Area Forecast Discussion
Issued by NWS Goodland, KS
Issued by NWS Goodland, KS
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
936 FXUS63 KGLD 300756 AFDGLD Area Forecast Discussion National Weather Service Goodland KS 156 AM MDT Tue Apr 30 2024 .KEY MESSAGES... - A marginal to slight risk for severe thunderstorms continues for areas east of Highway 25 on Wednesday afternoon and evening. However, confidence is low at this time due to uncertainty on the location of a warm front which will determine where storms will develop. - Near critical fire weather conditions are possible Friday afternoon south of Interstate 70 and west of Highway 27. - Near critical to potentially critical fire weather conditions are forecast Monday afternoon for locations generally west of Highway 27. && .SHORT TERM /THROUGH THURSDAY NIGHT/... Issued at 220 PM MDT Mon Apr 29 2024 Latest surface analysis shows a warm front from the Nebraska panhandle into northwest Kansas and a new lee trough developing in northeast Colorado. At 500 mb, seeing zonal flow with some weak embedded waves. Visible satellite imagery shows some scattered CU across the area with strong surface heating. However bases are at around 10kft so only the occasional virga on radar. Tonight, expecting mostly clear skies with surface winds turning towards the southeast and gradually increasing. Low temperatures will be in the 40s to lower 50s. Tuesday, shortwave trough rotating around the base of an upper low in the northern Rockies will force a surface cold front through the area in the morning. Winds will shift to the northwest behind the front with gusts up to 35 mph in northwest corner of the area (Yuma County) and 20-30 mph across the remainder of the area. Afternoon relative humidity values of less than 15% have a fairly high probability of occurring for areas south of Interstate 70, but probabilities for wind gusts of greater than 25 mph are very low, as most of the wind is in the morning behind the front. So, not expecting any fire weather concerns due to the lack of wind in the afternoon. Despite the frontal passage, expecting high temperatures in the 70s to around 80. Tuesday night may see an isolated shower or two in the post frontal upslope regime into the higher terrain, but not much forcing otherwise. Low temperatures will be in the 40s. Wednesday, will start the day cloudy and cool with east to northeast surface winds. May be some fog as well. Old frontal boundary will start to return north as a warm front into south central Kansas during the afternoon. Models not in very good agreement on how far north the front will retreat. NAM in particular keeps the front south of the area with cloudy, cool conditions through the entire day. GFS a little further north but most of the area still capped, particularly north of the Interstate. All of this casts some doubt on severe potential Wednesday afternoon. Nonetheless, SPC keeps the eastern area outlooked with marginal to slight risks, assuming the warm front is further north. Deep layer shear will be sufficient for severe storms should that happen. Synoptic scale forcing will also be rather nebulous in the afternoon, with a broad southwesterly flow aloft ahead of a shortwave trough axis still over the central Rockies. As that wave comes out Wednesday evening, showers and isolated thunderstorms will increase in coverage, with the associated surface cold front serving as a focus. Models again are not in particularly good agreement for Wednesday night either. ECMWF is much wetter compared to the GFS with a swath of near 1" precipitation amounts along the front, while the GFS shows up to a half inch, mainly in southwest Nebraska. Either way, with the upper dynamics and front moving through Wednesday night should see the best chance for rain in the area. Temperatures on Wednesday will be highly dependent on what happens with the warm front, but for now NBM shows 70s and 80s across the area, but the NAM is notably cooler, especially north of Interstate 70 in Kansas and Nebraska, showing only 50s and 60s for highs. Low temperatures Wednesday night will be mostly in the 40s. Upper trough axis will be moving through Thursday morning with gusty northwest winds behind it. Both GFS and ECMWF show gusts to around 40 mph in the morning, gradually diminishing through the afternoon. Best chance for lingering showers will be in the morning. Highs will be in the 60s. A bit skeptical of the NBM shower chances Thursday night with lack of forcing and surface winds remaining downslope. Both the GFS and ECMWF are dry Thursday night. Low temperatures will range from the middle 30s in western areas to the lower 40s in eastern areas. Some patchy frost possible in eastern areas where vegetation is susceptible, but about a week early for frost/freeze concerns in western areas where typical last freeze dates are around May 7- May 10. && .LONG TERM /FRIDAY THROUGH MONDAY/... Issued at 154 AM MDT Tue Apr 30 2024 Upper level ridging over the area with low pressure centered in vicinity of ID/WY/UT Friday morning will have the area under southwesterly flow aloft. As the low pressure system progresses eastward, a front will sweep through the area in the Friday evening- Friday night timeframe, giving around a 30-50% chance for showers/ thunderstorms. Heading into the weekend, upper level ridging will build back in with flow becoming increasingly zonal while the next system comes into view off the west coast. Low pressure will skirt south of the area, then east on Sunday, and with the low level easterly upslope flow allowing for increased moisture into the area, at least expect to see some increased cloud cover but also potential for increased chances (up to around 20-25%) of showers/thunderstorms. As mentioned in prior discussion, there continues to be significant differences in guidance with regards to timing/placement of the early week low pressure system. Taking a look at ensemble members for 12Z Monday, placement of the upper low center ranges anywhere from still off the west coast to over the Desert Southwest to already encroaching on our area, with the jet streak working into our CWA. If the low is situated across the Desert Southwest/Four Corners region during the first half of the day Monday as currently suggested by majority of the GEFS ensemble members, could be looking at impactful weather day(s) for the start of the work week with possible hazards of gusty southerly to southwesterly winds, fire weather conditions, possible blowing dust concerns, thunderstorm potential followed by a frontal passage and wind shift to out of the north. Very low confidence at present in the potential for an early week multi- hazard event, so will continue to monitor for better consistency in guidance as this timeframe comes into closer range. For temperatures, looking at highs in the middle 60s to lower- middle 70s Friday and Saturday before warming into the 70s Sunday, and middle 70s to middle 80s Monday. For low temperatures, the forecast calls for middle 30s to upper 40s Saturday morning, low-mid 40s Sunday morning, middle 40s to middle 50s Monday morning, and low 40s to low 50s Tuesday morning. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 945 PM MDT Mon Apr 29 2024 KGLD...VFR conditions are expected through the period. A southeast wind around 10kts at taf issuance will continue through tonight. On Tuesday, south to southwest winds around 10kts in the morning quickly shift to the northwest by 15z, gusting up to 30kts or so through much of the afternoon. After 22z, northerly winds around 11kts veer to the northeast at similar speeds. KMCK...VFR conditions are expected through the period. A southeast wind around 10kts at taf issuance will continue through tonight. On Tuesday, a light southwest wind around 13z quickly shifts to the northwest by 16z-17z, gusting up to 30kts or so through the afternoon. After 00z, a northwest wind around 10kts veers to the northeast at similar speeds. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...None. CO...None. NE...None. && $$ SHORT TERM...JN LONG TERM...CC AVIATION...99