Alert archive / Arizona / Mesoscale Discussions in 2021
Mesoscale Discussion 1801
The Storm Prediction Center issued this mesoscale discussion at Oct 5, 2021, 3:53 PM MST for 8 counties in Arizona; Hidalgo County, New Mexico. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- Oct 5, 2021, 3:53 PM MST (22:53 UTC)
- Expired
- Oct 5, 2021, 5:30 PM MST
- In force
- 97 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 512
Counties Cochise County, AZ, Gila County, AZ, Graham County, AZ, Greenlee County, AZ, Maricopa County, AZ, Pima County, AZ, Pinal County, AZ, Santa Cruz County, AZ, Hidalgo County, NM
The radar
The Phoenix radar (KIWA), 68 km from the middle of the area, began a volume at 22:55 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
Tuscon, AZ (KTUS), launched 12:00Z, 10.9 hours before the alert went out and 95 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.
- Mixed-layer CAPE
- 4 J/kg
- Mixed-layer CIN
- -376 J/kg
- Mixed-layer LCL
- 2029 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 114 m²/s²
- 0-3 km storm-relative helicity
- 129 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted.
041
ACUS11 KWNS 052253
SWOMCD
SPC MCD 052253
NMZ000-AZZ000-060030-
Mesoscale Discussion 1801
NWS Storm Prediction Center Norman OK
0553 PM CDT Tue Oct 05 2021
Areas affected...Central and southeast Arizona and far southwest New
Mexico
Concerning...Severe Thunderstorm Watch 512...
Valid 052253Z - 060030Z
The severe weather threat for Severe Thunderstorm Watch 512
continues.
SUMMARY...The severe weather threat continues through the evening.
DISCUSSION...The initial arcing line of storms with embedded
supercells has mostly moved north of the best instability and thus
storm intensity has lessened. Scattered measured severe wind gusts
have occurred from earlier storm activity. Farther south, greater
instability remains with MLCAPE around 1000 to 1500 J/kg per SPC
mesoanalysis with effective shear around 35 to 40 knots. Therefore,
organized storms, including supercells remain possible through the
evening. Severe wind gusts remain the primary threat, but isolated
large hail or a brief tornado may also occur.
..Bentley/Thompson.. 10/05/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ABQ...EPZ...TWC...FGZ...PSR...
LAT...LON 34381240 35041095 34880998 33810892 32060813 31670814
31260817 31281109 31801278 32011344 32461335 34231341
34381240SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 5, 11:18 AM MST | Mesoscale Discussion | SPC | Coconino, La Paz, Maricopa, Mohave, Yavapai | 117 min |
| Oct 5, 11:46 AM MST | Severe Thunderstorm Watch | SPC | Coconino, Gila, Graham, La Paz, Maricopa, Mohave and 4 more | 8 hr |
| Oct 5, 1:55 PM MST | Mesoscale Discussion | SPC | Coconino, Gila, Graham, La Paz, Maricopa, Mohave and 4 more | 95 min |
Nearby
Mesoscale Discussions in Arizona, 2021Mesoscale Discussions in New Mexico, 2021Every mesoscale discussion in 2021
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.