September 2020 Forecasts and Discussions

[Typeing3]

Euro weeklies look ridgy thru late month.

[Abby_wx]

Potential record heat not only Tuesday, but also next Wednesday and Thursday now...

.LONG TERM /MONDAY THROUGH THURSDAY/...Model solutions remaining
consistent with strong upper level ridge over the area, 500 mb
heights 590 dms plus through the period. Low level flow turning
strong offshore later Monday into Tuesday with the offshore flow
continuing Wednesday before weakening Thursday. Model ensemble
high temperature member means continue to trend warmer with many
ensemble solution members Wednesday and Thursday going for highs
in the lower 90s in Seattle on both models. Model blend solutions
running about 5 degrees colder. Confidence increasing in the
warmer solutions. Will go with highs in the upper 70s and 80s
Monday warming to the 80s and lower 90s Wednesday and Thursday.
With the strong offshore flow even the coast will be very warm
with 80s Monday through Wednesday. Offshore flow coming to an end
Thursday will result in some cooling along the coast while little
change is expected over the interior. Record highs are likely
Tuesday through Thursday.

The record breaking heat combined with the strong offshore flow
will create critical fire weather conditions over Western
Washington beginning Monday and continuing through at least
Thursday. Potential gusty easterly winds in the Cascade foothills
will only make the situation worse. Next week will be the worst
fire weather conditions in Western Washington so far this summer.
Felton

[AbbyJr]

https://twitter.com/50ShadesofVan/statu ... 21377?s=20

[Typeing3]

Could be some warm nights next week with the gusty E/NE winds.

[Typeing3]

Noticed some haze/high level smoke in the sky today.

[AbbyJr]

Could be some warm nights next week with the gusty E/NE winds.

How strong of gusts do you think Abbotsford could see? Some models show around 60 km/h on Monday.

[Typeing3]

How strong of gusts do you think Abbotsford could see? Some models show around 60 km/h on Monday.

60 seems a bit high but definitely could see gusts in the 40-50km/hr range.

[VanCitySouth]

60 seems a bit high but definitely could see gusts in the 40-50km/hr range.

We are starting the a*** winds early this year aren't we?

[tyweather]

Looks like BC recorded a tornado in Fort St John last month

https://trib.al/PtVkToz

[AbbyJr]

Statements
3:55 PM PDT Saturday 05 September 2020
Special weather statement in effect for:

Fraser Valley - central including Chilliwack
Fraser Valley - east including Hope
Fraser Valley - west including Abbotsford
Gusty outflow winds are expected on Monday.

Following an abrupt change in weather conditions across the prairies this weekend, a strong ridge of high pressure will build over northern BC and spread southwards on Sunday night. Rising pressures will drive strong outflow winds through coastal valleys on the Labour Day Monday. Winds will likely be at their peak during the day but could potentially remain gusty through Monday night.

Wind gusts upwards of 70 km/h are possible leading to an increased risk of damage to/from tree limb breakage.

Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to BCstorm@canada.ca or tweet reports using #BCStorm.

Statements
3:55 PM PDT Saturday 05 September 2020
Special weather statement in effect for:

Metro Vancouver - central including the City of Vancouver Burnaby and New Westminster
Metro Vancouver - North Shore including West Vancouver and North Vancouver
Metro Vancouver - northeast including Coquitlam and Maple Ridge
Metro Vancouver - southeast including Surrey and Langley
Metro Vancouver - southwest including Richmond and Delta
Gusty outflow winds are expected on Monday.

Following an abrupt change in weather conditions across the prairies this weekend, a strong ridge of high pressure will build over northern BC and spread southwards on Sunday night. Rising pressures will drive strong outflow winds through coastal valleys on the Labour Day Monday. Winds will likely be at their peak during the day but could potentially remain gusty through Monday night.

Wind gusts upwards of 70 km/h are possible leading to an increased risk of damage to/from tree limb breakage.

Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to BCstorm@canada.ca or tweet reports using #BCStorm.

[Roberts Creeker]

Same SWS for upper and lower Sunshine Coast. Should be interesting. EC has a high of 26 on Monday, hottest temperature of the week.

[Rubus_Leucodermis]

That started out as pretty chilly air, so it’s going to be a very dry wind, which helps maximize the fire danger from this event. There’s already fire weather warnings out about that aspect on this side of the border.

[Abby_wx]

That started out as pretty chilly air, so it’s going to be a very dry wind, which helps maximize the fire danger from this event. There’s already fire weather warnings out about that aspect on this side of the border.

Seems like EC thinks it's going to retain some of that chill... they've backed off on the temperatures for next week. Still warm, but nowhere near records. Probably underdone...

Capture.PNG

By Monday, a high amplitude pattern will have evolved with the
development of a strong upper level ridge along the West Coast
into the nearby Pacific, with a strong shortwave trough digging
quickly into the Northern Rockies from Canada. Associated with
this shortwave will be a strong sfc cold frontal system that will
sweep across the PNW (a backdoor cold front), through the Rockies,
and Great Plains, with a 1035+mb high building in its wake (which
is rather impressive for Sept). As the sfc high drops from Canada
into the N Rockies thru the day Monday, a thermal trough will be
developing along the PNW Coast. Provided the strong gradient
associated with the strong sfc high, increasing N/NE winds are
expected thru the day west of the Cascade crest. These winds will
turn more easterly and peak Monday night into Tuesday before
gradually subsiding thereafter as the core of the sfc high
pressure continues to push SE. Provided an E-W oriented pressure
gradient and the development of breezy east winds, the downslope
component will also dry the area out, especially on Tuesday.
Critical fire weather conditions are expected to develop across
the area Monday and continue through Tuesday. Refer to the fire
weather section for more details. Heat will also be a issue, as
high temps top off in the mid-upper 80s (near 90 across southern
zones) and even into the 80s along the Coast.

Kovacik

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...Previous
discussion...High amplitude pattern will stick with us into the
long term as West Coast ridge remains in place and large scale
troughing develops across the central US. This will keep hot and
dry conditions in place across W Washington, with the hottest
temperatures of the week expected on Wednesday; near 90 to lower
90s across most lowland locations, with 80s expected near water.
Although gradients will have relaxed, a thermal trough along the
Coast and higher pressure to the east of the Cascades will still
yield dry east winds, likely continuing Fire Weather headlines.
The ridge looks to slowly break down to some degree on Thursday as
a shortwave moves across the Gulf of Alaska, but overall there
does not appear to be much change in the sensible weather as hot
and dry conditions persist.

[Typeing3]

EC seems to be going a bit conservative, but models have backed off on extreme heat. This event's duration (25c+ highs) is looking significant at this point though, given its September now.

Also If the NE winds continue to be brisk thru Monday night, we could also be looking at some impressively high overnight lows out in the valley.

[Typeing3]

00z GFS is bone dry thru September 21st.