Alert archive / New Hampshire / Mesoscale Discussions in 2012
Mesoscale Discussion 960
The Storm Prediction Center issued this mesoscale discussion at May 29, 2012, 2:49 PM EDT for 5 counties in New Hampshire. It was in force for 56 min.
The area
The outline as issued.
The facts
- Issued
- May 29, 2012, 2:49 PM EDT (18:49 UTC)
- Expired
- May 29, 2012, 3:45 PM EDT
- In force
- 56 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
Counties Belknap County, NH, Carroll County, NH, Coos County, NH, Grafton County, NH, Merrimack County, NH
The radar
The Portland,ME radar (KGYX), 104 km from the middle of the area, began a volume at 18:51 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Gray, ME (KGYX), launched 12:00Z, 6.8 hours before the alert went out and 104 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
- 3 J/kg
- Mixed-layer CIN
- 0 J/kg
- Mixed-layer LCL
- 426 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 305 m²/s²
- 0-3 km storm-relative helicity
- 388 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
The text
As transmitted, in the capitals the NWS used until 2016.
692
ACUS11 KWNS 291849
SWOMCD
SPC MCD 291849
MEZ000-NHZ000-VTZ000-291945-
MESOSCALE DISCUSSION 0960
NWS STORM PREDICTION CENTER NORMAN OK
0149 PM CDT TUE MAY 29 2012
AREAS AFFECTED...NH AND FAR WRN ME
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 291849Z - 291945Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...THUNDERSTORMS ACROSS UPSTATE NY INTO VT WILL CONTINUE TO
PROGRESS EWD...BUT QUICKLY BECOME ELEVATED AND WEAKEN INTO NH AND
WRN ME. ALTHOUGH A FEW OF THESE STORMS MAY PRODUCE SEVERE
HAIL...LIMITED COVERAGE AND DURATION WILL PRECLUDE A WW ISSUANCE.
DISCUSSION...SEVERAL SUPERCELLS ARE ONGOING WITHIN THE WARM
SECTOR...WITH CONFIRMED REPORTS OF SIGNIFICANT HAIL AND DMGG WINDS
WITH THE STRONGEST STORMS. ALTHOUGH THE CONVECTION WILL SPREAD EWD
INTO NH AND ME...INSTABILITY BECOMES QUITE LIMITED EAST OF THE WARM
FRONT. WITH LINGERING STRATUS AND ANVILS OVERSPREADING THE
AREA...DESTABILIZATION IS NOT EXPECTED. ALTHOUGH A FEW STORMS MAY
PRODUCE SEVERE HAIL AS THEY CROSS INTO NH...A RAPID WEAKENING TREND
IS LIKELY.
..HURLBUT/WEISS.. 05/29/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BTV...
LAT...LON 44697162 45267118 45207071 44907074 44217091 43657127
43237155 43237201 43447219 44307196 44517154 44697162SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 29, 3:44 PM EDT | Severe Thunderstorm Watch | SPC | Belknap, Carroll, Cheshire, Coos, Grafton, Hillsborough and 2 more | 5 hr |
| May 29, 7:01 PM EDT | Mesoscale Discussion | SPC | Hillsborough | 89 min |
Nearby
Mesoscale Discussions in New Hampshire, 2012Every mesoscale discussion in 2012
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.