####018003349#### FXUS63 KUNR 170905 AFDUNR Area Forecast Discussion For Western SD and Northeastern WY National Weather Service Rapid City SD 305 AM MDT Fri Oct 17 2025 .KEY MESSAGES... - Clearing skies and mild temperatures today - Fast-moving system tonight/Saturday to bring showers and gusty northwest winds - Warm weather briefly returns for Sunday, then blustery and somewhat unsettled on Monday && .DISCUSSION...(Today Through Thursday) Issued at 259 AM MDT Fri Oct 17 2025 Water vapor imagery shows the storm system lifting NE across ND at this time. A weak wave is crossing far SE MT and rotating into the CWA, bringing light radar rain across NW SD into the northern Black Hills. Precip may be falling as snowflakes across the higher Black Hills, though no accumulation is expected. Early morning fog is shallow enough to dissipate early this morning. Midlevel subsidence will return this morning on the backside of the upper wave as it swings into the central Dakotas, clearing skies out across the CWA and bringing a quiet rest of the day. Temperatures will reach the upper 50s to upper 60s. Broad cyclonic flow persists across the northern Rockies/Plains as the next system dives down the backside of the trough. This clipper system will quickly push into the northern Plains Friday night. Latest trends show the vort max a tad farther south into eastern WY through western Neb, but still expecting precip with this system along with brief, strong cold air advection in the lower and mid levels. Steep lapse rates will support shower development behind the cold front, mainly through the Saturday morning hours. Not much QPF is expected with this...and snow accumulations across the higher Black Hills will be minimal. Decent pressure rises and ~40kt 700 mb winds transferring down to the surface will have the potential of bringing perhaps low end advisory winds to portions of the western SD plains. Highs will be in the mid 40s to mid 50s. Upper ridging will build across the region Saturday night and Sunday. Southwesterly flow/warm air advection will bring a thermal ridge across the northern Plains on Sunday, with highs reaching the 60s to mid 70s. The next system then moves in from the northwest Sunday night into Monday. Model are showing a strong cold front crossing the region Sunday evening, with gusty winds persisting through Monday. This will be our next shot for wind- related headlines, though the strongest winds may be just behind the frontal passage itself. Still much uncertainty with this. Not much QPF is expected across the CWA with this system. && .AVIATION...(For the 06Z TAFS Through 06Z Friday Night) Issued At 1016 PM MDT Thu Oct 16 2025 Upper low will push out of the region overnight, with lingering MVFR-IFR cigs trending to VFR by later Fri morning all places. Expect showers to end overnight across the western half with a few lingering showers possible Fri morning across the NW SD Plains. Breezy west winds and mostly clear skies expected by Fri afternoon, with the strongest winds across NW SD. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...None. WY...None. && $$ DISCUSSION/KEY MESSAGES...13 AVIATION...JC ####018004139#### FXUS65 KBOI 170906 AFDBOI Area Forecast Discussion National Weather Service Boise ID 306 AM MDT Fri Oct 17 2025 .SHORT TERM...Today through Sunday night...High clouds associated with an approaching upper level trough have overspread the area this morning. These clouds to not appear thick enough to prevent pockets of frost from developing in the Upper Treasure Valley east of Boise and the Western Magic Valley, with lows still expected to fall into the mid to upper 30s. The trough will move west to east across the Pacific Northwest just to our north later today bringing another day of breezy winds and mostly dry conditions. The only chance for precipitation (10 to 20 percent) will be in the West Central Mountains. High temperatures will increase a few degrees from yesterday, especially in southern areas, and will be near normal. Pockets of frost area again expected Friday night in the lower valleys as the clouds clear out and winds diminish behind the exiting trough.Consequently, the Frost Advisory has been expanded through the entire Treasure Valley into the Western Magic Valley for Saturday morning, with lows forecast between 33 to 37 degrees. On Saturday, an upper level ridge will briefly move overhead, bringing lighter winds and mostly sunny skies. Winds will start to increase Saturday night ahead of the next system. This upper level trough and its associated cold front will reach the area Sunday afternoon, bringing increased winds, cooler temperatures, and precipitation (30 to 60 percent chance) mainly to the central Idaho Mountains. Snow levels will fall to near 6500 feet for light snow, generally less than an inch. .LONG TERM...Monday through Friday...A trough will deepen over southern Canada and the Pacific Northwest on Monday, bringing cooler temperatures and high terrain precipiation. Snow levels will drop to 5000-6000 feet MSL, but the extent of the moisture will remain over Baker County and the West Central Mountains. Limited accumulation of precipitation is anticipated by Monday evening. The trough will then weaken and move east as a ridge of high pressure develops over the Western US. This will bring warm and dry conditions to the region through at least Thursday. After Thursday, ensemble variance increases in timing and extent of the next system. All solutions agree on some deep trough or closed low moving onshore late next week and bringing much cooler temperatures and widespread precipitation with an atmospheric river set up. Forecast confidence is low in exact impacts from this system, but the probability of valley rain and mountain snow with much colder temperatures is higher for Friday into the weekend. && .AVIATION...MVFR-LIFR in low stratus near the Magic Valley. Skies for the rest of the area are clear. Patchy valley fog may redevelop tonight near KBOI-KEUL-KMYL, though chances are low. Surface winds: variable less than 10 kt overnight, becoming W-NW 5-10 kt with gusts to 25 kt in the Magic Valley. Winds aloft at 10kft MSL: NW 20-35 kt. KBOI...VFR with mostly clear skies. Surface winds: SE 4-8 kt becoming NW 6-10 kt by Fri/18Z. Weekend Outlook...Mostly clear conditions on Saturday with patchy mountain valley fog in the AM. Sunday clouds increase with scattered showers north of a KBNO-KBOI line after Sun/12Z. Snow levels during precip drop from 8000 ft MSL Sun morning to 5000 ft MSL Sun evening. Surface winds: S-SE 5-15 kt Sat, and SW-SE 5-15 kt with gusts up to 25-35 kt Sun. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Frost Advisory from 9 AM this morning to 9 AM MDT Saturday IDZ012. Frost Advisory until 9 AM MDT Saturday IDZ014-016. OR...Frost Advisory from 9 AM MDT /8 AM PDT/ this morning to 9 AM MDT /8 AM PDT/ Saturday ORZ064. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise SHORT TERM...JDS LONG TERM....SA AVIATION.....SA ####018004714#### FXUS63 KGID 170907 AFDGID Area Forecast Discussion National Weather Service Hastings NE 407 AM CDT Fri Oct 17 2025 .KEY MESSAGES... - Pleasant weather today with highs in the 70s, sunny skies and light winds. - Northwest winds gusting 30-40+ mph expected behind a cold frontal passage Saturday. - Frost possible Sunday morning, most likely northwest of the Tri-Cities. - Near to slightly above normal temperatures Sunday onwards, with another round of gusty winds on Monday. && .DISCUSSION... Issued at 358 AM CDT Fri Oct 17 2025 Today... A few scattered showers are lingering across far eastern portions of the area this morning. A cold front currently located roughly along a Phillipsburg-Grand Island-Fullerto line and is slowly moving east through the area. By sunrise, the front will reside just east of the forecast area, with dry weather expected across the area. A cooler, but still seasonably warm day is forecast today, with highs in the 70s, coolest west of Highway 183. Today will see a break from the wind, with gusts generally at or below 20mph. Overall, a pleasant and sunny October day is in store for the area. Lows in the 40s are expected overnight. Saturday and Sunday... An upper-level trough over Manitoba/North Dakota will deepen and dive into the Plains/Midwest on Saturday. At the surface, another, more impressive cold font pushes through the area Saturday morning- early afternoon. Northwest winds quickly increase behind the frontal passage, gusting 30-40+mph. The ECMWF ensemble continues to be the most bullish on wind gusts, indicating a 40-80% for gusts over 40mph across the area. Most other guidance is slightly lighter, but still supportive of winds gusting 30-40mph. The northerly winds will also usher in a much cooler airmass into the area. Highs on Saturday vary depending on the timing of the cold frontal passage, ranging from the upper 50s in the north, to the low 30s in the south. The pressure gradient weakens Saturday night as the center of a high pressure system moves overhead. Under the high, clear skies and light winds are expected. Combined with the cooler airmass, temperatures will drop into the 30s Saturday night/Sunday morning and bring the seasons first chance for frost to the area. The current forecast has the best chances for frost northwest of the Tri- Cities where temperatures sink into the low-mid 30s. Frost looks to be more isolated/patchy across central/southeastern portions of the area but can't be ruled out. While there remains time for things to change, Frost/Freeze headlines may be needed Saturday night/Sunday morning. After a potentially frosty start to the morning, the high slides off to the southeast as warmer, southwesterly winds strengthen over the area. Highs in the mid 60s to low 70s are expected on Sunday, under sunny skies. Drier air remains in place across the area, as afternoon relative humidity values fall below 30 percent, which could bring some fire weather concerns to the area. The biggest limits on fire weather concerns Sunday will be marginal wind gusts and not fully cured fuels. Will continue to keep an eye on Sunday, as a trend up in winds could warrant an increase in fire weather concerns. Lows in the mid-upper 40s are expected Sunday night. Monday Onwards... A passing shortwave trough brings another cold front through the area on Monday. Similar to Saturday, windy weather is expected behind the front, gusting 30-40+mph. Highs on Monday will range from the low 60s to low 70s. Northwesterly flow sets up over the area through the end of the forecast period. Under this flow/regime, near to slightly above normal temperatures are expected (highs 60s/70s, lows 30s/40s), with breezy winds during the afternoon. The forecast remains dry through the end of the forecast period. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1236 AM CDT Fri Oct 17 2025 For KGRI/KEAR Airports: VFR conditions expected through TAF period. Winds become northwesterly behind a cold frontal passage this morning. LLWS will continue at KGRI through the cold frontal passage. Northwest winds around 10kts during the day on Friday. Winds become light around sunset and shift to the west-southwest. BKN-SCT mid level clouds are expected through sunrise, with skies clearing during the day on Friday. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ DISCUSSION...Davis AVIATION...Davis ####018002250#### FXUS65 KREV 170908 AFDREV Area Forecast Discussion National Weather Service Reno NV 208 AM PDT Fri Oct 17 2025 .KEY MESSAGES... * Dry and mild weather will prevail over the weekend with breezy winds Sunday afternoon. * Showers are possible in the eastern Sierra south of Tahoe on Tuesday. Otherwise, dry conditions persist into next week. * Unsettled weather may return late next week with impacts to travel and recreation possible. && .DISCUSSION... Transient high pressure will provide dry, quiescent weather and mild temperatures through the weekend. Slow warming through Sunday will yield weekend daytime highs in the mid/upper 60s and mid-70s for Sierra and W NV/NE CA communities, respectively. Weak low pressure will advance across the PacNW on Sunday, dislodging a dry cold front that sweeps through region Sunday night. Winds will become breezy Sunday afternoon in response, especially near the Oregon border where gusts may reach 30-35 mph at times. A few degrees of cooling is expected Monday in the wake of the cold front passage, although will still be on par to a bit above normal for mid- October. The first half of next week will likely be dry and mild as the Pacific storm track remains directed well north of the western states. However, discrete low pressure in the eastern Pacific will lift across southern California Tuesday, supporting a 10-20% chance of showers in Alpine and Mono counties Tuesday afternoon. There is still a convincing signal for a strong storm impacting the region late next week into next weekend with valley rain, heavy Sierra snow, and gusty winds all on the table. It's still far too early to give details with much confidence, but certainly worth keeping an eye on -- especially for those planning any outdoor activities or travel towards the end of next week. -Salas && .AVIATION... FZFG and IFR/LIFR conditions will be possible at KTRK this morning between 10Z and 16Z. Otherwise, expect widespread VFR conditions and light afternoon breezes. -Salas && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$