Alert archive / Montana / Special Weather Statements in 2016

Special Weather Statement, NWS Missoula, MT

July 10, 2016Silver Bow County, Montana

NWS Missoula, MT issued this special weather statement at Jul 10, 2016, 1:45 PM MDT for Silver Bow County, Montana. It was in force for 45 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 10, 2016, 1:45 PM MDT (19:45 UTC)
Expired
Jul 10, 2016, 2:30 PM MDT
In force
45 min
Issued by
NWS Missoula, MT

County Silver Bow County, MT

The radar

The Missoula radar (KMSX), 184 km from the middle of the area, began a volume at 19:46 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Spokane, WA (KOTX), launched 12:00Z, 7.8 hours before the alert went out and 370 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Spokane, WA at 12:00Z on 2016-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 12:00Z on 2016-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1674 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
25 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Missoula, MT wrote its last area forecast discussion before this special weather statement went out at Jul 10, 3:48 AM MDT, 9 hours 57 minutes earlier.

Area forecast discussion, Jul 10, 3:48 AM MDT, 9 hours 57 minutes before
Area Forecast Discussion
National Weather Service Missoula MT
348 AM MDT Sun Jul 10 2016

...SIGNIFICANT RAINFALL AND COOL TEMPERATURES THROUGH MONDAY...
...HIGH ELEVATION SNOW TONIGHT INTO EARLY MONDAY...

.DISCUSSION...
Scattered showers and a few thunderstorms have been tracking
through north central Idaho and southwest Montana early this
morning. Stronger storms have been producing heavy rainfall, gusty
winds, small hail, and frequent lightning as they move
northeastward.

As the large low pressure system moves through our area today,
widespread precipitation with embedded thunderstorms are expected
due to high moisture availability. Initial heavy rainfall amounts
will focus around north-central Idaho and southwest Montana
today...and spreading northward to the rest of northwest Montana
by tonight into early Monday. This system will also keep
temperatures well below normal for those locations receiving
precipitation and thick cloud cover. Snow levels are forecast to
drop as low as 6500-7000 feet tonight into early Monday, resulting
in snowfall for high terrain. After all is said and done, valleys
could see over a half inch of rainfall while mountains could
potentially see 1-3" of liquid equivalent. The exception will be
far northwest Montana where precipitation will be limited due to
the low's track. Outdoor activities, especially those in the
backcountry, should prepare for wet and cool conditions.
Hypothermia and poor visibility will be large concerns for high
elevations.

As the low exits the region, a flat westerly flow will be over
the Northern Rockies Tuesday through Thursday. A subtle
disturbance is expected to swing through the region on Tuesday
which appears to cause scattered showers and thunderstorms over
Idaho county into southwest Montana during the afternoon and
evening. Wednesday and Thursday appear to be fairly dry with
temperatures steadily warming.

The models are starting to depict another large low pressure
system moving into the area by the weekend. The current models
runs have the track of the low farther to the north than the
current situation, so the bulk of the precipitation should be
north of the Canadian border with this next system. Temperatures
should cool to below normal readings once again this coming week.

&&

.AVIATION...Widespread showers, with embedded thunderstorms and
heavy bursts of rainfall, are likely for KMSO, KBTM, and KSMN
throughout today causing persistent, obscured terrain.
Showers and thunderstorms will spread northward toward KGPI after
11/0000. Rain will persist overnight for most locations,
particularly across southwest/west-central Montana and central
Idaho, and snow levels are anticipated to drop down to 6500-7000
feet. Ceiling and visibility reductions will be commonplace
throughout the day today into Monday.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

In the hours before

Special weather statement, Jul 10, 1:45 PM MDT, 0 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
145 PM MDT SUN JUL 10 2016

MTZ007-102030-
BUTTE/BLACKFOOT REGION MT-
145 PM MDT SUN JUL 10 2016

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN SILVER BOW COUNTY
UNTIL 230 PM MDT...

AT 144 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A STRONG
THUNDERSTORM OVER SILVER STAR...OR 17 MILES NORTH OF
SHERIDAN...MOVING NORTHEAST AT 45 MPH.

DIME SIZE HAIL AND WIND GUSTS OF 50 TO 55 MPH WILL BE POSSIBLE WITH
THIS STORM. THIS STORM HAS HAD A HISTORY OF PRODUCING A FUNNEL
CLOUD.

THOSE TRAVELING ON INTERSTATE 90 AND OVER HOMESTAKE PASS WILL
BE IMPACTED BY THIS STORM.

THIS STORM WILL REMAIN OVER MAINLY RURAL AREAS OF SOUTHEASTERN SILVER
BOW COUNTY.

LAT...LON 4574 11246 4576 11250 4575 11252 4571 11253
      4574 11261 4593 11243 4589 11240 4586 11243
      4585 11243 4579 11227 4577 11226 4575 11219
TIME...MOT...LOC 1944Z 224DEG 37KT 4570 11230

The office that day

Everything else NWS Missoula, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 9, 7:27 PM MDTSpecial Weather StatementMSOMissoula33 min
Jul 9, 8:31 PM MDTSpecial Weather StatementMSORavalli44 min
Jul 9, 8:54 PM MDTSpecial Weather StatementMSOGranite36 min
Jul 9, 9:06 PM MDTSevere Thunderstorm WarningMSORavalli39 min
Jul 10, 9:57 AM MDTFlash Flood WatchMSOLemhi9 hr

Nearby

Special Weather Statements in Montana, 2016Every special weather statement in 2016

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.