Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/17/24
See below for an aviation forecast discussion for the 00Z TAFs.
&&
.SHORT TERM /THIS EVENING THROUGH THURSDAY NIGHT/...
Issued at 344 PM CDT Wed Oct 16 2024
The 20Z surface map showed low pressure over MT and southern
Alberta/Saskatchewan with large high pressure centered across MO. In
between these 2 systems, the tight pressure gradient continues.
Winds have been breezy out of the south with gusts of 25 to just
over 45 mph for much of the day. Even after we lose the daytime
mixing today, winds will remain elevated. A low level jet just above
the surface will help bring winds gusting over 45 mph to the higher
elevations and eastern slopes of the Prairie Coteau/Sisseton Hills
areas. A Wind Advisory has been posted for this area into Thursday.
Fire weather concerns continue. Very dry grasses and brush from
limited rainfall, relative humidity values in the 17 to 25 percent
range this afternoon, and the strong winds gusting out of the south
25 to 45 mph have resulted in critical fire weather. Red Flag
Warnings continue into the early evening hours today, and will be
picked up again Thursday from south central SD through eastern SD
and west central MN. The difference tomorrow will be a slight
decrease to the winds. This will be as the MT low shifts across the
central Dakotas and gets reinforced by an additional low from
western NE. The associated cold front will set up over central SD
Thursday afternoon, with winds shifting out of the west and
diminishing over north central SD.
The area of low pressure will only slowly exit over southeastern
South Dakota an central Minnesota by Friday night. Unfortunately,
breezy winds out of the north will return to central South Dakota
Friday afternoon. Still, additional moisture will move into the
area, with a 50 percent chance of light showers Thursday night west
of the James River Valley.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 344 PM CDT Wed Oct 16 2024
Surface high pressure anchored over the southeast CONUS will create
a bit of a block for us as the wave coming in splits with the cut
off upper low moving towards the 4 corners region and a weak
shortwave moving to our north. The cold front that moves in comes in
two waves of cold advection, the first before the start of the long
term (Thursday night) with a second reinforcing shot of colder air
coming in from the western Dakotas through the course of the day
Friday. Deterministic guidance has the front stall in the far
eastern CWA by Friday afternoon, with limited QPF showing up along
this feature, likely the result of the developing split flow regime.
Probabilities are still relatively unchanged, about 40% for 0.1
inches and 30% for 1/4 inch, however the NAM has a noted lack of any
QPF (for the eastern 2/3rds of the state) and the associated BUFKIT
profiles indicate a lack of lift or saturation at any particular
layer for more than a few hours at a time. This is in line with
prior experiences with these type of split flow regimes/systems.
Will continue to run with the NBM/WPC until there is more sustained
evidence to the contrary. Gradient winds and a pressure bubble are
also noted associated features with the front, with the GFS/NAM
running at 11 and 8mb/6 hours respectively. Probabilities for 30mph
gusts are right around 50% with negligible probabilities for wind
advisory criteria. With it being a cooler, more humid airmass in the
post frontal environment, should be able to take a break from Red
Flag criteria, however gusty winds and ambient dry conditions means
we will still probably have to deal with elevated fire danger. Rest
of the forecast looks fairly mundane with mild air returning for
Sunday/Monday. Thereafter the re-integration of the upper low is
causing some divergence in the handling of the upper pattern for the
remainder of the extended between deterministic models.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 624 PM CDT Wed Oct 16 2024
Terminals KABR,KATY,KPIR,KMBG
With strong winds continuing over the next 24 hours, and stronger
winds above the surface tonight, low level wind shear remains in
the forecast for most locations tonight.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Red Flag Warning from 11 AM CDT /10 AM MDT/ to 7 PM CDT /6 PM
MDT/ Thursday for SDZ005>008-010-011-016>023-033>037-045-
048-051.
Wind Advisory until 3 PM CDT Thursday for SDZ007-008-011-020-021-
023.
MN...Red Flag Warning from 11 AM to 7 PM CDT Thursday for MNZ039-046.
&&
$$
UPDATE...Dorn
SHORT TERM...KF
LONG TERM...Connelly
AVIATION...Dorn
Area Forecast Discussion
National Weather Service State College PA
1103 PM EDT Wed Oct 16 2024
.SYNOPSIS...
Another day, another frosty freeze. A cold upper level trough
axis will move east through Friday, while a large ridge of high
pressure at the surface will then builds into the state and sets
up residence for several days. Clear skies with light winds will
support widespread frost or freeze conditions overnight and
again Friday morning. Fair and pleasant conditions will last
through the upcoming weekend and into early next week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Another night of potential frosts and freezes is underway, and
compared to Tuesday night, fewer clouds and much lighter wind
should seal the deal for most. We expect mins should touch
freezing in many places, including some of the Lower Susqhehanna
River Valley. But, not enough of an area/percentage of the land
to warrant a freeze warning at this time. No areas have yet
been chopped off the growing season (frost/freeze program still
active) in Central PA.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
After a frosty/freezy start, fair conditions will prevail
Thursday over central PA as high pressure builds closer to PA.
A slow moving cutoff low along the mid Atlantic seaboard will be
just far enough away to impact our southeast. But as a result,
there will be some wind kicking up on Thursday over especially
southeast sections where gusts into the teens are again
expected. Many areas will have nearly full sun for the aftn
helping temps to rise 5-10F higher than Wed over the NW, and
2-4F higher for the SE.
Nighttime brings another chance for freezing/frost conditions.
The threat will be a little lower for the SE with the wind
satying up a little higher (5-7MPH) thru the night. Cloud
coverage should be near zero for most places. That puts the N &
W into a good position for freezing (perhaps better than Thurs
AM).
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Medium range guidance continues to support fair and much warmer
conditions late this week into the weekend, as an amplified
upper ridge builds over the Eastern CONUS. Surface high
pressure and associated dry air mass building into PA should
result in efficient radiational cooling at night into next
weekend, with frost/freeze concerns through at least Friday
morning. Abundant sunshine and moderating temps aloft should
result in progressively warmer days with highs getting back
above average by Friday. GEFS 2m temp anomalies indicate max
temps should be 5-10 degrees above average by next weekend,
translating to 65-70F over most of the region with additional
warming likely into early next week.
Next chance at some precipitation is next Wednesday as a
northern stream shortwave and accompanying surface cold front
are forecast to push east through the Ohio Valley and into PA.
This will lead to an uptick of pops, mainly across the northwest
counties. However, coverage will be minimal and amounts light as
the front moves into a very dry airmass.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
Prevailing VFR conditions are expected throughout the entire
TAF period with high (~90%) confidence at all airfields outside
of BFD/JST where some MVFR ceilings will be possible overnight,
especially in the 09-12Z Thursday timeframe. At BFD/JST, cannot
rule out some lower-level (~2-4kft) ceilings forming with some
low-level moisture within stable air outlined in RAP model
soundings. There is some uncertainty on ceilings thickening up
enough to warrant MVFR thresholds, with SREF outlining a 40%/50%
probability of ceilings reaching MVFR thresholds overnight at
JST/BFD, respectively. Multiple runs of recent GLAMP guidance is
less insistent on MVFR ceilings being reached, thus have
outlined a SCT deck below MVFR thresholds to outline that there
will be some concern for ceilings to thicken up in this
timeframe, although lower confidence than in the previous TAF
package.
High pressure influence will keep conditions mainly clear after
any lower level clouds that are still lingering mix out
tomorrow morning, with VFR conditions after 14Z Thursday with
very high (~100%) confidence. Winds generally out of the north
will push upwards of 10kts in the LSV (MDT/LNS) with generally
closer to 5kts elsewhere throughout the afternoon hours before
decreasing into the evening hours.
Outlook...
Fri-Mon...VFR/no sig wx.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
Freeze Warning from 2 AM to 9 AM EDT Thursday for PAZ004>006-
010>012-017>019-024-027-028-033-034-037-041-042-045-046-
049>053-058.
Frost Advisory from 2 AM to 9 AM EDT Thursday for PAZ025-026-
035-036-056-057-059-063>066.
&&
$$
SYNOPSIS...DeVoir/Dangelo
NEAR TERM...DeVoir/Dangelo
SHORT TERM...DeVoir/Dangelo
LONG TERM...DeVoir/Gartner
AVIATION...NPB
Area Forecast Discussion
National Weather Service Topeka KS
549 PM CDT Wed Oct 16 2024
.KEY MESSAGES...
- High to extreme Fire weather conditions present today through
through Friday. Burning will not be advised as gusty winds
and low relative humidities could lead to erratic fire
behavior.
- Above average temperatures continue through the extended
forecast with highs in the 70s.
- Dry conditions persist through most of the forecast. Portions
of the area could see some much needed rainfall Sunday night
into Monday.
&&
.DISCUSSION...
Issued at 223 PM CDT Wed Oct 16 2024
Early this afternoon a deep upper trough was located along the US
east coast. An upper ridge extended from TX northward across the
central and northern Plains. An upper trough was moving onshore
across the Pacific Northwest. At the surface a ridge of high
pressure was located across MO into eastern KS.
Tonight through Thursday night:
The upper level trough will dig southeast across the great Basin
into the southwestern US and amplify. A strong H5 jet will lift
northeast across the central Rockies and Plains. A lee trough
across the high plains will deepen through the day and southerly
winds across the CWA will increase to 20 to 30 MPH with gust up
to 35 to 40 MPH. The western counties may flirt with wind
advisory criteria for a few hours Thursday afternoon. The gusty
southerly winds will continue into Thursday night.
Friday through Sunday:
The upper trough digging into the southwestern US will amplify into
a closed upper low and will get cutoff from the main polar jet
across southern Canada. The surface lee trough will shift
farther south across eastern CO and eastern NM. Winds on Friday
will continue to be gusty and the southerly winds will advect
residual moisture northward across the Plains. The stronger
ascent ahead of the upper low over the NM/AZ border will cause
showers and and a few storms to develop across the high Plains
of TX, eastern CO, and western KS. At this time the rain showers
should remain west of the CWA.
Sunday night through Wednesday:
The closed upper low across NM will lift northeast across the
southern and central high Plains into central NE by 00Z TUE. The
DCVA ahead of the upper low should provide stronger ascent
along with residual moisture for scatted showers to develop
through the day on Monday. There may be enough instability to
hear a clap of thunder. The western gulf remains cut off due to
a surface ridge extending from the east central US, southwest
along the TX coast. So, without rich gulf moisture, QPF will
probably be less then 0.2 inches.
The extended range models have the closed upper low across NE
shifting east across IA into the southern Great Lakes and OH
River Valley on Wednesday. There may be a few lingering showers
Tuesday morning but as the upper low tracks northeast of the
region, the shower chances will end Tuesday afternoon.
Overall temperatures will be warm with highs in the mid to upper
70s. It looks as if we will be in a dry pattern as the main
upper jet will remain across southern Canada and the northern
Plains.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 549 PM CDT Wed Oct 16 2024
TAFS are a wind forecast. With dry air in place and moisture
slow to return on Thursday, skies should remain clear with
maybe some high CI moving in from the west late. Winds will be
the main driver of the forecast. Have maintained a mention of
LLWS for the pre-dawn hours. Speed shear of 30KT to 35KT is
progged from the RAP and NAM. With not much change in direction
there is some potential for the stronger winds to mix to the
ground limiting the speed sheer. But think the potential for
LLWS is high enough to keep in the forecast.
&&
.FIRE WEATHER...
Issued at 1005 AM CDT Wed Oct 16 2024
The red flag warning will continue through 7 PM across north central
Kansas. Southerly winds will continue to increase to 15 to 20 MPH
with gusts of 25 to 30 MPH, and minimum RHs will be in the 17 to 20
percent range. The RHs will increase above 30 percent and the wind
gusts will diminish after 7 PM.
Thursday, the surface winds east of the lee trough and west of a
surface ridge axis will increase to 20 to 30 MPH during the late
morning and through the early evening hours. The residual
moisture return may overcome the deeper mixing and only allow
minimum RHs to drop to a 19 to 25 percent range. However, since
fuels are very dry after the hard freeze, the environment will
be conducive for wild fires across the entire region. Therefore
the fire weather watch has been upgraded to a red flag warning
from 11 AM until 8 PM.
Friday into the weekend. Friday will continue to be breezy but the
continued advection of residual moisture north should keep minimum
RHs in the 25 to 35 percent range. Therefore the rangeland fire
danger index should only be high to very high across the region.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 7 PM CDT this evening for KSZ008-KSZ009-
KSZ020-KSZ021-KSZ034-KSZ035.
Red Flag Warning from 11 AM to 8 PM CDT Thursday for KSZ008-
KSZ009-KSZ010-KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-
KSZ026-KSZ034-KSZ035-KSZ036-KSZ037-KSZ038-KSZ039-KSZ040-KSZ054-
KSZ055-KSZ056-KSZ058-KSZ059.
&&
$$
DISCUSSION...Gargan
AVIATION...Wolters
FIRE WEATHER...Gargan