Home   |    Current Conditions   |    Forecast   |    Weather Cameras   |    Climate   |    Weather Blog   |    About


Latest ZFP from WFO RIW
	
National Weather Service Local Forecast for Star Valley Ranch
Updated: 13 Dec 02:31 am MST

Overnight... A 20 percent chance of snow before 4am.  Mostly
cloudy, with a low around 5. Wind chill values as low as -5. South
southeast wind around 7 mph. 

Thursday... Partly sunny, with a high near 24. Wind chill
values as low as -5. South southeast wind 3 to 7 mph. 

Thursday Night... Partly cloudy, with a low around 2. Wind
chill values as low as -10. Southeast wind around 8 mph. 

Friday... Sunny, with a high near 24. Wind chill values as low
as -5. Calm wind becoming south southeast around 5 mph in the
afternoon. 

Friday Night... A 20 percent chance of snow after 11pm.  Mostly
cloudy, with a low around 20. South wind around 5 mph. 

Saturday... A 20 percent chance of snow before 11am.  Mostly
cloudy, with a high near 34. Light south wind. 

Saturday Night... Partly cloudy, with a low around 18. Light
southeast wind. 

Sunday... Sunny, with a high near 38.

Sunday Night... Mostly clear, with a low around 17.

Monday... Mostly sunny, with a high near 37.

Monday Night... Mostly cloudy, with a low around 21.

Tuesday... A slight chance of snow.  Partly sunny, with a high
near 33.

Tuesday Night... A chance of snow.  Mostly cloudy, with a low
around 23.

Wednesday... A chance of snow.  Partly sunny, with a high near
34.

	

Latest AFD from WFO RIW
	National Weather Service Riverton WY
212 AM MST Thu Dec 13 2018

.SHORT TERM...(Today through Saturday night)

Lee enhanced high clouds are already propagating south from
Montana as a sfc lee side trough extends south. High pressure will
build in from the west resulting in dry weather today and Friday.
Temperatures will warm aloft which will strengthen temperature
inversions in the valleys and basins through Saturday. H7 temps
will demonstrate a marginal temp gradient between YNP and the Cody
Foothills that will initiate elevated west winds in the Cody
Foothills today through Friday, especially around Clark. The temp
gradient will strengthen somewhat in this area saturday for
marginally strong winds in the Cody Foothills Friday night and Saturday.
A northern stream shortwave will help increase the gradient Friday
night and Saturday morning. This same shortwave will produce some
snow in Northwest Wyoming with light accumulations Saturday
morning.

.LONG TERM...(Sunday through Thursday)

Overview...Unseasonably mild and dry weather will prevail over
most of the area Sunday and Monday, except for shallow cold air
remaining in protected western valleys and lower central basins. A
strengthening westerly flow will bring chances of snow to the
west and the potential for high winds in the Absaroka mountains
and Cody Foothills Tuesday night into Wednesday. More benign dry
and mild weather will return on Thursday. Highs will mostly be in
the 40s to lower 50s across most of central Wyoming, with highs in
the 30s across the western valleys and lower portions of the Wind
River and Bighorn Basins.

Discussion...Upper high is expected to be centered over the
central Rockies on Sunday, and then progress into the Plains on
Monday as incoming Pacific trough splits along the west coast.
This system is expected to have minimal impacts on Wyoming with
northern stream energy staying north of our area and southern
stream low remaining well south across Arizona and New Mexico.

ECMWF and GFS continue to stick to their differing scenarios
Tuesday and Wednesday. The ECMWF continues to bring nose of 140
knot jet into NW Wyoming Tuesday night with fetch of Pacific
moisture on the south side of the jet pushing into western
Wyoming. GFS continues to push this energy further north over a
more amplified ridge across the Intermountain West. The Canadian
model is a closer match with the ECMWF, so we continue to give
this solution more weight until trends indicate otherwise. Thus,
chances of snow were maintained across the west mainly Tuesday
night into Wednesday morning, and we will continue to highlight
the potential for strong winds in the Cody Foothills in the
Hazardous Weather Outlook. Models including GFS 5-wave are
generally advertising the ridge amplifying over the Intermountain
West through the first part of next weekend with NW flow east of
the Rockies, indicating at least a quiet start to the first few
days of Winter. The Winter Solstice will occur at 323 PM MST on
Friday, December 21st.

&&

.AVIATION...(For the 12Z TAFS through 12Z Friday)

East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Routes

VFR conditions will prevail through the period. A gusty wind will
occur at KCPR and KCOD airports for most of the period.

West of the Divide...KBPI/KJAC/KPNA/KRKS Routes

Some snow showers will linger over the western mountains through 18Z
with local MVFR conditions and some obscuration. VFR conditions will
prevail at the terminal sites through the period. KRKS will see a
gusty wind today, decreasing after 01Z.

&&

.FIRE WEATHER...

A ridge of high pressure will move back over the area today
through Friday with warming mountain temperatures and returning
valley/basin temperature inversions. Areas of increased winds
will also blow at times through the period in the Cody Foothills,
especially on Saturday morning. All areas will see windy to very
windy conditions into this evening. Southwest winds will also blow
from the Red Desert to Casper through the period.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
	

Latest GFS MOS for JAC
	KJAC   GFS MOS GUIDANCE   12/13/2018  0000 UTC
DT /DEC  13            /DEC  14                /DEC  15          /
HR   06 09 12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 18 00
X/N                    23           5          29          17    36
TMP  18 14 10  8 17 21 20 15 12  9  8  6 17 26 27 21 20 21 21 31 32
DPT   9  7  4  3  6  7  7  9  9  7  5  4 11 15 13 13 19 18 18 19 19
CLD  SC BK BK BK FW FW BK FW CL CL CL CL CL CL CL OV OV OV OV BK BK
WDR  32 33 32 36 18 17 17 34 01 36 36 36 05 14 17 22 19 20 20 19 19
WSP  10 07 06 06 03 03 02 06 06 06 05 03 02 01 03 07 07 12 15 08 05
P06         2     4     0     0     0     0     0    11    28 18  3
P12                     4           0           0          34    18
Q06         0     0     0     0     0     0     0     0     0  0  0
Q12                     0           0           0           0     0
T06      0/ 2  0/ 0  0/ 0  0/ 0  0/ 2  0/ 0  0/ 0  0/ 0  0/ 1  0/ 0
T12            0/ 4        0/ 0        0/ 3        0/ 0     0/ 1
POZ   1  0  0  0  0  0  0  0  1  1  0  0  0  0  0  0  1  1  0  0  0
POS  96100100 97 98 98100 94 97 99100100100 96100 95 94 97 94100100
TYP   S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S  S
SNW                                 0                       0
CIG   8  8  8  8  8  8  8  8  8  8  8  8  8  8  8  8  7  6  6  6  8
VIS   7  7  7  7  7  7  7  7  7  7  7  7  7  7  7  7  7  7  7  7  7
OBV   N  N  N  N  N  N  N  N  N  N  N  N  N  N  N  N  N  N  N  N  N



615
FOUS24 KWNO 130000

-----------------

KJAC   GFSX MOS GUIDANCE  12/13/2018  0000 UTC
FHR  24| 36  48| 60  72| 84  96|108 120|132 144|156 168|180 192
THU  13| FRI 14| SAT 15| SUN 16| MON 17| TUE 18| WED 19| THU 20 CLIMO
X/N  23|  5  29| 17  36| 13  36| 10  36| 10  31|  7  34|  2  32  6 27
TMP  20|  8  27| 21  32| 16  32| 14  32| 15  28| 12  30|  6  27
DPT   7|  5  13| 18  19| 13  15| 11  20| 12  19| 10  14|  4  13
CLD  PC| CL  CL| OV  OV| CL  CL| CL  CL| OV  PC| PC  CL| CL  CL
WND   6|  6   5| 15  15|  7   6|  8   6|  7   5|  5   5|  6   5
P12   4|  0   0| 34  18|  5   4|  4   7| 12  13| 12  12|  5   5999999
P24    |      0|     34|      6|      9|     18|     13|     10   999
Q12   0|  0   0|  0   0|  0   0|  0   0|  0   0|  0    |
Q24    |      0|      0|      0|      0|      0|       |
T12   0|  0   0|  0   0|  0   0|  0   0|  0   0|  0   0|  0   0
T24    |  0    |  0    |  0    |  0    |  0    |  0    |  0
PZP   1|  1   0|  1   0|  1   1|  2   2|  1   0|  1   1|  2   1
PSN  95| 95  98| 93  98| 97  97| 86  94| 92  94| 93  95| 90  94
PRS   4|  1   2|  4   2|  2   3|  4   4|  7   5|  6   5|  8   6
TYP   S|  S   S|  S   S|  S   S|  S   S|  S   S|  S   S|  S   S
SNW    |      0|      0|      0|      0|      0|       |

	
Visible Satellite Loop

Regional Radar Loop

24-hour Precipitation Estimate

Current Surface Pattern

Current 500mb Pattern

Recent Salt Lake City Sounding

Latest Surface Chart

For the best information regarding Star Valley, go to: http:\\www.StarValleyWY.com © Copyright 2011-2018, Jack Hales.