Flood Watch 9, NWS Missoula, MT

760 
WGUS65 KMSO 311613
FFAMSO

Flood Watch
National Weather Service Missoula MT
1013 AM MDT Thu May 31 2018

MTZ007-011800-
/O.CON.KMSO.FA.A.0009.180601T0000Z-180601T1800Z/
/00000.0.RS.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Butte/Blackfoot Region-
1013 AM MDT Thu May 31 2018

...FLOOD WATCH REMAINS IN EFFECT FROM 6 PM MDT THIS EVENING
THROUGH FRIDAY MORNING...

The Flood Watch continues for

* Flood Watch for Warm Springs Creek in Anaconda and Cottonwood
  Creek in Deerlodge and other small creeks in Deerlodge and
  Powell counties in west central Montana.

* From 6 PM MDT this evening through Friday morning

* Thunderstorms this afternoon and evening are expected to produce
  localized areas of heavy rain across the upper Clark Fork region
  of southwestern Montana. Up to 1 inch of rain, with isolated
  higher amounts will be possible. Area creeks and streams could 
  see a sharp rise due to rain and snow melt. Warm Springs Creek 
  near Anaconda and Cottonwood Creek in Deerlodge are already 
  running near bank full. As such, these two locations are a 
  particular concern for flooding. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$

543 
WGUS65 KMSO 011520
FFAMSO

Flood Watch
National Weather Service Missoula MT
920 AM MDT Fri Jun 1 2018

MTZ007-011630-
/O.CAN.KMSO.FA.A.0009.000000T0000Z-180601T1800Z/
/00000.0.RS.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Butte/Blackfoot Region-
920 AM MDT Fri Jun 1 2018

...FLOOD WATCH IS CANCELLED...

The Flood Watch for small creeks in Deerlodge and Powell counties
in west central Montana has been cancelled. Precipitation will
continue to decrease with significant rises on small streams and
creeks no longer anticipated.

$$

Area Forecast Discussion
National Weather Service Missoula MT
411 AM MDT Wed May 30 2018

......Strong to Severe Thunderstorms and Localized Heavy Rain for
Central Idaho and Southwest Montana...

.DISCUSSION...

Showers with isolated lightning strikes have begun streaming
across north-central Idaho and western Montana early this morning
associated with a low pressure system. These showers are
developing along a weak cold frontal boundary that is forecast to
stall across the area for the next two days. As a result,
instability and moisture along, and east of, this boundary will
contribute to widespread showers and thunderstorms for north-
central Idaho and southwest/west-central Montana this afternoon
and evening. Some storms are progged to become strong to severe,
with threats of damaging gusty winds, large hail, lightning, and
localized heavy rainfall creating rises in streams and creeks. In
particular, the best chance for storms to become severe will be
over southern Lemhi County, and far southwest Montana this
evening.

Widespread showers and thunderstorms will prevail across the area
Thursday into Thursday night as the stalled boundary and upper-
level dynamics support strong lift. The threat of flash flooding
from localized heavy rainfall will increase for southwest Montana,
west-central Montana, and central Idaho under this pattern due to
continuous storm development and abundant moisture. Again, gusty
winds, hail, and lightning will also be threats on Thursday,
though the severe threat is less likely. Please continue to
monitor important weather updates by visiting
www.weather.gov/missoula.

There will be one more round of showers on Friday, though these
will be much weaker and far less moist than those today or
tomorrow given that we'll be residing on the backside of an
exiting trough of low pressure. But it looks like we'll get at
least one nice day this weekend with all models showing a
seasonably warm and mostly sunny Saturday! However, this appears
short lived as yet another aggressive upper level trough begins to
dig into the Pacific Northwest. Models are not in good agreement
regarding the depth and strength of this approaching trough with
the ECMWF much stronger, slower and deeper than the GFS. Either
way, deepening southwest flow ahead of this approaching trough
presents an all too familiar scenario supportive of afternoon
showers and thunderstorms in both models on Sunday afternoon
across the Northern Rockies.

On Monday both the ECMWF and GFS show the beginning of a cool
down, though the frontal passage in the ECMWF is much stronger and
certainly could be more significant (heavy rain, thunderstorms &
gusty winds). By Tuesday morning the snow level will reside
between 5000 and 5500 feet, so much of the higher terrain could
experience some light snowfall with any remnant showers floating
around the base of this cold upper level trough. Cool and showery
conditions will be present into Wednesday and perhaps even
Thursday if the ECMWF is to be believed.

&&

.AVIATION...A cold front will continue to cross the Northern
Rockies early this morning, and is expected to stall across
north-central Idaho and southwest/west-central Montana today.
Rain showers will be a possibility for all TAF sites this
morning. Then, strong to severe showers and thunderstorms are
supported this afternoon and evening at KSMN and KBTM after 2100
UTC. Storms will be capable of producing gusty erratic outflow
winds and large hail in the vicinity of KSMN and KBTM, as well as
localized heavy downpours and frequent lightning.

&&

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