MIL-OSI USA: SPC Oct 11, 2021 Day 4-8 Severe Weather Outlook

1

Source: US National Oceanic and Atmospheric Administration

Day 4-8 Severe Weather Outlook Issued on Oct 11, 2021
Updated: Mon Oct 11 08:34:03 UTC 2021

 .

D4
Thu, Oct 14, 2021 – Fri, Oct 15, 2021
D7
Sun, Oct 17, 2021 – Mon, Oct 18, 2021
D5
Fri, Oct 15, 2021 – Sat, Oct 16, 2021
D8
Mon, Oct 18, 2021 – Tue, Oct 19, 2021
D6
Sat, Oct 16, 2021 – Sun, Oct 17, 2021
(All days are valid from 12 UTC – 12 UTC the following day)

Note: A severe weather area depicted in the Day 4-8 period indicates 15%, 30% or higher probability for severe thunderstorms within 25 miles of any point.
PREDICTABILITY TOO LOW is used to indicate severe storms may be possible based on some model scenarios. However, the location or occurrence of severe storms are in doubt due to: 1) large differences in the deterministic model solutions, 2) large spread in the ensemble guidance, and/or 3) minimal run-to-run continuity.
POTENTIAL TOO LOW means the threat for a regional area of organized severe storms appears unlikely (i.e., less than 15%) for the forecast day.

 Forecast Discussion

ZCZC SPCSWOD48 ALL
ACUS48 KWNS 110832
SPC AC 110832

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0332 AM CDT Mon Oct 11 2021

Valid 141200Z – 191200Z

…DISCUSSION…
While medium-range models are in general large-scale agreement that
a slowly progressive upper trough will traverse the entire U.S. from
west to east through the period, details of the advance of this
system — and thus the associated surface pattern, show fairly
substantial differences.

Along with the lack of confidence resulting from these model
differences, it would also appear that instability will be generally
modest in advance of the progressing surface cold front — which
would temper severe risk with this system.

This combinations of factors precludes inclusion of any
severe-weather risk areas, despite likelihood for thunderstorms that
will almost undoubtedly accompany the front as it shifts across the
U.S. through the period.

..Goss.. 10/11/2021

CLICK TO GET WUUS48 PTSD48 PRODUCT

MIL OSI USA News