Alert archive / California / Mesoscale Discussions in 2016
Mesoscale Discussion 1
The Storm Prediction Center issued this mesoscale discussion at Jan 6, 2016, 9:32 AM PST for 4 counties in California. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 6, 2016, 9:32 AM PST (17:32 UTC)
- Expired
- Jan 6, 2016, 12:30 PM PST
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
Counties Los Angeles County, CA, Orange County, CA, Santa Barbara County, CA, Ventura County, CA
The radar
The Los Angeles radar (KVTX), 58 km from the middle of the area, began a volume at 17:33 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
Vandenberg AFB, CA (KVBG), launched 12:00Z, 5.5 hours before the alert went out and 167 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
- -12 J/kg
- Mixed-layer LCL
- 757 m above ground
- 0-6 km bulk shear
- 60 kt
- 0-1 km storm-relative helicity
- 163 m²/s²
- 0-3 km storm-relative helicity
- 333 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
110
ACUS11 KWNS 061732
SWOMCD
SPC MCD 061732
CAZ000-062030-
MESOSCALE DISCUSSION 0001
NWS STORM PREDICTION CENTER NORMAN OK
1132 AM CST WED JAN 06 2016
AREAS AFFECTED...COASTAL SOUTHERN CA
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 061732Z - 062030Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...THE POTENTIAL FOR LOCALIZED THUNDERSTORM-RELATED WIND
DAMAGE AND A FUNNEL/BRIEF TORNADO RISK IS LIKELY TO GRADUALLY
INCREASE/DEVELOP SOUTHEASTWARD THROUGH LATE MORNING AND AFTERNOON
ACROSS COASTAL SOUTHERN CA AND OFFSHORE AREAS.
DISCUSSION...CONSISTENT WITH MORNING VISIBLE SATELLITE IMAGERY AND
LATEST RADAR/LIGHTNING DATA...AN OFFSHORE PLUME OF STEEPENING
MID-LEVEL LAPSE RATES AND RELATED MODESTLY UNSTABLE AIR MASS WILL
DEVELOP INLAND ACROSS COASTAL SOUTHERN CA NEAR/BEHIND AN
INLAND-SPREADING FRONTAL BAND. NEAR/BEHIND THE FRONT...DIURNALLY
STEEPENING LAPSE RATES AND SURFACE DEWPOINTS NEARING 50 F WILL
SUPPORT INCREASINGLY STOUT LOW-TOPPED UPDRAFTS BY AFTERNOON WITH 0-3
KM CAPE REACHING/EXCEEDING 100 J/KG. IN THE PRESENCE OF GRADUALLY
STRENGTHENING LOW-LEVEL SHEAR/SRH BY EARLY AFTERNOON...THIS SCENARIO
WILL SUPPORT THE POSSIBILITY OF SOME SEMI-DISCRETE MINI-SUPERCELLS
AS WELL AS MORE PREVALENT INLAND-SPREADING SMALL BOWING SEGMENTS.
ACCORDINGLY...LOCALIZED WIND DAMAGE AND A FUNNEL CLOUD/BRIEF TORNADO
RISK SHOULD INCREASE BY MIDDAY AND EARLY AFTERNOON /MOST LIKELY
PEAKING IN THE 19-23Z TIME FRAME/ FOR NEAR-COASTAL/OFFSHORE AREAS OF
SOUTHERN CA.
..GUYER/HART.. 01/06/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SGX...LOX...
LAT...LON 34722041 34611960 34391812 33971753 33591725 33041742
32861852 33261979 34042059 34722041Nearby
Mesoscale Discussions in California, 2016Every mesoscale discussion 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.