Area Forecast Discussion
Issued by NWS Cheyenne, WY

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910 FXUS65 KCYS 232017 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 217 PM MDT Thu May 23 2024 .KEY MESSAGES...
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- Strong wind gusts 50-60mph possible in the wind prone and gap areas of southeast WY today mid-morning through early afternoon. See the latest High Wind Warning Statement for further details. - Precipitation chances Saturday and Sunday before winds return Sunday. A much warmer, milder week ahead as an upper-level ridge overtakes the region.
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&& .SHORT TERM /THROUGH SATURDAY/...
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Issued at 203 PM MDT Thu May 23 2024 Current observational analysis continues to show a cold front moving through eastern Wyoming this afternoon. Light precipitation has developed across much of Carbon and Albany counties where Rawlins and Dixon have reported periods of light snow. Temperatures are expected to be some 20 degrees cooler across the counties compared to temperatures east of the Laramie Range the Nebraska Panhandle this afternoon. This front will continue to slide east and in its wake some elevated winds are progged to develop across much of the region. The arrival of some 50 knot winds aloft will mix down allowing for some wind gusts in the 40 mph range to occur across the wind prone areas. Signals suggest a Bora type wind event developing this evening across the Nebraska Panhandle thanks to a rapidly deepening low pressure system coming out of Colorado. Winds are expected to stay elevated across the Nebraska Panhandle through much of the evening and potentially into the early morning hours tomorrow before diminishing. This are will be monitored for the potential for quick fused High Wind Warning. Current wind highlights look on track with zones in the current High Wind Warnings have periodically gusted up to 58 mph, primarily across the Arlington wind prone zone. Expecting this High Wind warning to expire on time this evening. The pattern will shift to a more unsettled pattern as the flow aloft becomes an active NW flow with a few shortwave disturbances moving through late Friday and again on Saturday. Models still showing the shortwave on Saturday being the strongest with the better upper level dynamics. Question will be what is going on at the surface regarding moisture advection into the region ahead of this system. Still thinking we will see some isolated showers and thunderstorms Saturday afternoon during peak heating hours, but how strong or severe these storms become will depend on how much instability we can generate prior to the shortwaves arrival.
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&& .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
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Issued at 203 PM MDT Thu May 23 2024 An active weekend and start of the work week is expected until upper- level ridging begins to move overhead. This weekend, two shortwave troughs will push across the region. On Saturday an upper-level shortwave will move west to east across the CWA in the afternoon hours. Sufficient daytime heating will occur with 700mb temperatures increasing to the 5-6C range. Surface temperatures will warm into the mid-60s to mid-70s east of the Laramie Range and low-60s west of the Laramie Range. As the trough pushes through, enhanced lift will be present across the region. With weak CAPE across the Panhandle, some thunderstorms may be possible Saturday afternoon into the evening hours, with showers present across much of the rest of the CWA. Similarly, on Sunday another upper-level shortwave will push across the region, increasing precipitation chances once again. Little to no CAPE is currently progged to develop across the region, so thunderstorms may be difficult to sustain. As the trough passes aloft, 700mb height gradients are expected to tighten across the region, leading to Craig to Casper gradients in the upper-50s to low- 60s on Sunday. Strong winds will be favored at the wind prone regions of Arlington and Bordeaux once again on Sunday. Temperatures will be in the upper-50s to low-70s. Monday will be a transition day before calmer, warmer weather returns for southeast Wyoming and western Nebraska. On Monday, the second upper-level shortwave will push out of the region leading to briefly zonal flow followed by northwesterly flow as the ridge builds over the western CONUS. This northwesterly flow will be rather dry, leading to limited chances for precipitation on Monday. However, temperatures will begin to warm into the upper-60s to mid- 70s. Tuesday through Thursday will feature an upper-level ridge positioned directly over the region. Wednesday is expected to be the warmest day with highs in the mid-70s to mid-80s across the region. Many locations east of the Laramie Range will have the potential to reach 80F as 700mb temperatures warm to 10C. Mostly calm winds will present under this ridge with minimal clouds and precipitation chances. It will be a very nice mid-week, but things begin to chance late in the week as the upper-level ridge transitions into a trough for late Thursday and Friday. There is some disagreement between long range models at this time, with the ECMWF being a bit slower with getting the trough into the region and the GFS being much quicker. This will be something to monitor, but enjoy the nice, warm week ahead!
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&& .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
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Issued at 1010 PM MDT Wed May 22 2024 Intermittent MVFR/IFR conditions may impact the KRWL and KLAR terminals as an area of light snow showers moves across the area associated the frontal boundary. Areas ahead of this frontal boundary will see mainly VFR conditions, but post FROPA winds will become gusty and bring wind gusts between 40-45 knots to all terminals by the late afternoon through the overnight hours.
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&& .CYS WATCHES/WARNINGS/ADVISORIES...
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WY...High Wind Warning until 6 PM MDT this evening for WYZ101- 104>107-110-116-117. NE...None.
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&& $$ SHORT TERM...AW LONG TERM...AM AVIATION...AW