Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/18/19
Area Forecast Discussion
National Weather Service Dodge City KS
613 PM CDT Thu Oct 17 2019
...Updated Aviation Discussion...
.SHORT TERM...(This evening through Friday)
Issued at 335 PM CDT Thu Oct 17 2019
As the next large scale upper level trough approaches the Rockies
tonight into Friday, a leeside trough in the lower troposphere will
continue to deepen. This will lead to increased south winds, even
into the overnight hours. In fact, we should continue to see 15 to
20 mph winds, occasionally above 20, through much of the overnight.
This will keep temperatures quite warm with overnight lows tonight
only in the 50s. On Friday, temperatures should warm quite a bit
into the lower to even mid 80s ahead of the advancing cold front.
The latest forecast calls for the front pushing south across much of
southwest Kansas around early evening, which should allow much of
southwest and even west central Kansas to reach 80s for highs.
Showers and thunderstorms are still forecast to develop along and
just behind the front at the surface, although surface-based
instability will be quite low. As such, the official SPC Day 2
convective outlook doesn`t even call for a Marginal Risk (only
General Thunder). POPs were increased to 40-50 percent east of U283
(60 percent from Stafford down to Medicine Lodge).
.LONG TERM...(Friday night through Thursday)
Issued at 335 PM CDT Thu Oct 17 2019
The cold front late Friday Night will only lower temperatures
Saturday about 15 degrees over that of Friday afternoon`s
temperatures. With the surface ridge overhead much of the day, winds
will be light -- a rather pleasant fall weekend day. South winds
will pick up again in speed Saturday Night to about 15 mph in
advance of yet another, even stronger Pacific storm system. This
storm will track north of western Kansas (again) as an upper low
develops out of the trough when it moves out across the Great Plains
Sunday Night. The result will be more dry downslope low level winds
in the dry intrusion sector of the storm. Sunday will be breezy if
not windy, depending on how the low level height gradient shakes out
Sunday afternoon. Certainly, it appears the strongest northwest
winds will be to the north and northwest of our southwest Kansas
forecast area. Monday may be the windier day for us, as the mid-
latitude cyclone occludes and the lower-mid tropospheric wind field
becomes more unidirectional (supporting better mixing). Yet another
storm system is poised to move across the Great Plains mid next
week, but there is quite a bit of uncertainty in how this storm will
play out, being Day 6-7 time frame.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 607 PM CDT Thu Oct 17 2019
VFR conditions can be expected tonight and Friday. High level
cloud cover overnight will begin to thicken and lower into the
5000 to 9000 ft AGL level by late day as an upper level trough
moves out of the Central Rockies and into the Western High Plains.
At the surface tonight southerly winds will continue at 15 to near
20 knots as a low level jet develops across western Kansas. RAP
and NAM BUFR soundings indicating wind speeds of around 50 knots
will be possible overnight in the 1500 to 2000 ft AGL level so
will be including a wind shear group from 03z to 12z Friday. Gusty
south winds at 20 knots will be possible through the day on Friday
ahead of a surface boundary that will move into Western Kansas
during the day. By late day this boundary will be located near
Liberal, Dodge City and Hays. After 21z a few widely scattered
thunderstorms will be possible along this boundary, especially
northeast of Dodge City and around the Hays area. Areas west and
north of this boundary the winds will be north at 10 to 20 knots.
&&
.FIRE WEATHER...
Issued at 335 PM CDT Thu Oct 17 2019
The Red Flag Warning remains in effect for 5 far southwest and west
central KS counties in the NWS DDC forecast area, even though the
wind speeds are only marginal. These winds will continue to pick up
in speed farther north in the Johnson to Syracuse area by sunset,
but the 3-hr criteria for Red Flag conditions may fall just short in
Hamilton and Kearny counties in particular. We will have to watch
for additional Red Flag conditions tomorrow afternoon, mainly in the
corridor from K25 to U283 where sustained southwest or west
southwest winds in the afternoon may be in the 15 to 20 mph range
with afternoon relative humidity falling to 15 to 20 percent. Near
critical to potentially critical fire weather conditions may be
developing behind the Sunday-Monday storm system as well, as an even
drier downslope airmass pushes into western Kansas from Colorado and
Wyoming.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 55 85 44 69 / 0 20 40 0
GCK 53 86 40 69 / 0 10 20 0
EHA 54 83 41 69 / 0 10 10 0
LBL 52 86 42 70 / 0 10 10 0
HYS 54 82 44 68 / 0 20 40 0
P28 52 78 49 72 / 0 20 60 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 7 PM CDT /6 PM MDT/ this evening for
KSZ061-062-074-075-084.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Umscheid
AVIATION...Burgert
FIRE WEATHER...Umscheid
Area Forecast Discussion
National Weather Service Medford OR
846 PM PDT Thu Oct 17 2019
.DISCUSSION...A cold front is moving onshore this evening and
currently stretches from around roughly Roseburg southwest toward
Brookings and then offshore. Rainfall is fairly continuous along
the front, but there are some breaks in it, and guidance shows it
continuing to break up as is moves inland this evening.
Nevertheless, rain is likely in most areas west of the Cascades
this evening. Additionally, snow is already falling in the
Cascades north of highway 140 and above 5500 feet, and this will
continue until the front moves through tonight. While we will see
a few inches of snow over the highest elevations like Crater Lake
tonight, it is still too warm to see much, if any, accumulations
down to pass level. The going forecast has this all covered, so no
updates are planned for tonight`s forecast.
Guidance is showing strong, gusty winds along and behind the next
frontal system as it crosses the east side Saturday. Snow levels
drop to around 5,000 feet behind this front Saturday, and this
should yield moderate snow accumulations in the Crater/Diamond
Lake areas. We`re working on both an east side wind advisory and a
winter weather advisory for the Cascades north of highway 140 for
Saturday that we expect to have out by 11 PM. -Wright
&&
.AVIATION...For the 18/00Z TAFs...From the Cascades west...Areas of
MVFR cigs and local IFR will continue in scattered showers and low
clouds with higher terrain obscured through this evening, with MVFR
becoming widespread tonight into Friday morning. Late Friday
morning, expect cigs to lift to VFR. East of the Cascades...VFR
conditions will prevail but expect areas of MVFR cigs to develop
tonight and Friday morning, clearing to VFR again Friday afternoon.
-CC
&&
.MARINE...Updated 800 PM PDT Thursday 17 October 2019...Long period
west swell will result in steep to very steep seas through tonight
with heavy surf and very dangerous bar conditions. Seas will remain
steep Friday and into the weekend. Another front Friday night will
bring a period of strong winds with seas remaining elevated. Weaker
fronts will follow into Sunday night, with offshore high pressure
and a thermal trough returning early to mid next week. -Spilde/CC
&&
.PREV DISCUSSION... /Issued 216 PM PDT Thu Oct 17 2019/
SHORT TERM...The band of showers from this morning that was seen
progressing into the west side has progressed east of the Cascades
and thinned out with scattered shower activity remaining over the
CWA early this afternoon. Another weaker, less extensive band of
showers is seen in satellite over the coastal waters inside of
130w. This will move onshore later today into this evening with
probabilities increasing again for west side showers. HRRR model
lightning threat indicates any lightning will remain north of our
area.
Friday`s weather will be uneventful and dry most areas as another
upstream system takes aim at western Oregon. Warm frontal showers
should develop over the Oregon side of the area by late afternoon
and into evening as a surface low deepens at about 127W offshore
from Coos Bay after sunset. As a result of this low moving onshore,
South winds will become fairly gusty along the Coos coast from
mid to late evening. In addition, precipitation will increase
over the area with local significant rates over the Cascades.
The low will move inland through eastern Washington Saturday
morning and cooler air will filter into western Oregon with moist
westerly upslope flows into the Cascades. Snow levels dip to
around 5000 feet. New snow totals near Crater lake should be
upwards of a foot so we`ll be highlighting some travel issues
likely in that area, especially Saturday morning. Stavish
LONG TERM...Monday through Thursday Night...Most of the area
will remain dry next week, with the exception of the coats and the
Umpqua basin, which could see some periods of light showers
Monday and into Tuesday night. This would result from a stalled
out thermal boundary just to our north, which may or may not
fluctuate slightly south, pushing a band of moisture into northern
Coos and Douglas Counties. Unfortunately, there is a wide range
of north to south variability in model and ensemble solutions, so
confidence is low, so have left a slight chance of showers in that
area.
Otherwise, upper level ridging will be in control, with drying and
warming conditions expected by the middle of next week. We are
getting into the season for fog, and with recent rainfall, shorter
daylight, and lowering sun angle, chances are good for late night
and early morning fog formation in many of the area valleys. Also of
note, a possible Chetco effect could push temperatures well above
normal for the southwest Oregon coast near Brookings, but the
strength of those offshore winds remains uncertain at this time.
-BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...High Surf Advisory until 5 AM PDT Friday for ORZ021-022.
CA...None.
Pacific Coastal Waters...Small Craft Advisory until 11 AM PDT Sunday for
PZZ350-356-370-376.
Hazardous Seas Warning until 5 AM PDT Friday for
PZZ350-356-370-376.
$$
Area Forecast Discussion
National Weather Service Marquette MI
740 PM EDT Thu Oct 17 2019
.SHORT TERM...(This evening through Friday)
Issued at 255 PM EDT THU OCT 17 2019
A broad central CONUS ridge pushed low pressure, now nearly
vertically stacked, to New England and RAP analysis indicates the
sfc ridge is now right over the west-central Upper Peninsula.
Despite this, modest northerly flow has continued today, and with
850 mb temps of -3 to -5C, there`s been ample moisture for mostly
cloudy skies across the region. Lake effect rain showers have also
continued over primarily the north central UP. Initially there was
some banded structure to these showers but this afternoon it`s taken
on a more cellular nature. Expecting this activity to end later this
afternoon or early in the evening as winds continue to diminish and
850 temps begin to warm.
Clouds will begin to scatter out overnight and winds will become
light to calm across much of the area. With mid-levels drying out,
should be ample radiational cooling where skies are able to clear
and low temperatures will tank into the upper 20s inland, with low
to mid 30s expected lakeside. There could be a few spots that stay
cloudier and thus warmer tonight, with better chances of this
happening over the east. There is also a slight chance for patchy
fog/freezing fog to develop but confidence is low at this time.
Upper level clouds will begin to fill in during the day Friday as
the anticyclonically curved jet moves overhead and some induced
upper divergence results. As a sfc trough moves across the northern
Plains during the day, the pressure gradient will tighten and flow
will increase out of the SE/SSE through the day. Wind gusts could
even approach 30 mph in a few spots in the afternoon, though
generally 15-25 mph gusts over the west half will be the rule. On
the bright side, warmer air will move in, with highs in the low 50s
east and mid to upper 50s west.
.LONG TERM...(Friday night through Thursday)
Issued at 429 PM EDT THU OCT 17 2019
Models suggest that a progressive pattern will prevail with ridging
over the Great Lakes on Friday giving way to a couple of sw flow
shortwave troughs this weekend into early next week as heights lower
across the northwest CONUS and then the Plains. A deep trough will
then develop across the central CONUS by Tuesday. Temps will
moderate with above average readings this weekend into Monday with
colder air moving in by Tuesday.
Friday night and Saturday, a shortwave trough and associated cold
front moving through the western Great Lakes should bring another
brief round of pcpn into the region. 700-500 mb fgen is likely to
support a band of rain into portions of Upper Michigan from west to
east Saturday. However, with limited moisture inflow
amounts should generally be light, at or below 0.10 inch.
Sunday, models remain in agreement that dry weather will prevail
ahead of a more significant system due in late Sunday night into
Monday. Mild conditions will continue with highs in the upper 50s to
around 60.
Mon, A stronger shortwave and sfc low is expected to develop and
approach the western Great Lakes by late Sunday night into Monday or
Monday night with more substantial rain and strong winds a good
possibility. Models and ensemble members have converged toward a
surface low track just west of Upper Michigan moving from sw MN at
12z mon to the MN arrowhead by 00z/tue. Confidence in the exact
forecast details is higher but some differences remain. The GFS/GEFS
bring pcpn faster than than the ECMWF/GEM. 300k isentropic with
strong moisture inflow with PWAT values above an inch in the warm
conveyor will bring a band of moderate to heavy rain through the
area. Rainfall amounts at least into the 0.50-1.00 inch range with
some locally higher amounts will be possible. Models indicated
potential for enough elevated instability to support a few tsra.
Tue-Thu, Colder air moving in behind the system could generate
blustery/windy conditions and lake enhanced/effect rain in the w-nw
wind favored Lake Superior belts, possibly mixed with snow at times
Tue night into Wed over western higher terrain as 850 mb temps drop
toward -3C to -5C. There may be a dry interval Wed before another
shrtwv and sfc low move into the region.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 740 PM EDT THU OCT 17 2019
VFR conditions will prevail at KIWD/KCMX thru this fcst period as a
drier/warmer air mass spreads over the area. Last of the lake effect
cloudiness/MVFR cigs should clear out at KSAW in the next couple of
hrs, leaving VFR conditions for the remainder of the fcst period.
Not out of the question that some shallow fog could develop at any
of the terminals tonight. KSAW would be the more likely terminal to
see shallow fog develop. S to se winds will become gusty to 15-25kt
during the day Fri.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 429 PM EDT THU OCT 17 2019
Friday afternoon into Saturday, winds will become southerly to
southeasterly over the lake ahead of an approaching trough that will
skirt to our north through Ontario to the Hudson Bay. Immediately
ahead of the trough, south winds of 20 to 30 knots are possible
across the central and eastern parts of the lake. Behind the trough,
winds become southwesterly around 20 late Saturday. Expect winds to
diminish below 20 knots early Sunday morning and throughout the rest
of the day. The relatively tranquil conditions will be short-lived
as winds increase to 25-30 knots on Monday, lingering though
Wednesday as a surface low exiting the Plains deepens as it tracks
over the Arrowhead of Minnesota and western Lake Superior. Given
that storm track, during early next week winds could exceed 30
knots, with southeast gales possible head of the system over eastern
Lake Superior and then strong west winds on the backside as it lifts
north into Canada.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...KCW
LONG TERM...JLB
AVIATION...Rolfson
MARINE...JLB