Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/23/25
AREA FORECAST DISCUSSION
National Weather Service Albany NY
954 PM EST Sat Feb 22 2025
.SYNOPSIS...
Clouds will increase ahead of an upper level disturbance
tonight with some scattered snow showers mainly north and west of
the Capital Region. The snow showers will continue on Sunday
especially over the southwest Adirondacks but mainly dry conditions
and near seasonable temperatures for the rest of the region to close
the weekend. Above normal temperatures open the week with a slight
or low chance of rain or snow showers northwest of Albany.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
.UPDATE...As of 0953 PM EST...Once again few changes were
needed with this forecast update outside of minor adjustments to
tempertures and PoPs. Light snow showers are beginning to sink
south and east into the Southwest Adirondacks as the
aforementioned shortwave is shifting through the eastern Great
Lakes and cool westerly flow is kicking moisture off the Lakes.
Light accumulations are still anticipated through tomorrow
morning in the Southwest Adirondacks, Southern Greens, and
Berkshires with flurries possible in the Upper Hudson and Mohawk
Valleys. See the previous discussion below for additional
details.
.PREVIOUS DISCUSSION...
As of 346 PM EST...High pressure continues to move east of the
VA/NC Coast this afternoon. Flat mid and upper level ridging is
moving downstream of NY and New England, as a weak warm front
moves through. Some mid and high clouds will quickly move
towards the region from the south and west ahead of the next
short-wave located over the Great Lakes Region late this
afternoon.
Weak warm advection with the short-wave and warm front will
cause some light snow showers to develop over and near the
western Adirondacks, southern Greens and perhaps the Lake George
Region tonight. The cold front to the system will approach from
the west for the overnight period with additional snow showers
tapping lake moisture. The low-level moisture profiles on the
models soundings on the 3-km HRRR and NAMnest look dry for
hardly any pcpn south of I-90. The favored flow off Lake
Ontario and the westerly upslope flow off the southern Greens
may allow for a half inch to inch of snow in a few spots with
perhaps isolated 2" amounts over the high peaks. Temps will not
be as cold as last night with lows in the teens to lower 20s.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
Key Message:
- Max temps moderate to above normal readings to open the week.
Discussion:
Tomorrow...The winds shift to the west to northwest with the passage
of the cold front through the day, but the boundary stalls near
or over the region. The push of cold advection is not very
strong. Some residual lake effect and westerly upslope snow
showers may persist into the afternoon with additional light
snow accums. The effects of downsloping and a trend to partly
sunny conditions south and east of the Capital District and I-90
should allow for max temps close to the NBM in the lower to mid
30s in the major valleys with a few upper 30s in the mid Hudson
Valley, and 20s to around 30F over the hills and mtns.
Weak high pressure /~1020 hPa/ builds in over the forecast area
Sunday night with the lake effect snow showers and flurries
ending. The skies may go partly cloudy to mostly clear with some
decent radiational cooling. We favored the colder MAV/GFS MOS
guidance for some colder readings north and west of the Capital
District with lows in the single digits with lower to upper
teens from the Capital District south and east.
The weak mid and upper level ridging flattens over the forecast
area on Monday, as the boundary lifts north of the region as a
warm front. The next short-wave trough amplifies and digs
equatorward from central Ontario. Most of the day should be dry
with the mid level flow becoming zonal and then southwest
aloft. Clouds begin to increase within the low to mid level warm
advection pattern. South to southeast winds increase to 10 to
15 mph. The best chance for a rain or snow shower will be over
the southern Dacks. Max temps rise about 5 degrees above normal
with 40-45F readings in the valleys and mid and upper 30s over
the higher terrain (a few colder pockets at the high peaks). The
best chance of a rain or snow showers within the warm sector
will be from the Mohawk Valley, Capital Region and Berkshires
north and west Monday night with the next upper level
disturbance and short-wave. Min temps will be in the upper 20s
to lower/mid 30s.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
Key Message:
- Above normal temperatures will continue for much of next week
with a series of clipper systems bringing periods of rain and
snow showers at times. QPF remains light with the systems.
Discussion:
The first in a series of short-wave troughs brings some scattered
rain and snow showers to the region on Tue. There are some slight
timing differences with the ensembles, medium range deterministic
guidance and NBM. Most favor a warmer solution with light rain
showers for most of the region with increasing clouds during the day
with a rain/snow mix over the higher terrain. The clipper low and
short-wave move northeast of the region Tue night with any scattered
snow showers and flurries ending over the southern Greens and
western Dacks. Snow amounts will generally be a coating to less than
two inches in these areas. Max temps rise above normal Tue in the
lower to mid 40s in the valleys with some readings in the upper 40s
in the mid Hudson Valley and 30s to around 40F over the mtns. Lows
fall back mid 20s to lower 30s.
Flat mid and upper level ridging builds in briefly for the mid week.
A sfc anticyclone settles over the region ahead of the next short-
wave trough upstream. Some sunshine and above normal temps by 5 or
so degrees are expected Wed with upper 30s to mid 40s below 1000 ft
in elevation and 30s above it. Clouds increase Wed night from the
west/southwest ahead of the next clipper low/occluded front a 20-40%
chance of snow showers based on the NBM. The higher probabilities
are north of I-90. Lows due to wet bulb cooling fall back into the
mid 20s to lower 30s. Some warm advection occurs ahead of the
clipper and a frontal passage for a chance of rain or rain/snow
shower mix with QPF amounts mainly a tenth to quarter of an inch.
Highs continue above normal in the 30s to lower/mid 40s. Cold
advection occurs in the wake of the wave and front. In the cyclonic
flow in the wake of the short-wave some scattered/isolated flurries
may persist Thu night with lows in the 20s with some teens over the
Adirondack Park and southern Greens.
Friday into next weekend...A brief lull in the northern stream
activity occurs on Friday with a slight chance of rain/snow
showers/flurries possible north and west of the Capital Region. The
next disturbance/clipper arrives potentially on Saturday with low
chances of rain and snow showers. Temps finish the week and open
the weekend at or above climatological normals for late Feb.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
Through 00z Monday...VFR conditions prevail across all terminals
this evening as clouds increase across the region ahead of an
incoming disturbance. VFR conditions should persist through the
00z forecast cycle with ceilings progged to remain well within
this threshold. It is possible that KPSF see some light snow
showers in its vicinity early tomorrow morning which could
worsen conditions to MVFR or even IFR, but confidence was not
high in this element of the forecast, so left this out of the
TAF for now. Winds will primarily prevail out of the southwest
to start, gradually veering to the northwest by the end of the
period with sustained speeds remaining under 10 kt.
Outlook...
Sunday Night: No Operational Impact. NO SIG WX.
Monday: Low Operational Impact. Breezy. NO SIG WX.
Monday Night: Low Operational Impact. Breezy. Slight Chance of SHRA...SHSN.
Tuesday: Moderate Operational Impact. Chance of SHRA.
Tuesday Night: Low Operational Impact. Slight Chance of SHRA.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: Moderate Operational Impact. Chance of SHSN.
Thursday: Moderate Operational Impact. Chance of SHRA.
&&
.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 Eureka CA
251 PM PST Sat Feb 22 2025
.SYNOPSIS...Heavy rain is forecast for Del Norte and far
northern Humboldt Counties tonight. Elsewhere, generally light
rain is expected. A low pressure system will generate locally
strong and gusty southerly winds over the headlands and interior
mountains this weekend. Strong southerly winds will be possible
again on Monday.
&&
.DISCUSSION...A long fetch of deep layer moisture emanating from
the subtropics (PWATS over 1 inch) will intersect the coastal
terrain late today into tonight. Heavy rain is forecast for Del
Norte and far northern Humboldt Counties tonight. Hourly rain
rates around 0.30in/hr are probable (70-80% chance) in the
interior of Del Norte from 8 pm Sat to 5 AM Sun. Deterministic
convective allowing models such as the HRRR and ARW indicate
localized hourly rates approaching 0.50in/hr, likely the result
of topographic forcing. The brunt of this atmospheric river
(AR2/AR3) will be aimed north of the area with Del Norte on the
southern edge of the IVT plume max (500-600kg/m/s). Even though
the duration of the AR is over 48 hours, heavy rain rates do not
appear to last that long based on the latest HREF guidance. Even
moderate rain rates (0.20in/hr) fall off during the day on Sunday.
We still cannot rule out rainfall run-off impacts tonight. Minor
flooding will be possible tonight into Sunday morning. Also,
mud/landslides or rock falls will also be possible in the steep
terrain. Slides will most likely impact highway 199 in Del Norte
County and possibly highway 101 north of Klamath. For now will
highlight this threat in a weather story graphic and social media
post. Otherwise, rainfall be light to moderate for the remainder
of the forecast area. Southern Lake and southern Mendocino may
not get any measurable rain this weekend. Snow levels will remain
quite high this weekend, above 6000 feet and temperatures will
remain above normal even under thicker cloud cover.
Gusty south winds will develop along North Coast this afternoon
and evening as surface low pressure approaches the west coast and
gradients tighten. Strongest winds will be over the coastal
headland, especially Pt St George where gusts around 40 mph are
probable. The gusty winds should persist through Sunday.
A surface low is forecast to develop just outside 135W north of
40N Sunday as the quasi-stationary frontal boundary north of the
ORCA border buckles and a surface cyclone develops and rapidly
progresses NE outside 135W. Synoptic scale model guidance
continues to keep the strongest and most damaging winds with this
cyclone well offshore and just north of the forecast area, along
the Oregon coast. Surface pressure gradients will tighten up
again by Monday morning and stronger wind gusts to 50 mph are
probable for the coastal headlands and interior ridges as a 60kt
925mb southerly speed max develops in advance of the boundary.
All models have sped up the timing of strongest winds. ECMWF has
been clustering around Monday afternoon/evening, but latest
run has shifted earlier in the day. ECMWF ensemble mean wind
gusts is over 50 mph for Pt St George and KCEC airport. In fact
there are many members, 30% of 100, over 55 mph from 4 AM to 4
PM Mon. Looking at the NBM, 90th percentile max gusts are on the
order of 55 to 65 mph over the interior mountains of Del Norte
with lower probabilities for gusts to 55 mph for the Humboldt
interior mountains; specifically Kneeland and Berry Summit. Wind
this strong will make driving difficult and could knock down tree
branches. We are leaning toward a wind advisory for this event.
For now will hold off on hoisting an advisory multiple days out
and wait to see how deterministic models and ensemble data sets
trend. We will message the potential for hazardous winds in
weather story graphic and social media posts.
Precip will end on Tuesday as a broad upper ridging quickly
springs back and holds into mid week (Wed). The ridge aloft with
above normal 500mb heights will likely remain the dominant feature
controlling NW California weather into late next week. Temperatures
will remain above normal. DB
&&
.AVIATION...Conditions at the coastal terminals will continue to
devolve as rain showers move onshore ahead of an approaching
surface front. MVFR ceilings and periods of mist are being
observed alongside increasing winds - already gusts 20-25 knots at
CEC this afternoon. AR moisture will funnel into northern
Humboldt and Del Norte county through Sunday morning, generating
moderate to heavy rainfall and wind gusts 35 to 40 knots along
exposed coastal areas. A prominent risk of windshear is expected
beginning this afternoon as winds aloft within the LLJ exceed 50
knots at 1500 to 2000 feet. Periods of IFR to LIFR ceilings and
visibility`s are possible with heavier downpours. There is a
chance for light rain showers at UKI early Sunday morning, but
accumulations will be very minimal (<0.20 inch) and winds should
remain light. Even as the first round of rainfall begins to
diminish Sunday afternoon, winds will remain elevated beneath an
active upper troughing pattern. A stronger front is expected to
move across the north coast Monday morning.
&&
.MARINE...Increasing southerly winds will combine with a decaying
mid- period westerly swell to produce steep and hazardous seas
through the weekend, especially in the northern waters. Gale force
gusts are expected in the northern waters late tonight night into
early Sunday morning as a fast-moving frontal boundary moves
onshore. Responsive 7 to 9 foot wind waves will enhance already
elevated seas through Sunday. An active upper trough pattern will
sustain elevated southerlies through early next week. Confidence
is increasing in a stronger front arriving Monday afternoon;
potential for gale force gusts exceeding 40 knots will coincide
with the arrival of a large, long period westerly swell 17-18 feet
at 14 seconds.
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
Small Craft Advisory until 6 AM PST Monday for PZZ450.
Small Craft Advisory until 3 PM PST this afternoon for
PZZ455-470-475.
Gale Warning until 3 PM PST Sunday for PZZ470.
&&
$$
Visit us at https://www.weather.gov/eureka
Follow us on Facebook and Twitter at:
https://www.facebook.com/NWSEureka
https://www.twitter.com/NWSEureka
For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png
Area Forecast Discussion
National Weather Service Marquette MI
555 PM EST Sat Feb 22 2025
.KEY MESSAGES...
- Widespread light wintry mix anticipated ahead of a clipper
system Sunday night into Monday. Rain and snow are expected
with a 15% chance of a light glaze of freezing rain prior to
the Monday morning commute.
- Warmer than normal temperatures through the first half of
next week with highs likely above freezing. A colder pattern
possibly shapes up into next weekend.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 249 PM EST Sat Feb 22 2025
Water vapor imagery and RAP analysis show nw mid-level flow into the
Great Lakes this aftn. A couple of shortwaves embedded in this flow
have produced some areas of -sn across Upper MI today, mainly across
western and northern Upper MI. Current temps range thru the 20s to
the lwr 30s F.
Shortwave currently nw of Lake Superior will pass across the area
this evening. Until passage, some areas of -sn/flurries will
continue. Last of the -sn is about to depart the Keweenaw, and it
will exit the eastern fcst by midnight, if not sooner. Sfc trof
dropping s across Lake Superior tonight will end up over southern
Lake Superior or just into northern Upper MI. Might be some flurries
associated with it, but since air mass is not cold enough to support
lake effect shsn, did not include any mention of pcpn with the trof.
Expect min temps mostly in the upper teens to mid 20s F, but
traditional interior cold spots may slip to the lower teens F.
&&
.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 421 PM EST Sat Feb 22 2025
Outside a few morning flurries, dry weather is anticipated on Sunday
as light winds become S by the afternoon and gradually increase
through the day. With WAA, some above normal highs are anticipated
in the 30s to low 40s with most warming at least to freezing. This
also helps gusts in S downslope areas approach 20 mph by Sunday
evening...gusts up to 20-30 mph are possible (50% chance) Sunday
night into Monday as a 35-45 kt LLJ passes overhead.
A shortwave and approaches from the NW Sunday night, sending clipper
low over far N Ontario Sunday night through Monday. WAA ahead of it
increases cloud cover from the W Sunday afternoon and supports light
precip Sunday night into Monday. Model soundings leave little
confidence in p-type as profiles do show a warm nose between
900-850mb, but there is a wide range of solutions regarding
p-types and timing of them. Favored the NBM p-type solution
given the low confidence, but a wintry mix of rain and snow is
expected. The 2/22 12Z HREF indicates between a 20-50% chance
for up to 0.01" of ice from freezing rain ahead of the Monday
morning commute, but the NBM probs are lower around 10-20%.
While the NAM/NAM Nest/GFS deterministic solutions place up to
0.03-0.06" over parts of the north-central and east, the
HRRR/RAP solutions of just a light glaze are the more likely
solution as the inversion is not particularly noteworthy.
Otherwise snow accumulations should be limited to a few
hundreths on the high end in Keweenaw, Alger, Schoolcraft, and
Luce counties. This wintry mix combination could impact the
morning commute on Monday. Will need to continue to monitor this
risk as it approaches; future forecast packages could include
an SPS for potential slippery road conditions. Highs on Monday
are expected in the upper 30s to mid 40s, but could push near
50F if MOS guidance is correct.
Trailing rain/snow chances (15-25%) continue Monday into Tuesday as
the shortwave moves overhead. Another shortwave travels quickly
behind it, sending the lingering sfc trough S. With limited moisture
and unimpressive forcing, impacts are not expected as QPF struggles
to reach 0.01"/6hr. The remainder of the forecast suggests the NW
flow sends additional shortwaves over the area with associated
clipper systems. Spread on sfc track/timing in the ensemble guidance
remains so the NBM solution was left as is Tuesday night onward. The
two periods of higher PoPs are Wednesday and then Friday into
Saturday. With the warmer airmass still in place on Wednesday highs
will be in the 30s to low 40s with lows in the 20s. This keeps rain
chances in the mix on Wednesday, but chances for rain diminish into
next weekend as potentially a colder airmass settles in. The GFS
currently is the colder solution, leaning toward mainly snow for the
system into next weekend while the ECMWF remains more mild. There is
better consensus for cooler temps late next weekend into the
following week which could bring LES back to the UP on Sunday.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 554 PM EST Sat Feb 22 2025
Afterwards, expect VFR to prevail at all terminals through most of
the period. CMX will briefly go MVFR late Sunday morning into early
Sunday afternoon.
&&
.MARINE...
Issued at 421 PM EST Sat Feb 22 2025
W to WSW winds of 15-25 kts this afternoon gradually settle below 20
kts this evening, becoming light and variable tonight into Sunday
morning. Winds then become S, increasing to 20-30 kts over the E
half and 15-25 kts over the W half ahead of a clipper low passing
over N Ontario. Winds over the W half increase to 20-30 kts by
Monday morning as winds across the lake veer W for the remainder of
the day. There is a 10-30% chance for gale force gusts to 35 kts
late Sunday night into Monday. Waves are expected to peak around 6-8
ft N and NE of the tip of the Keweenaw Peninsula on Monday. W winds
settle to 15-25 kts by Monday evening, falling below 20 kts by
around midnight Monday night. Winds then remain near or below 20 kts
for much of the week with uncertainty regarding the path of any
potential clipper lows through next week. Should a low pass directly
over the lake, gale potential would increase to 20-40%, but there is
much uncertainty regarding timing any low pressure passages at this
time.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...Jablonski
AVIATION...07
MARINE...Jablonski
Area Forecast Discussion
National Weather Service Phoenix AZ
414 PM MST Sat Feb 22 2025
.UPDATE...Updated Aviation Discussion.
&&
.SYNOPSIS...
Above normal temperatures will prevail through the next 7 days. A
warming trend will carry us into next week, with afternoon high
temperatures reaching the lower 80s by Sunday and upper 80s to
near 90 degrees during the middle of next week. Aside from periods
of higher level clouds over the next week, dry conditions will
continue.
&&
.DISCUSSION...
A dry shortwave is shown in the latest RAP 500 mb analysis exiting
AZ to the east early this afternoon. Meanwhile, mid-level wv imagery
reveals a N-S elongated, innocuous disturbance dragging some cirrus
over the state from the WNW today. These shortwave disturbance have
done little to suppress the broad area of positive H5 height
anomalies aloft, and so we can expect continued above normal
temperatures across the forecast area today. Afternoon highs will
fall mostly in the middle-to-upper 70s across the lower deserts of
South-Central AZ, with some of the typically warmer locales out west
(e.g., Yuma, El Centro, and Blythe) nearing 80F. For Sunday into
early next week, global guidance shows the axis of an upper level
ridge shifting over the Southwest US, leading to warming
temperatures aloft. In fact, NAEFS mean 700 mb temperatures exceed
the 90th and at times 98th percentile of CFSR climatology over
the forecast area during the 24-48 hour timeframe. This will
translate to a rather quick warming trend at the surface across
the forecast area, with lower desert highs reaching the lower 80s
Sunday and middle 80s by Monday.
During the first half of the upcoming workweek, the upper level flow
will be characterized by a zonally extended North Pacific Jet
streak, strong negative height anomalies to the north of it, and
upper level ridging downstream over the Western CONUS. The north
Pacific jet will send several shortwaves downstream and over the top
of the ridge, acting to dampen the ridge somewhat as they pass well
to the north of our region. One shortwave ensembles show passing
well to the north on Tuesday has trended further south in the latest
ensemble runs, and so NBM highs on Tuesday have come down a couple
degrees. Temperatures are still likely to be warmer on Tuesday than
Monday, with highs in the middle-to-upper 80s over South-Central AZ,
and nearing 90F over the typically warmer areas of the western
deserts. The Wednesday-Thursday timeframe still looks to be the
warmest for the forecast area, with widespread lower desert highs in
the upper 80s to near 90F, approximately 15 degrees above normal
for the time of year.
By the end of the workweek and into next weekend, a pattern change
is expected, as the North Pacific Jet begins to retract and shift
equatorward. Upper level closed lows will begin to undercut the
ridge, bringing a more disturbed pattern to the Desert Southwest. An
initial closed low will be mostly dry, passing overhead possibly
Friday or Saturday, with timing differences apparent between WPC
Clusters. The main impacts from this initial systems will be locally
breezy conditions and the potential for elevated fire weather
conditions for the high terrain of South-Central AZ. Temperatures
should begin to trend down as well, though latest NBM shows them
remaining above normal through at least Saturday.
&&
.AVIATION...Updated at 2311Z.
South Central Arizona including KPHX, KIWA, KSDL, and KDVT; and
Southeast California/Southwest Arizona including KIPL and KBLH:
No weather concerns will exist through tomorrow morning under
clear skies. Trends in wind speeds and directions will be nearly
identical to the past 24 hours with the typical easterly shift in
the Phoenix metro late tonight, while N/NW directions will
prevail the majority of the period in SE California. There will
also be periods of calm and light variable winds at all terminals.
&&
.FIRE WEATHER...
High pressure will gradually overtake the region again this
weekend leading to warming conditions and continued low
humidities. Daily MinRHs of 10-15% will persist into early next
week with fair to poor overnight recoveries to around 25-30%.
Expect high temperatures to climb well into the 80s across the
lower deserts by Monday before peaking at around 90 degrees
during the middle part of next week.
&&
.CLIMATE...
Record high temperatures next week:
Date Phoenix Yuma El Centro
---- ------- ---- ---------
Feb 24 91 in 1904 93 in 1986 92 in 1986
Feb 25 92 in 1921 95 in 1986 94 in 1986
Feb 26 91 in 1986 96 in 1986 95 in 1986
Feb 27 92 in 1986 95 in 1986 96 in 1986
Feb 28 89 in 1986 97 in 1986 92 in 1986
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
DISCUSSION...Whittock
AVIATION...Ryan
FIRE WEATHER...Kuhlman CLIMATE...18