Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/02/23
Area Forecast Discussion
National Weather Service Binghamton NY
731 PM EDT Sun Oct 1 2023
.SYNOPSIS...
High pressure building over the area will bring dry and very warm
conditions through Thursday. The next frontal system moves through
Friday into Saturday, bringing periods of rain and a chance for
thunderstorms. It turns much cooler for the upcoming weekend, with
temperatures sliding back to well below average levels by Sunday.
&&
.NEAR TERM /THROUGH MONDAY/...
645 PM Update...
Minimal changes made at this time in this quiet weather pattern.
Blended in the latest obs over the next few hours. We`ll have to
keep an eye on the clouds to the north as they push south into
the area tonight to see if it may restrict some of the fog from
forming later on. See previous discussion below.
225 PM Update
High pressure remains in control through the near term period. A
building upper level ridge over the east-central Great Lakes region
will keep our area under a dry northerly flow aloft. Temperatures
will be well above average for early October, both during the day
and overnight periods.
This circulation around the upper level ridge may bring in some
scattered to broken clouds late tonight into Monday...and it could
also funnel some smoke/haze aloft over our eastern forecast zones.
Used the 12z HRRR smoke model to put in some haze for these areas;
mainly the Catskills down into Pike county in NE PA on Monday. With
the potential for some clouds moving in late tonight, it may put a
slight damper on fog formation; however still included fog in the
forecast due to uncertainty on extent and thickness of any cloud
cover. Lows tonight are mild, in the 50s and highs are well above
average on Monday, reaching the mid-70s to around 80 degrees.
Clear, calm conditions return Monday night with more valley fog
likely as a 1023mb surface high settles overhead. Similar overnight
low in the 50s expected across the region.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
220 PM Update...
Quiet conditions are expected for the middle part of the week as a
ridge of high pressure moves east across the region. A warmer
airmass will be present over the region as well, resulting in highs
near or even exceeding record temperatures (more details in climate
section). Highs Tuesday will be in the upper 70s to low 80s.
Wednesday will be a few degrees warmer with most in the 80s. The
highs were bumped up slightly above guidance. Nighttime temperatures
will fall into the 50s both nights though portions of the Finger
Lakes may stay in the 60s Wednesday night. Clear skies and light
winds will be favorable for fog developing Tuesday night and lasting
into Wednesday morning.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
220 PM Update...
High pressure will stick around through Thursday, though the warmer
air moves out as temperatures begin to trend cooler. An upper-level
trough will dig across the Midwest as it approaches the Northeast.
With it, a surface front approaches the region Thursday night,
bringing a slight chance for showers. Scattered showers ahead of
this front will be possible Friday with the front moving in later in
the day. Chances become more widespread overnight as the front
slowly moves through and a low develops north of the region. Models
continue to show some instability and shear Friday afternoon and
evening, enough to support a slight chance for thunderstorms.
Lingering showers will be possible Saturday with the front
eventually departing the region. Following the front, northwest to
westerly flow will advect cooler air and wraparound moisture into
the region, resulting in lake enhanced rain showers over CNY through
the rest of the weekend. There remains quite a bit of uncertainty
with the timing of this frontal system including the lake enhanced
showers that follow, so NBM guidance was used for PoPs with some
minor manual adjustments.
After getting one last taste of summer, fall will take over with a
significant cool down by the end of the weekend. Temperatures will
max out in the 70s Thursday, but will only climb into the 50s
Sunday. Overnight temps Thursday will be in the 50s and 60s. Upper
30s to mid 40s are then expected Saturday night.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
FEW-SCT high clouds will do little to prevent strong radiation
cooling. Crossover technique yields x-over temp around 57-58F
for most TAF sites, and have high confidence in IFR fog at ELM.
Moderate to high confidence in restrictions at ITH, but likely
more variable between MVFR and IFR. Low confidence at BGM though
valleys surrounding it will be fogged-in. AVP could see brief
MVFR in mist around dawn, but mainly VFR.
Northern sites are more challenging. Satellite imagery has shown
a plume of colder waters over Lake Ontario for >48 hours,
extending from offshore NW of Rochester to near Sodus Bay, then
along the shore to Oswego. This cold water plume appeared to
play a role in the development of widespread stratus downwind of
Lake Ontario this morning, impacting SYR and RME. The only
forecast model to properly initialize with cooler lake surface
temperatures has been the HRRR, and it appears to miss the
near-shore eastern edge of the plume. Despite that, it again
develops fog and low stratus over the SE end of the lake towards
dawn, impacting SYR and RME. These unusual factors are leading
to fairly low confidence, and while I`d prefer to wait for
satellite trends, this past morning`s restrictions developed
very quickly. So...introduced TEMPO IFR conditions for both RME
and SYR considering continuity from yesterday and the HRRR
signal.
After fog and/or low stratus burns off, VFR will prevail for
most of the day Monday area-wide, with light northerly winds
again.
Outlook...
Monday night through Thursday...Mainly VFR expected; high
confidence. Restrictions due to valley fog each morning most
likely at ELM (moderate to high confidence)
Friday...Restrictions possible as a system brings chances for
rain showers and a slight chance of thunderstorms.
&&
.CLIMATE...
High temperatures may be within a few degrees of record values
on Tuesday 10/3 with the potential for near or record highs on
Wednesday 10/4.
10/3 (Tue)
Avoca-84 in 1919: current forecast high is 82
Binghamton-81 in 1951: current forecast high is 79
Syracuse-86 in 1951: current forecast high is 82
10/4 (Wed)
Avoca-84 in 2007: current forecast high is 84
Binghamton-78 in 2017: current forecast high is 81
Syracuse-86 in 1951: current forecast high is 86
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.
&&
$$
SYNOPSIS...MJM
NEAR TERM...DK/MJM
SHORT TERM...BTL
LONG TERM...BTL
AVIATION...MJM/MPH
CLIMATE...BTL
Area Forecast Discussion
National Weather Service Cheyenne WY
539 PM MDT Sun Oct 1 2023
.SHORT TERM...(This evening through Monday night)
Issued at 330 PM MDT Sun Oct 1 2023
Forecast remains mostly on track for the short term period compared
to the previous shift`s forecast. However, this is pretty
drastically different from what models were showing this time
yesterday. Minimal impacts expected today with isolated
thunderstorms mainly in east central Wyoming later this evening. The
big story is Monday as this messy low ejects eastward. The trough is
forecast to slowly drift east-northeast overnight tonight before
speeding up as the center of the low moves over Wyoming. There are a
few main elements of this system to explore: the strong winds,
precipitation chances and subsequent potential for strong
thunderstorms, and temperatures associated with the cold front.
The strong pressure gradient develops along the Rockies as the
trough drifts east, and with a near 100kt jet aloft, strong winds
are expected across southeast Wyoming and western Nebraska beginning
Monday evening. Increased the winds in the wind-prone areas
behind the main cold front as the jet remains aloft, but winds
turn back westerly. With the 700 mb low moving farther north than
previously forecast, internal guidance is not showing quite as
high of high wind chances as yesterday, but they`re still present.
Subsidence is marginal at best, mainly staying confined to the
Laramie Range. CAG- CPR 850 mb gradients are in the upper 40s,
which is decent enough to produce 50+ MPH wind gusts. Best timing
estimate right now is Monday evening after 6 PM MDT. Opted not to
do a High Wind Watch at this time since confidence is just not
there yet.
Jumping to precipitation chances. There are pretty high chances of
precipitation as PWATs east of the Laramie Range are in the 90th
percentile, MUCAPE values 800-1000 J/kg, 30-50 knots of bulk shear,
and plenty of frontogenesis with the cold front passage. There is
still some uncertainty as far as timing of the cold front and if the
cold front is going to just push through quickly or stall out along
the WY/NE/SD border. SPC still has a Marginal Risk (Level 1 of 5)
across the High Plains east of Interstate-25. The primary threat
with these showers and thunderstorms will be strong outflow winds,
but isolated hail cannot be ruled out in the stronger updrafts.
Rainfall will mainly stay west of Interstate-25 through Monday
afternoon, then push eastward into the High Plains Monday evening.
HiRes guidance is still all over the place in terms of nailing
down timing. The HRRR is showing the front stalling, producing
much higher rainfall amounts over a longer period of time
initially Monday evening into Tuesday. However, the NAM Nest has
the initial thunderstorms staying tied to the front and pushing
east rather quickly between Monday afternoon, ending by late
Monday evening. Current forecast amounts are less than 0.10 inches
west of Interstate-25 and 0.20-0.30+ inches east of
Interstate-25. Locally higher amounts are likely though in
stronger isolated cells and in training storms.
Finally, temperatures! Ahead of the front we will see more of the
same temperatures we have been in the 70s and 80s. But, behind the
front, temperatures are set to drop into the 50s and 60s. While we
have been consistently in the 70s and 80s across southeast Wyoming
and the Nebraska panhandle, the 50s and 60s are actually the normal
high temperatures, or just below normal, for early October.
.LONG TERM...(Tuesday through Sunday)
Issued at 330 PM MDT Sun Oct 1 2023
The primary focus of this forecast package remains the system
passing through the area Tuesday into Wednesday which will bring
winds and showers to the area. After that, near freezing
temperatures are possible for much of the area.
Confidence is finally starting to increase with the early week storm
system. By Tuesday morning, the longwave trough will be moving
across the Rockies, with a potent shortwave rounding the base of the
trough and ejecting into the plains. The low to mid level cyclone
is expected to track across central Wyoming and into eastern
Montana and the Dakotas after. This is slightly further north
than previous model runs, but the local impacts of this shift are
fairly minor. The trailing front will push out of the area by
Tuesday morning, though some models have it stalling over our far
eastern counties until noon or so. Westerly flow will take over in
the wake of the front and advect in drier air underneath dry
southwest flow aloft. This will be part of the dry slot of the
classic extra-tropical cyclone. The surface component ejects off
into the northern plains very quickly, which should reduce
pressure gradients through the day Tuesday. Winds should decline
through the morning after peaking early.
The break in moisture will be fairly short lived. Another
shortwave will be right on the tail of the strongest wave Monday
night/Tuesday, moving towards the area from the northwest by
Tuesday afternoon. Expect mid to upper level moisture to increase
with the second wave combined with some element of wraparound flow
behind the first. This should increase cloud cover and shower
coverage again from the north and west, so also have higher PoPs
on that side of the CWA, with lower in the middle. Shower activity
picks up late Tuesday morning into the afternoon, mainly in areas
more favored by northwest flow which includes the higher terrain
and Carbon/Albany counties. Also increased PoPs on the north side
of the Cheyenne Ridge near Wheatland which can be favored for
shower activity in moist, unstable northwest flow due to the
convergence boundary that sets up in the lee of the northern
Laramie range. Dropped PoPs a bit outside of those areas, where
downslope winds may act to suppress precipitation. Snow levels
could be as low as 8500` during this period, but QPF has been
trending downward, even in the higher terrain. Sub-advisory
accumulations are likely on the higher peaks, and we may see
flakes flying as low as the I-80 summit (although the presence of
any precipitation at all there Tuesday during the day is more
uncertain).
The secondary shortwave dives a little further south towards central
Colorado on Wednesday. This is a slight chance from prior forecasts
too, with a slower exit of this feature. The GFS and ECMWF are now
showing the mid-level front stalling out east of the Rockies late
Tuesday night into Wednesday with modest isentropic lift overrunning
this. We may have light surface north-easterlies in place as the
surface high moves down the Rocky Mountain front range in the wake
of the departing trough. Most guidance suggests the precipitation
associated with this will be to our south, but definitely can`t rule
out stratiform precip Wednesday morning along the I-80 corridor and
points southward. Didn`t go in on this quite yet with the official
forecast, but this is something to keep an eye on.
Much quieter is expected for the remainder of the forecast period
after the system clears out Wednesday afternoon. The longwave trough
will move towards the Great Lakes region, while a strong ridge
builds in over the West Coast. This will leave northwest flow in
over the area. Once the cloud cover clears, we`ll have the potential
for freezing temperatures increasing for even the high plains.
Forecast lows now are generally in the mid 30s from the middle of
next week onward, but it wouldn`t take much to nudge this below
freezing. Aside from chilly mornings, Thursday looks like a nice day
with sunnier skies and temperatures beginning to warm. However, a
subtle shortwave riding the northwest flow will graze the area late
Thursday into early Friday. Most models are dry with this, but can`t
rule out some showers mainly in northern and eastern portions of the
CWA. This feature will also knock down temperatures slightly for
Friday but impacts will be short-lived. By next weekend, the ridge
axis will shift inland somewhat, giving us a buffer from the
northwest flow. Expect another period of well-above average
temperatures to return Saturday after a few chillier days.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 538 PM MDT Sun Oct 1 2023
Some scattered showers possible this evening around southeast
Wyoming terminals. Main concern with any showers will be gusty
winds. Showers dissipate later this evening. Conditions remain
breezy at western Nebraska terminals this evening with the low-level
jet still prevalent. Winds will ease late tonight. A few Hi-Res
models are showing northeast winds and low CIG moving into parts of
the Nebraska panhandle tonight. Currently, confidence is low in this
occurring. A cold front will push through the region on Monday.
Winds will pick up at all terminals during the day tomorrow with
gusts of 30 kts possible.
&&
.FIRE WEATHER...
Issued at 330 PM MDT Sun Oct 1 2023
Limited fire weather concerns due to increased precipitation
chances over the next week.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...LEG
LONG TERM...MN
AVIATION...SF
FIRE WEATHER...LEG
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
520 PM MDT Sun Oct 1 2023
...New AVIATION...
.SYNOPSIS...
Issued at 247 PM MDT Sun Oct 1 2023
The dryline will meander throughout the CWA today and tomorrow
giving mainly areas east of the Rio Grande a chance for
thunderstorms. Dry and warm weather is expected for Tuesday and
Wednesday. Finally, cooler air arrives for Thursday along with a
chance for rain.
&&
.DISCUSSION...
Issued at 247 PM MDT Sun Oct 1 2023
The CWA is wedged between a slow moving UL trough to the west and
a ridge to the east. This pattern has allowed a southerly tap of
moisture. The encroaching trough is trying to push dry air in from
the west, and a sharpening dryline has formed, running along the
Rio Grande as of 2pm. Thunderstorm chances will continue east of
the dryline but areas west of this line should be dry. With that
said, the dryline is expected to shift back west after dark, and
models are hinting at some convection moving northeast out of
Mexico possibly affecting Las Cruces and El Paso. Low POPs are in
the grids, but we`ll see who much this comes to fruition.
The trough will continue to slowly shift east on Monday while
moisture shifts back toward the AZ border by morning. Throughout
the afternoon, the dryline will once again sharpen and move east
with thunderstorms, potentially severe, possible east of it. How
far east will it make by evening? That`s a really good question.
Models are struggling with how far east to place the dryline with
the HRRR the farthest west, the Franklin-Organ-San Andres Line,
and the GFS completely clearing it from the CWA. The other
difficulty of tomorrow`s forecast is west of the dryline. The
upper-level trough axis will lag the dryline, but enough residual
moisture may be in place for thunderstorms to develop as suggested
by the HRRR as subtle height falls and DPVA arrive from the west.
Given high T-Td spread, strong winds would be the main concern
for storms west of the dry line.
The forecast becomes more certain again by Tuesday as the trough
sweeps out any lingering moisture while dropping temperatures a
few degrees behind a weak Pacific front. Wednesday will look
similar to Tuesday as we remain at the base of the trough. Each
afternoon will be breezy as well.
The forecast falls apart on Thursday. The UL trough shifts into
the Central US while a s/w passes along its back side. This s/w is
expected to push a decent side/back door cold front in from the
east and north, allowing our temperatures to drop below normal
through the remainder of the period. Parts of the Sacs could even
see their first freeze this weekend. This part of the forecast
looks fairly confident. The part of the forecast that falls apart
is whether a ridge will build over our area or an inverted
trough. The GFS keeps us dry, shunting appreciable moisture to our
south well into Mexico. The Euro places us beneath an inverted
trough, which allows rich moisture to move into the area. The NBM
appears to be favoring the Euro, even though GEFS members are
mostly dry. Looking at the various percentiles on 24 hour
rainfall, it seems there are two very clear scenarios at play: a
heavy rainfall event or we stay bone dry.
&&
.AVIATION...
(00Z TAFS)
Issued at 520 PM MDT Sun Oct 1 2023
Upper closed low to the west tonight, with strong southwest flow
ahead of it over the El Paso area. Skies SCT-BKN110 overnight,
with surface winds 180-220 at 05-10 knots. A few rain showers
possible before midnight, with minimal impacts to local terminals.
Winds increasing tomorrow afternoon, especially over W NM 190-240
at 10 to 20 knots. Gusts to 40 knots possible at KTCS tomorrow
evening. CB concentrated over E NM tomorrow, not expecting direct
impacts to KELP and surrounding terminals.
&&
.FIRE WEATHER...
Issued at 247 PM MDT Sun Oct 1 2023
Elevated fire conditions are expected, mainly west of the Rio
Grande for Monday. Winds will top out around 20 MPH, but min HR
values will be in the mid to upper teens. Farther east, richer
moisture will result in thunderstorm chances. The main uncertainty
for tomorrow is moisture quality west of the river as well as
thunderstorm chances as some models show isolated storms across
the Gila and areas near the divide while some forecast models keep
the CWFA clear of thunderstorms. Regardless, drier air should
continue to arrive for Tuesday with a reduction in storm chances,
but winds will be lighter alleviating any fire concerns.
Wednesday will be dry as well but moisture is slated to return for
Thursday.
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 70 92 65 89 / 20 20 20 0
Sierra Blanca 61 83 59 83 / 30 50 40 10
Las Cruces 64 87 55 84 / 20 20 10 0
Alamogordo 64 85 56 82 / 20 30 20 0
Cloudcroft 46 62 42 59 / 30 50 40 0
Truth or Consequences 62 84 52 82 / 10 20 10 0
Silver City 54 77 47 74 / 10 10 10 0
Deming 60 87 51 84 / 10 20 10 0
Lordsburg 58 85 49 81 / 10 10 0 0
West El Paso Metro 69 91 63 86 / 20 20 20 0
Dell City 63 86 60 86 / 30 50 40 10
Fort Hancock 65 91 63 90 / 30 50 30 0
Loma Linda 62 82 58 79 / 20 30 20 0
Fabens 66 91 62 87 / 20 20 20 0
Santa Teresa 64 88 57 84 / 20 20 10 0
White Sands HQ 66 89 60 84 / 20 30 20 0
Jornada Range 64 87 55 82 / 20 30 10 0
Hatch 62 88 52 84 / 20 20 10 0
Columbus 63 88 55 85 / 10 10 0 0
Orogrande 62 85 57 82 / 20 30 20 0
Mayhill 50 72 48 71 / 30 60 40 0
Mescalero 50 73 46 70 / 30 50 40 0
Timberon 48 70 44 69 / 30 70 40 0
Winston 51 75 41 74 / 10 20 10 0
Hillsboro 56 82 48 81 / 10 20 10 0
Spaceport 61 84 51 82 / 20 30 10 0
Lake Roberts 48 75 40 72 / 10 20 10 0
Hurley 55 82 47 79 / 10 10 10 0
Cliff 51 83 42 81 / 10 10 10 0
Mule Creek 52 77 45 74 / 10 10 0 0
Faywood 57 81 50 78 / 10 20 10 0
Animas 58 85 48 84 / 10 10 0 0
Hachita 57 86 50 84 / 10 10 0 0
Antelope Wells 57 85 50 85 / 0 10 0 0
Cloverdale 56 80 50 80 / 10 10 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
TX...None.
NM...None.
&&
$$
FORECASTER...30-Dennhardt
Area Forecast Discussion
National Weather Service Goodland KS
606 PM MDT Sun Oct 1 2023
.UPDATE...
Issued at 604 PM MDT Sun Oct 1 2023
Based on the latest area obs and satellite data, have allowed the
Blowing Dust Advisory to expire. Only a few obs were showing
around 5sm before cancellation, despite winds still gusting 35-45
mph in spots.
&&
.SHORT TERM...(This evening through Tuesday Night)
Issued at 310 PM MDT Sun Oct 1 2023
At the start of the short term period, the latest RAP analysis
displays an upper air cutoff low over NV allowing for a south-
southwesterly flow over the CWA being between the low and an upper
air ridge over the Great Lakes region. Current surface observations
and radar imagery report windy conditions with some areas of lower
visibilities due to blowing dust as a result while the far eastern
portions have some isolated showers occurring. Going forward through
the rest of today, models project the low moving eastward over the
NV/UT border allowing for the flow over the CWA to turn more
southwesterly overnight. At the surface, models show a surface low
over southeastern WY/northern CO in the evening allowing for a tight
pressure gradient across the CWA (around an 8 mb change from west to
east). Looking at forecast model soundings, the CWA sees southerly
winds gusting up to and even a little above 40 kts going into the
evening. With these winds, blowing dust is possible for the
remainder of the afternoon into the early evening hours for most of
the CWA which could reduce visibilities (thus the ongoing Blowing
Dust Advisory until 00Z). Opted to add in some slight chance PoPs in
the far eastern portions of the CWA as well due to the ongoing
isolated showers and storms and the possibility of some storms
moving into the region from the DDC CWA. Severe weather is not
expected with storms today as the non-convective winds appear to be
the main story across the region. While minimum RH values are not
supportive of fire weather for the rest of today, these winds along
with dry fuels continue to make it a dangerous environment should a
wildfire start. Overnight lows for tonight range between the middle
50s and middle 60s.
For Monday, forecast guidance shows the western low moving over UT
during the day and opening up into a trough by the evening hours.
This setup allows for the CWA to return to a south-southwesterly
flow aloft during the evening during which a shortwave disturbance
is seen passing through the CWA`s upper air flow. At the surface,
models show another surface low moving across northern CO in the
afternoon and into western NE by the evening. This will not only
allow for the windy southerly flow to continue across the CWA
(albeit slightly slower than Sunday`s flow), but also bring back
chances for showers and thunderstorms starting in the late afternoon
hours. Precipitation chances look to begin in the southwestern
portions in the late afternoon with coverage drifting over to the
rest of the CWA going into the evening. When looking at the latest
model forecast convective parameters, SBCAPE values look to be
between 1500-2000 J/kg with higher values in the CO counties.
Surface to 500mb bulk shear values look to be at their highest
though below 40 kts in the evening particularly south of I-70. SPC
currently has a marginal risk due to the potential for strong winds
and large hail for areas along and east of a meridian passing
through Oakley, KS. With windy conditions expected, continuing to
message the dangerous fire weather conditions. Also, added in some
patchy blowing dust during the afternoon for areas that seemed the
most favorable according to local blowing dust research parameters.
Daytime highs for Monday are forecast to be in the upper 70s to
lower 90s while overnight lows expect to range between the upper 40s
and lower 60s.
On Tuesday, model guidance forecasts the trough moving eastward over
the Rockies keeping the CWA to the east of the trough axis and
underneath the front portion of the trough. Another shortwave
disturbance looks to pass through the flow over the CWA during the
late afternoon/evening hours. At the surface, a cold front looks to
pass through the CWA during the day allowing for shower and
thunderstorm chances throughout the day. Forecast convective
parameters look to support the marginal to slight risk for severe
weather in the eastern portions of the CWA with bulk shear values
reaching around 50 kts and SBCAPE values over 2000 J/kg. Will
monitor this severe weather potential going forward, but ingredients
look to be there with a good amount of moisture coming in from the
850mb. Also, there looks to be a possible heavy rainfall threat with
PWAT values over one inch and the WPC placing a marginal risk for
excessive rainfall in eastern portions of the CWA. Flash flooding
might not be an issue due to how dry it has been lately, but will
monitor in case conditions change. Tuesday`s daytime highs look to
be cooler due to the cold front passage being in the lower 70s to
lower 80s followed by overnight lows in the lower 40s to lower
50s.
.LONG TERM...(Wednesday through Sunday)
Issued at 130 PM MDT Sun Oct 1 2023
Relatively quiet weather is expected after Tuesday storm system
clears the area with any lingering precipitation chances rapidly
diminishing through the early morning hours. While medium range
models disagree with some of the larger details surrounding whether
or not short wave trough gets cutoff across the southwest CONUS.
While there are differences, model consensus provides high
confidence that CWA will remain in strong northwesterly flow aloft
bringing the potential for much cooler air masses to build into the
region. Much more seasonal conditions are anticipated throughout
the week with potential for the first frost of the year increasing
with each frontal passage. Chances look highest on Friday night and
Saturday morning as strong sfc high will settle over the area
bringing light winds, clear skies and dry air, resulting in optimal
cooling conditions. Those with sensitive outdoor vegetation or want
to prolong the growing season a bit longer should be ready to take
appropriate measures by the start of the weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 439 PM MDT Sun Oct 1 2023
VFR conditions expected for both terminals through the forecast
period. Winds for KGLD, south 15-25kts w/ gusts to 40kts at times.
Winds for KMCK, south 15-25kts w/ gusts to 35kts at times. LLWS
05z-20z Monday around 190@40kts.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...076
LONG TERM...JRM
AVIATION...JN
Area Forecast Discussion
National Weather Service Marquette MI
807 PM EDT Sun Oct 1 2023
.SHORT TERM...(Through Tonight)
Issued at 320 PM EDT SUN OCT 1 2023
Water vapor imagery and RAP analysis show an amplified mid-upper
level trough over the western U.S. with ridging downstream across
the Mississippi Valley and Great Lakes region. At the north end of
the ridge, WAA along the 850 mb warm frontal boundary and at the
nose of the 850 mb theta-e ridge has been sustaining convection
through much of the day across central and eastern portions of the
U.P. The latest radar scans shows a line of storms from just north
of Granite Island through Munising to Port Inland. Some of these
storms have been producing brief, torrential rainfall with radar
estimates of 2-3in/hr rainfall rates at some locations. There was a
Facebook report of 4 inches of rainfall in Daggett last night/early
this morning. Otherwise away from the convection, sunny skies across
much of the west and south central interior have allowed temps to
soar into the upper 70s to mid 80s, well above normal for early
October.
Tonight, CAMs have the convection over the eastern counties slowly
moving east and weakening over the next several hours as the 850 mb
warm front moves north and east of the area. Expect clear or
clearing skies tonight across the area although there is a slight
chance that another round of convection could fire tonight over
central and eastern Lake Superior as another shortwave rounds the
500 mb ridge. Otherwise, expect even milder overnight lows (in spite
of clearing skies) courtesy of the anomalously warmer airmass over
the region. Most spots should bottom out in the upper 50s to lower
60s, but downsloping areas closer to Superior in the western UP may
stay as warm as the mid and even upper 60s. Patchy fog can`t be
ruled out east half tonight given low-level moisture from the recent
rainfall in an upslope southerly flow.
.LONG TERM...(Monday through Sunday)
Issued at 308 PM EDT SUN OCT 1 2023
Upper air pattern consists of a 500 mb closed low and trough in the
western U.S. and a ridge across the eastern half of the U.S. 12z
Mon. Dry forecast setting up for Mon along with warm southwest
winds. Above normal temperatures look to continue into Wed.
In the extended, the GFS and ECMWF show a deep and broad 500 mb
trough across the central U.S. with ridging on both coasts 12z Thu.
Troughing digs into the Great Lakes region 12z Fri and moves into
the lower Great Lakes 12z Sat. Ridging moves into the Rockies 12z
Sun. Temperatures look to start off above normal Thu and then fall
to below normal Fri through Sun. With troughing in the area, looks
pretty showery for this forecast.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 807 PM EDT SUN OCT 1 2023
VFR is expected to be the predominant flight category for the TAF
period. However, LLWS will be a threat at all TAF sites tonight
with the arrival of a strengthening LLJ to the west. At the
surface, winds will generally be southerly at 5 to 10 kts.
And, gusts up to 21 kts are possible at CMX tonight.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 308 PM EDT SUN OCT 1 2023
Winds should remain less than 20 kt through tonight, primarily out
of the northeast in western Lake Superior and out of the southeast
in the eastern half of the lake and will switch to the southwest
tonight. Expect patchy fog to linger over the lake through tonight
with showers and thunderstorms moving north across the east half of
Lake Superior as well. South to southwest winds will increase
through Wednesday, with winds gusting 20-30 kt at times. A few gale
force gusts are possible Wed afternoon across the west A cold front
will turn winds westerly Wednesday night, with 20-25 kt gusts
possible through the end of the week.
&&
.CLIMATE...
Issued at 308 PM EDT SUN OCT 1 2023
Record high temperatures at the NWS Office in Negaunee:
Oct. 1: 83 (1976)
Oct. 2: 87 (1992)
Oct. 3: 78 (2005)
Oct. 4: 76 (2007/2011)
Record warm low temperatures at the NWS Office in Negaunee:
Oct. 1: 57 (2000)
Oct. 2: 60 (2005)
Oct. 3: 65 (2005)
Oct. 4: 60 (2005)
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Dense Fog Advisory until 8 AM EDT /7 AM CDT/ Monday for LSZ162.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...07
AVIATION...TDUD
MARINE...07
CLIMATE...07
Area Forecast Discussion
National Weather Service New York NY
1010 PM EDT Sun Oct 1 2023
.SYNOPSIS...
High pressure will build in through mid week. The high will
then give way to a frontal system at the end of the week.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
The forecast remains on track through the overnight. High
pressure continues to build into the region with mostly clear
skies and light winds. Some patchy fog may develop for the
interior, especially early Monday morning. There may be some
haze, especially across eastern Long Island and southeast CT.
Lows tonight will fall into the 50s, except lower 60s in and
around the NYC metro area.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Ridging at the surface and aloft continue through the short
term period with rising heights. It will remain dry and cloud
free. Expect temperatures on Monday to climb into the middle and
upper 70s. A northerly flow however is expected to usher in
additional smoke/haze from the Canadian wildfires. The latest
HRRR smoke fields showing most if not all of the forecast area
seeing some smoke aloft. So will include haze once again in the
forecast for the the entire region on Monday.
Monday night lows will fall into 50s with the NYC metro
remaining in the lower 60s. It will remain mostly clear with
relatively light winds, so some patchy fog can not be ruled out.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Deep layered ridging over the Northeast will promote an
extended period of dry weather through the mid week period. It
will remain dry through Thursday with above normal temperatures.
A 500 mb trough then digs into the Great Lakes Region on
Friday. This will help push a cold front through the forecast
area at some point Friday night into Saturday. The global models
over the last 24h continue the trend to a more amplified
system, with the upper trough taking on a negative tilt. It`s
still too early to be too specific with the timing, but there
remains a chance of showers across the area starting late
Thursday night as moisture filters in from the Atlantic. Highest
overall chances appear to be Friday night and Saturday as the
frontal system moves into the area. Highs both days will be
cooler and closer to normal. The system should be off to the
east on Sunday, but the upper trough remains over the region
with a cyclonic flow aloft. Breezy and noticeably cooler as high
pressure attempts to build in from the northwest.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Mainly VFR through the middle of the week as high pressure
builds over the northeast.
N flow will continue to diminish tonight before slowly
increasing after day break Monday morning. Winds likely veer to
the NNE or NE through the rest of the morning. Wind speeds
should then remain 10 kt or less. There is a chance for a late
afternoon or early evening sea breeze along the coast, mainly
for KJFK and KISP, but wind speeds likely end up light.
Some smoke/haze from Canadian wildfires may keep KGON
visibility around 5SM tonight. Haze aloft is possible late Monday
morning and afternoon with potential for visibility to lower to
around 6SM.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No visibility restrictions are possible Monday with any haze
staying aloft.
OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
Monday Night Through Thursday...VFR.
Friday...Mainly VFR. Chance of late day showers with MVFR.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
SCA conditions expected to remain for the ocean waters as a
lingering E swell maintains wave heights 4-6 ft through Monday.
Sub SCA conditions are then forecast Monday night through the
middle of the week with a weak pressure gradient in place. Winds
and seas then increase Friday into the Friday night with the
approach of a cold front. There is a chance that seas on the
ocean build to 5 ft by the end of Friday night.
&&
.HYDROLOGY...
No hydrologic impacts are expected.
&&
.TIDES/COASTAL FLOODING...
Minor coastal flooding is not anticipated with tonight`s high
tide cycle. A statement has now been issued for the late morning
to early afternoon high tide cycle for the south shore back
bays of Nassau and Queens, as well as Southern Fairfield and
Southern Westchester Counties. Coverage of minor flooding may be
just enough to eventually warrant an upgrade to an advisory for
these zones. Will wait for updated guidance and monitor gauge
observation trends for more confidence before issuing any
changes to headlines.
NOTE: The Peconic River at Riverhead NY tidal gauge is out of
service for unrepresentative data (water levels about 3 ft too
high). The gauge is being looked into by our partners at the
USGS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Monday for ANZ350-353-355.
&&
$$
SYNOPSIS...BC/JC
NEAR TERM...BC/DS
SHORT TERM...BC
LONG TERM...JC
AVIATION...DS
MARINE...BC/JC
HYDROLOGY...BC/JC
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Pocatello ID
104 PM MDT Sun Oct 1 2023
.SHORT TERM...Tonight through Monday Night.
A broad area of low pressure is centered over Nevada this afternoon.
Several smaller circulations are rotating around the larger low
pressure area. One such area is spinning through East Idaho this
afternoon and has been responsible for the widespread showers this
morning across the Magic Valle and lower Snake Plain. Scattered
showers and thunderstorms have developed in the afternoon heating as
some clearing worked into South Idaho. Models show most if not all
of the activity diminishing this evening. With plenty of low level
moisture around and light winds expected tonight, models are hinting
at the development of low stratus and fog particularly over the
Magic Valley and then spreading up the Snake River. At this time,
not expecting significant widespread impacts, but there`s a slight
chance of some areas of locally dense fog for the Monday morning
commute.
On Monday, the low will spin into Utah. A band of showers and
isolated thunderstorms is expected to develop across the eastern
highlands during the morning and persist through the afternoon.
Meanwhile, isolated to scattered showers will develop across the
central mountains on the back side of the low. Rainfall amounts
tomorrow look heaviest across the eastern highlands where up to 0.25
inches is most likely and some heavier cells could produce rainfall
amounts closer to 0.50 inches. In the higher terrain and on
ridgetops, up to 0.75 inches is likely. Snow levels into Monday
continue to look high, generally above 8500 feet. High temperatures
on Monday are expected to be about 15 degrees below normal from the
combination of showers, cloud cover and cooler air advecting into
the region.
Monday night, the low will lift into Wyoming and showers on the back
side of the low will move through East Idaho from the northwest.
Additional rainfall amounts look light, generally around 0.10
inches and snow levels will remain around 8500 feet. Temperatures
Monday Night are expected to remain above frost thresholds across
the Snake Plain and Magic Valley as we will maintain a bit of a
breeze through the night and cloud cover will help insulate us as
well.
13
.LONG TERM...Tuesday through Next Sunday.
Another shortwave will work through the region, bringing one last
push of precipitation associated with this system. The bulk of
precipitation will be concentrated over the eastern mountains as the
low shifts further east on Tuesday. Between Tuesday and Wednesday
mornings, a Trace to third of an inch will accumulate across the
eastern half of the CWA, while the National Blend 75th and 90th
Percentiles suggest around one tenth to half an inch as the more
extreme scenario. As the upper trough slowly departs to the
northeast, high pressure off the west coast will build further
inland beginning Wednesday through the weekend. Under clear skies,
overnight temperatures will likely drop low enough to support frost
formation across the Snake Plain Wednesday and Thursday mornings.
Daily highs will warm by several degrees each day and will finally
run just above normal by next weekend. Cropp
&&
.AVIATION...Scattered showers and a few thunderstorms have developed
in afternoon heating. Best chances for storms are around IDA and PIH
where clear slot on satellite is punching into those areas. However,
other TAF locations stand a chance at seeing the storms although
confidence is less because cloud cover remained over those areas
into the early afternoon. Inside the showers IFR conditions exist as
evidence from obs this morning, although TAFs are a bit more
optimistic and assume mainly vicinity convection. NBM supports wind
gusts to 20kts at PIH and IDA, however with the cloud cover we are
having trouble mixing to realize those gusts. Other concern is for
the potential development of low stratus late tonight and early
Monday morning. The HRRR shows development of IFR fog/stratus across
the Magic Valley and along the Snake River which could impact PIH
and IDA as well. The NBM offers only a 20 to 30 percent chance of
IFR ceilings developing, but is showing a MVFR to low VFR deck
developing in its place. Given the low confidence hinted at
development of low stratus in the TAFs. If stratus develops in the
Magic Valley, there is potential for it to lift into SUN Monday
afternoon when the winds switch to upvalley. So, have mentioned few
to sct low clouds for now. Once again, confidence of low ceilings
advecting into SUN at this point is low.
13
&&
.FIRE WEATHER...The low to our south will continue to lift northward
over the next couple of days, bringing multiple rounds of precipitation
through early week. Showery precipitation and isolated storms will
continue through early this evening with a break until early tomorrow
morning. The next push will work through the eastern highlands and
central mountains beginning early tomorrow and continue through
early Tuesday when the next wave arrives. During these 48 hours,
the most rain will be observed across Fire Weather Zones 411 and
413. Another quarter inch, give or take, will accumulate across
the central mountains and portions of the Snake Plain, with half
an inch to one inch in the eastern mountains. As the upper trough
slowly departs to the northeast, high pressure off the west coast
will build further inland beginning Wednesday through the weekend.
Under clear skies, overnight temperatures will likely drop low
enough to support frost formation across the Snake Plain Wednesday
and Thursday mornings. Daily highs will warm by several degrees
each day and will finally run just above normal by next weekend.
Cropp
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Pueblo CO
930 PM MDT Sun Oct 1 2023
.UPDATE...
Issued at 925 PM MDT Sun Oct 1 2023
Overnight forecast looks in good shape, with best chance of
convection through about 12z over srn sections as activity rotates
northward out of NM. Did make some adjustments to early morning
Monday forecast, as HRRR and to a lesser extent the 00z NAM
suggest convection may persist and even expand somewhat between
12z and 18z. Added some pops for at least isolated storms to most
eastern mountains and valleys for Mon morning for now, though if
HRRR is correct, even I-25 corridor could see at least some
brief/windy convection in the morning before main show later in
the day.
&&
.SHORT TERM...(This evening through Monday)
Issued at 243 PM MDT Sun Oct 1 2023
Key Messages:
1) Southerly and southwesterly winds increase for today and tomorrow
2) Chances for showers and thunderstorms increase tomorrow, some of
which could be severe.
Currently..
Water vapor imagery depicts high amplitude troughing over the
Rockies, with a cutoff low moving into the Great Basin. Shortwave
energy traversing through the trough has sparked showers and storms
to our west and to our south, though most of our forecast area is
dry today. Earlier light showers over Chaffee and Fremont counties
have mostly dissipated. Winds are gusting around 35 to 40 mph
across much of the area, with highest gusts coming in around 50
mph in both Las Animas County and the top of the Wet Mountains
as of 2pm. Dewpoints are in the 30s and 40s across much of the
area, though Springfield`s dewpoint is, notably, at 58 as of 2pm.
Rest of Today and Tonight..
Expecting showers and thunderstorms to remain mostly to our south
and southeast for the rest of today and tonight, with some storms
possibly making their way in to southern Las Animas, Baca, and
Prowers counties. Wind gusts will be the main concern for the rest
of today, with synoptically driven wind gusts up to 45 mph possible
across much of the area. Thunderstorm wind gusts could be damaging
with stronger storms, where gusts up to 70 mph are possible this
afternoon and this evening, especially across Las Animas, Baca, and
Prowers counties. Overnight lows look to remain about 5 to 10
degrees above normal as winds keep mixing in place through much of
the overnight hours.
Tomorrow..
Models are in agreement with tomorrow`s progression of the trough,
bringing the associated low across the Utah and Wyoming border by
tomorrow afternoon. Embedded shortwave energy and the increase in
synoptic forcing should allow for an increase in both coverage and
intensity of storms for Monday afternoon and Monday evening across
much of the forecast area. Showers and thunderstorms look to spark
as early as 11am over the San Juans, spreading north-northeast and
into the Sangres and southern I-25 corridor by early afternoon. By
3pm, looking at widespread chances for showers and thunderstorms
across area, some of which could become severe. Forecast sounding
profiles indicate a modest amount dryness in the low-levels,
especially across the I-25 corridor. This would hint at more of a
wind chance for our mountain adjacent plains, with higher hail
chances further south and east where better moisture and instability
could be realized. Overall, looking like a very active day with main
risks being wind gusts to 70 mph and hail up to 2 inches possible,
especially further south and east.
.LONG TERM...(Monday night through Sunday)
Issued at 243 PM MDT Sun Oct 1 2023
Key messages:
- Strong to severe thunderstorms southeast plains Monday night
- Turning cooler with light snow accumulations for the higher
mountains through Wed Morning and a first hard freeze for the San
Luis Valley Wed Night.
The upper trough swings through southern CO Monday night/Tuesday
morning with the strongest forcing moving through the plains during
the overnight hours. Until this trough axis moves through, the
southeast plains will see rounds of thunderstorms spread up from the
south. There will be the possibility of strong to severe storms
into the late evening and perhaps overnight hours across the
plains as southerly winds keep a fetch of 50+ to near 60 degree
dew points streaming northward into the region ahead of the upper
trough. CAPEs are greatest during the early evening, but as the
upper trough approaches, some cooling aloft may keep enough CAPE
for strong to severe thunderstorms even past midnight. Strong
unidirectional flow results in straight line hodographs with the
potential for splitting supercells. Large hail (up to 2 inches)
and damaging winds (up to 70 mph) will be the primary risk with
these fast moving storms through the evening, with a trend towards
damaging gusts and smaller hail overnight as 75% of HREF members
show CAPE values dropping under 1000 J/kg after 03z. Otherwise,
higher peaks will pick up a few inches of snow Monday night before
a dry slot moves in for Tuesday.
Tuesday could see some brief critical to near critical fire weather
conditions along portions of the I-25 corridor and lower eastern
slopes of the southeast mountains as strong westerly winds behind
the first trough axis mixes down into the lee side surface low
during the morning. Dew points drop in the afternoon and the
southward advancing cold front is now a tad slower in latest model
runs, reaching the Arkansas River around 00z in the NAM12 runs while
EC and GFS drop it to near the southern CO border by the same time.
For now, not getting sufficient coverage or duration of low humidity
values for Red Flag criteria, but it could be close depending on the
timing of the front. With low confidence, will hold off on any fire
weather watches though this period will need to be monitored
closely should runs maintain a slower trend and further dry
surface dew points.
More energy dropping southeastward from the Pacific NW keeps
troughing out west which moves across southern CO Tuesday
night/Wednesday. This sends a reinforcing cold front through the
area late Tuesday night into Wednesday morning with a brief round
snow across the central and southeast mountains as H7 winds shift
out of the east and northeast. Moisture may be the lacking
ingredient with models showing some light qpf and snow possible
mainly for the Pikes Peak region during this period. Snow levels
drop to near 9000 feet Tuesday night before rising slowly Tuesday
afternoon back to near 10kft. A couple inches of snow will be
possible across Pikes Peak with most areas along the east slopes
of the mountains starting out cool and cloudy Wednesday morning.
Temperatures may struggle to warm into the 60s across the Pikes
Peak region while the remainder of the southeast plains and
valleys warm into the 60s to lower 70s under clear skies.
Any lingering showers will diminish Wednesday evening. Clear
skies and dry conditions will bring a good chance for a hard
freeze to the San Luis Valley Wednesday night with up 70 percent
of the NBM members having low temperatures 28 degrees or below
across southern and central portions of the San Luis Valley. Even
Tuesday night could see some brief freezing temperatures depending
on cloud cover with 80% of ensemble members showing below 32
degrees. Will be monitoring these time frames for frost freeze
headlines as early as Tuesday night as details become more
certain.
Another dry period sets in with a gradual warm up into next weekend
as high pressure out west transitions over the Rockies. -KT
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 243 PM MDT Sun Oct 1 2023
VFR conditions are expected at all three TAF sites, KCOS, KPUB, and
KALS, for the next 24 hours. Southwesterly winds are expected to
continue gusting up to 35kt at KCOS and KPUB through the rest of
this afternoon and into this evening, with gusts up to 45kt for KALS
this evening as well. Winds weaken slightly overnight, but are
expected to gust over 35kt at all three TAF sites for tomorrow as
well. There is a slight chance that blowing dust could restrict
visibility at times later this afternoon, especially at KALS, but
confidence is too low for a mention in the TAF at this time. Chances
for showers and thunderstorms increase tomorrow after 18Z.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...PETERSEN
SHORT TERM...EHR
LONG TERM...KT
AVIATION...EHR