler with expected cloud cover and precipitation
around. Will go with upper 70s to the very low 80s for highs here.
Temps probably will not change too much for Sunday with highs
staying in the upper 70s to the very low 80s.
&&
.AVIATION /00Z TAFS THROUGH 06Z TUESDAY/...
Issued at 716 PM EDT Sun Sep 8 2024
VFR weather expected. Sfc high pressure currently centered over
western IL will drift ESE over the Lower OH Valley tonight. Expect
clear skies and light and variable tonight and Monday.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.
&&
$$
UPDATE...SRM
SHORT TERM...RJS
LONG TERM...MJ
AVIATION...SRM
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
627 PM CDT Sun Sep 8 2024
.KEY MESSAGES...
- There is an expected warming and drying trend that will
feature summer-like temperatures through the week.
&&
.DISCUSSION...
Issued at 200 PM CDT Sun Sep 8 2024
Mid level water vapor imagery shows a clear cinnamon roll low
spinning over southern Quebec east of a ridge over the Great
Plains, keeping northwesterly flow aloft over the Western Great
Lakes. With wildfires burning in Western Canada, this has
translated in upper-level smoke moving over northern Illinois.
The HRRR smoke model has the thickest plume moving overhead
later today and through Monday morning while staying safely
above the ground. As a result, the forecast was updated to
mention partly cloudy skies through at least Monday afternoon to
account for the smoke mixing in with the mid level stratus and
higher cirrus clouds aloft. Temperatures are expected to still
cool through the partly cloudy skies overnight, with lows
tomorrow morning in the upper 40s and low 50s.
As the upper level ridge grows and drifts east through the
week, surface high pressure will develop and park over the
region. Guidance projects a weak embedded wave with a slug of
upper-level moisture ejecting out of the Plains around Tuesday,
but with a lack of instability, it should only translate into
some increased cloud cover. As 850 mb temperatures gradually
move into the upper teens (Celsius) through the week, surface
temperatures will be on the rise for more summer-like conditions
with highs in the upper 80s and isolated areas near 90. The one
bit of uncertainty is how models are handling dew points.
Depending on the degree of mixing each afternoon, there is the
potential for afternoon relative humidity values to dip into the
sub-20 percent range especially during the Monday to Wednesday
timeframe. Dew points were adjusted down, but taking a look
upstream at current obs of dew points in the 30s in southern
Missouri, there is a concern that the dew points/RHs on Tuesday
and Wednesday are still too high. Relatively light winds
(speeds generally in the 10 to 15 mph range) should temper the
overall fire weather threat, although drying fine fuels may
become receptive to increased grass/brush fire starts through
the end of the week.
There is also an eye being kept on the Gulf of Mexico and the
potential development of a tropical system this week. Long range
models have whatever develops moving northward toward the Ohio
River toward the end of the week, though differ on how far
north it can actually reach. For that reason, felt no reason to
change the slight (15 to 24 percent) chance for some showers
advertised by the NBM.
DK
&&
.AVIATION /00Z TAFS THROUGH 06Z MONDAY/...
Issued at 627 PM CDT Sun Sep 8 2024
The only forecast concern is gusty west/southwest winds Monday.
Southwest winds will continue through the period and will
diminish under 10kts with sunset this evening. Low level winds
will steadily increase overnight and its possible speeds may
increase back into the 10-12kt range prior to sunrise along with
a few gusts. These low level winds will be diminishing through
the mid/late morning on Monday, but prevailing gusts are
expected to develop after sunrise, perhaps becoming less
frequent by mid/late afternoon. Speeds are expected to diminish
quickly with sunset Monday evening. cms
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...Small Craft Advisory from 1 AM to 9 AM CDT Monday for the IL
nearshore waters.
&&
$$
Visit us at weather.gov/chicago
Area Forecast Discussion
National Weather Service Spokane WA
308 PM PDT Sun Sep 8 2024
.SYNOPSIS...
Showers will linger over southeast Washington and lower Idaho, as
well as near the Cascades, this evening, with a small risk for
thunderstorms. Mild temperatures will linger through early this
week. Skies will be smoky through early Monday as wildfire smoke
from Oregon and Central Idaho spreads across the Inland Northwest.
A cooler weather pattern, featuring the chance of showers, is
expected Wednesday and Thursday.
&&
.DISCUSSION...
Tonight: The threat of showers and isolated embedded thunderstorms
will be found over some of the region, but as whole the area will
see dry weather. A shortwave will continue to lift across the
region this evening, shifting east into Montana by Monday morning.
Showers will be possible over southeast WA and the central and
southern Panhandle, with a small risk reaching as far north of
southeast Spokane and Kootenai county. Other showers will be
possible near the Cascades and north-central WA. A few t-storms
are possible, with the potential near the Blue Mountains/Camas
Prairie associated with the best lift and instability. A few could
also pop near the Cascades but the risk is small. Overall the
precipitation potential wanes after dark and generally ends
heading into the overnight. Outside of any of the isolated
t-storms, precipitation (if any) looks light.
Wildfires around Oregon and southern and central Idaho will
continue to contribute to some haze around the region, with the
higher concentration over the Palouse into southern Shoshone
county, near to south of I-90 into the Camas Prairie. HRRR
guidance shows this start so decrease a bit this evening, but
another surge of spread across the region later tonight into
early Monday as the shortwave trough shifts through. Then it
starts to decrease throughout the region heading into later
Monday morning and afternoon.
Monday and Tuesday: A weak ridge is squeezed between another
shortwave system moving across Canada, with a jet brushing along
the Canadian border, bringing in the next shortwave later Monday
into Tuesday. A modest westerly flow in this set-up will allow for
dry, breezy conditions Monday. Temperatures will remain above
normal, but are projected to cool relative to Sunday. The
breezy/dry/hot conditions are contributing to fire weather
concerns and the Red Flag Warning in place for portions of the
Upper Columbia Basin/Spokane area and Palouse for winds and low RH
for Monday afternoon/early evening. Otherwise the day looks
precipitation free, with a mix of clouds and sun. By Monday night
the winds wane over most of the region, but will still be breezy
from the north through the Okanogan Valley to western basin.
Clouds being to increase by Monday night into Tuesday too as the
next shortwave pivoting in. Shower chances come to the far
northeast WA and north ID mountains, but for the large part it
will remain dry. Any precipitation that may fall looks light as
the brunt of the moisture and energy stays north of the Canadian
border. Temperatures cool even further Tuesday, still slightly
above normal.
Tuesday night to Thursday: A more notable pattern change occurs
this period as a deeper trough moves into the area. This system
takes a more direct path through the region and taps some of the
available moisture. Precipitation chances start to increase over
the region Tuesday overnight, becoming likely for at least some
of the Wednesday into Tuesday. The highest potential lays
southeast WA and the ID Panhandle and near the immediate Cascade
crest, while the lowest risk will be in the lee of the
Cascades/western basin. The potential for wetting rains (>=0.10")
will be modest around the Panhandle, outside of the typically
drier L-C Valley, with 24-hour potential of wetting rains around
50-80%. In the 48-hour period between Wednesday morning and
Thursday night there will be the potential for a 0.50 to 1.0" of
rain over parts of the ID Panhandle, with that higher end of that
range in the mountains. The eastern third of WA could see 0.10" to
0.40" in that same 48 period, while central WA into the Cascades
is more likely to see trace amounts to less than an tenth of
inch. Precise details are apt to change, but this is the general
potential for now. Some embedded t-storms are also possible, but
the risk is low and at this time anything that may develop at all
look weak. Winds will be a little breezy near the Cascades and
western basin and near and downwind of the Blue Mountains, with
winds gusting near 15-20 mph possible. Temperatures are expected
to be notably cooler with highs around the 60s and 70s, with some
areas struggling to get out of the 50s around the Panhandle
mountains. The warmer readings are largely expected near the lee
of the Cascades and deeper basin. Lastly this cooler pattern will
come with some moisture and the potential for patchy fog around
the northeast valleys during the overnight/early morning hours
Friday to Sunday: Toward Friday a weak ridge builds in before the
next trough starts to into the region heading into the weekend.
The overall threat of showers will retreat to the mountains zones
Friday and Saturday, then expand out more Sunday into next Sunday
night. Right now any precipitation during this time frame looks
light and the overall risk for wetting rain is less than 20
percent. Expect a mix of sun and clouds and overall cooler than
normal temperatures. Values recover a bit after Wednesday and
Thursday, but not by much. /Solveig
&&
.AVIATION...
00Z TAFS: Low pressure pushes through middle to high clouds and
isold to sct -shra near Cascades, SE WA and lower to central ID
Panhandle. Isold -tsra possible, including in the vcnty of
LWS/PUW, with smaller chances near OMK and EAT. A few showers
could skim by GEG/SFF/COE. Mainly VFR, except local MVFR with
haze/smoke over SE WA/lower ID through early afternoon.
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Moderate to high
confidence in VFR conditions. Low to moderate confidence in MVFR
conditions due to smoke/haze near PUW, LWS, GEG, SFF, COE, EAT;
Low confidence in -tsra at TAF sites.
-----------------------
Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance
For additional probabilistic information for NWS Spokane airports,
please refer to the Aviation Dashboard on our webpage:
https:/www.weather.gov/otx/avndashboard
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 60 87 57 81 53 68 / 10 0 0 0 10 50
Coeur d`Alene 59 85 56 81 53 70 / 20 0 0 0 20 70
Pullman 55 84 53 78 49 64 / 20 0 0 0 30 70
Lewiston 64 94 62 87 58 72 / 20 0 0 0 40 70
Colville 50 86 46 81 47 70 / 10 10 10 0 10 50
Sandpoint 55 83 52 78 49 67 / 10 0 0 0 20 70
Kellogg 62 83 59 79 55 64 / 20 0 0 0 30 80
Moses Lake 57 89 55 82 53 72 / 0 0 0 0 0 30
Wenatchee 65 87 61 81 58 71 / 0 0 0 0 10 30
Omak 61 90 56 83 54 76 / 0 0 0 0 10 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Red Flag Warning from noon to 7 PM PDT Monday for Eastern
Columbia Basin -Palouse -Spokane Area (Zone 708)-Lower
Palouse -Snake River (Zone 709).
&&
$$
Area Forecast Discussion
National Weather Service Pueblo CO
507 PM MDT Sun Sep 8 2024
.KEY MESSAGES...
- Isolated thunderstorms mainly mountains/valleys/I-25 corridor
this evening, ending by midnight.
- Little change Monday, with warm temperatures and isolated
afternoon showers and thunderstorms once again.
- At and above seasonal temperatures with daily afternoon showers
and storms, mainly over and near the higher terrain through the
middle of the week.
- Drier and breezy conditions leading to increasing fire danger
for the end of week into next weekend.
&&
.SHORT TERM /THROUGH MONDAY/...
Issued at 244 PM MDT Sun Sep 8 2024
Currently...Isolated thunderstorms across the area again today, with
most storms over/near the higher terrain as of 2 pm. Low levels look
slightly drier today than 24 hrs ago, while mid-levels have warmed a
touch with building upper ridge, suggesting storm strength and
coverage will be slightly reduced versus yesterday. Temps have crept
upward this afternoon, and most of the plains/I-25 corridor were in
the 80s to low 90s, with 70s/low 80s valleys and 60s/70s mountains.
For the remainder of the afternoon into this evening, expect
isolated to scattered storms to continue, mainly over the
mountains/valleys and I-25 corridor. Did spread low pops a little
farther east to encompass more of the plains for early evening,
given radar trends of some enhanced activity along the Palmer
Divide, while HRRR shows gust front and some weakening activity
making it eastward through Colorado City and Walsenburg toward
sunset. Wind/lightning and gusty winds will be the main storm
features into this evening, though like yesterday, a stronger cell
could produce some hail and a brief downpour. Convection then ends
by midnight, with clearing skies and seasonably cool min temps
expected.
On Monday, little change in the pattern with ridge overhead, and
just a subtle increase in heights/mid level temps and a small
decrease in surface moisture. Still enough recycled moisture from
Sunday`s storms for another round of afternoon convection over the
mountains, though lack of any significant forcing and slightly less
favorable thermodynamic profiles suggest rather weak/sparse activity.
Models again favor the ern San Juans for highest pops, isolated
coverage at best elsewhere, and more wind that rain with many
storms. Max temps likely to drift up a degf or two at many areas
given slightly warmer mid-levels, and some mid 90s look likely over
the lower Arkansas Valley.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
Issued at 244 PM MDT Sun Sep 8 2024
Modest west to southwest flow aloft continues across the region
through the day Wednesday, with upper level ridging across the
Rockies slowly sliding south ahead of an Eastern Pacific system
moving into the Pacific Northwest. Latest model data in good
agreement of increasing available moisture within the westerly flow
aloft will bring increasing coverage of afternoon showers and
thunderstorms to areas over the higher terrain both Tuesday and
Wednesday, with the albeit weak westerly flow, allowing for some
storms to push east across the high mountain valleys and immediate
adjacent plains. The proximity to the upper ridge will keep
temperatures at and above seasonal levels through the period,
with highs in the 80s to lower 90s expected across the Plains,
and mainly in 60s and 70s across the higher terrain, save 50s
at the peaks.
Beyond Wednesday, models are starting to come into better agreement,
especially ensemble mean data, which dig the Eastern Pacific system
into the Great Basin region on Thursday. These brings increasing
southwest flow across the Rockies, with latest model data indicating
much drier air embedded within the increasing southwest flow aloft.
The warm, breezy and dry conditions expected across the region
on Thursday will bring the potential for critical fire weather conditions
across the region, especially across portions of the southeast Plains,
where recent rainfall has been more spotty. Models continue to indicate
moderate to strong west to southwest flow aloft across the Rockies on
Friday, as the system lifts out across the Northern Rockies, with
moderating westerly flow in place on Saturday and Sunday behind the passing
system. This will keep the area mainly dry and warm through the period,
save for chances of orographic precipitation along and west of the
Continental Divide on Friday. Fire weather concerns remain on Friday,
especially across the plains, with only slightly cooler temperatures
in place for the weekend, behind the passing systems front.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 507 PM MDT Sun Sep 8 2024
VFR conditions expected at COS, PUB and ALS over the next 24
hours. Isolated -shra/-trsa over the higher terrain brings a
low risk of occurence at the terminals through 02Z, with PUB
seeing the best chances of breezy outflow winds this evening.
Clearing skies overnight with light diurnal wind regimes
expected through the rest of the taf period. Will see building
clouds again aft 18Z, with low probability of a vcsh/vcts aft 20Z.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...PETERSEN
LONG TERM...MW
AVIATION...MW