A fire which was an escaped agricultural burn grew to 13,500 acres 4 miles southeast of Malta. It began September 22nd and was controlled don September 27th.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PIH wrote it up.
A fire which was an escaped agricultural burn grew to 13,500 acres 4 miles southeast of Malta. It began September 22nd and was controlled don September 27th. It burned grass, brush and timber but caused no structural damage.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Pocatello, ID wrote its last area forecast discussion before the first event at Sep 22, 2:52 AM MST, 10 hours 8 minutes earlier.
Area Forecast Discussion National Weather Service Pocatello ID 352 AM MDT Sat Sep 22 2018 .DISCUSSION...Today Through Next Saturday. Slight ridging and SW flow will result in a dry, mostly sunny, warmer day across SE Idaho, with highs getting into the low-mid 80s across the Snake Plain, eastern Magic Valley, and Southern Highlands, cooler at higher elevations. Increasing winds today, especially at higher elevations, combined with widespread RH values of 9-15% necessitate continuance of a Red Flag Warning for the Central Mntns above 7,500 feet and the Caribou Highlands/SE CWA above 6,500 feet. Those critical fire weather conditions will be the main story today, with an otherwise excellent day for outdoor work, recreation, and agriculture. Patchy frost cannot be ruled out early this AM in the Upper Snake Plain and valleys of the Caribou Highlands, but surface temps are running warmer this morning compared to yesterday, so any issues should be quite isolated. Our next storm system and cold front is still progged to sweep across SE Idaho Sun eve, with really no major changes to precip expectations or timing noted in the guidance this AM. We continue to carry isolated showers north of Stanley and Challis very early Sun morning, expanding south/east toward Ketchum, Mackey, and Monida Pass by late morning, increasing in coverage/expanding along the MT border into Island Park during the afternoon, and ending during the eve in the Upper Snake Highlands and Teton Valley. Have nudged PoPs up to 35-50% in portions of the Central Mntns and MT border as confidence inches up that these areas will see the most shower activity based on good general agreement between the GFS and EC. The NAM continues to look too dry and was left out of the PoP and QPF blends this morning. Finally, nudged QPF totals down just a hundredth or two, with a general expectation of 0.03 to 0.10 inches with this event. Have continued mention of thunder Sun afternoon, but kept t- storm coverage isolated, and a more moist airmass should preclude reaching critical fire weather conditions. The big story next week continues to be a much cooler airmass advecting in behind Sunday's system, dropping temps into the 60s for Mon and Tues at most locations, colder as usual at higher elevations. Went ahead and added a little patchy frost to the grids Mon AM in the Snake Plain and other valleys, but Tues AM continues to be the period of greatest concern. The combination of clear skies/good radiational cooling, light winds, and N-NE flow may result in low temps reaching the 28-34 degree range across most of the Snake Plain as well as all of our northern and eastern valleys. This may result in a more widespread frost, and Frost Advisories or Freeze Watches are possible as we get closer. Additional, more patchy frost is possible Wed AM. Otherwise, long-range models are no longer suggesting any blocking ridge by mid to late week, instead keeping SE Idaho in closer proximity to an active NW flow shortwave track down the west side of a long-wave trough over the Central US. Several of these disturbances ride down the trough, but so far precip is expected to remain north and east of our area, and we maintain a dry forecast. A stronger low pressure trough may approach the region by Sat eve, but with some shifting in model solutions noted and this system being so far out, am not ready to jump on adding any showers to the forecast just yet. For the overwhelming majority of SE the coming week should be dry and pleasant, with only gradually/slowly warming temps. - KSmith/RS && .AVIATION... Southwest winds 10 to 20 kts in the Upper Snake Plain (KIDA and KPIH) this afternoon. Mainly SCT to BKN high clouds until this evening, then SCT middle level clouds this evening at KIDA and KDIJ. With upper trough passage on Sunday, VCSH expected at KSUN 22/18-24Z, but remaining VFR. - RS && .FIRE WEATHER... A dry front develops roughly over the central mountains early this afternoon and propagates into the Arco Desert by early evening. Gusty winds expected this afternoon over the Lemhi and Lost River Range with humidity below 15 percent. In the Caribou Forest, winds expected to develop late afternoon but should still see gusts to 25 mph. The Red Flag Warning remains in effect from 1300 to 2000 hours. The main disturbance moving inland on Sunday will bring a chance of showers and a slight chance of thunderstorms to the Salmon-Challis NF and northern Sawtooth NF during the morning hours, then move quickly into the Targhee NF during the afternoon and early evening. By midnight Sunday night the entire event should be east of the state. Precipitation should be less than 0.10 inch. Northwesterly flow pattern persists through the rest of the week. A few showers may develop along the Divide Monday, and there is low confidence in showers developing in the Salmon area next Saturday. - RS && .AIR STAGNATION... A continued progressive SW flow today along with surface winds of 15- 20 MPH gusting up to 25 MPH should continue to result in efficient transport and no major smoke/haze or degraded air quality issues across SE Idaho. Model guidance hints at the potential for a slight increase in smoke across the Snake Plain tomorrow (Sun), but a cold front Sun eve will produce breezy conditions, a wind shift into the W-NW, and usher in another fresh airmass. Thus, any smoke/air quality issues should be localized and tied to local active fires. The latest forecasts from Idaho DEQ generally keep air quality in the "Good" or GREEN category for the next 3 days region-wide, and we concur with this projection. - KSmith/RS && .PIH WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 1 PM this afternoon to 8 PM MDT this evening for IDZ413-422-476. &&
The national radar mosaic for the moment the first event began.
1 wildfire. Local standard time, as filed.
A fire which was an escaped agricultural burn grew to 13,500 acres 4 miles southeast of Malta. It began September 22nd and was controlled don September 27th. It burned grass, brush and timber but caused no structural damage.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2018Every state in 2018This day in weather historyWarnings in Idaho, September 2018
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 787715.