Alert archive / Massachusetts / Mesoscale Discussions in 2004

Mesoscale Discussion 2007

August 15, 20044 states

The Storm Prediction Center issued this mesoscale discussion at Aug 15, 2004, 4:42 AM EDT for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Aug 15, 2004, 4:42 AM EDT (08:42 UTC)
Expired
Aug 15, 2004, 6:45 AM EDT
In force
2 hr
Issued by
the Storm Prediction Center

Counties Barnstable County, MA, Bristol County, MA, Dukes County, MA, Essex County, MA, Hampden County, MA, Middlesex County, MA, Nantucket County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA, Worcester County, MA, Rockingham County, NH, Suffolk County, NY, Bristol County, RI, Kent County, RI, Newport County, RI, Providence County, RI, Washington County, RI

The radar

The Boston radar (KBOX), 72 km from the middle of the area, began a volume at 08:41 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

Brookhaven, NY (KOKX), launched 00:00Z, 8.7 hours before the alert went out and 116 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.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 00:00Z on 2004-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 66 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2004-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -5 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
66 J/kg
Mixed-layer CIN
-75 J/kg
Mixed-layer LCL
947 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
-5 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

175 
ACUS11 KWNS 150843
SWOMCD
SPC MCD 150842 
MAZ000-MEZ000-NHZ000-RIZ000-CTZ000-NYZ000-151045-

MESOSCALE DISCUSSION 2007
NWS STORM PREDICTION CENTER NORMAN OK
0342 AM CDT SUN AUG 15 2004

AREAS AFFECTED...COASTAL NEW ENGLAND

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 150842Z - 151045Z

AN ISOLATED TORNADO THREAT WILL EXIST ACROSS ERN NEW ENGLAND OVER
THE NEXT FEW HOURS AS HEAVY RAIN SPREADS INLAND ALONG THE IMMEDIATE
COASTAL AREAS.

REMNANTS OF HURRICANE CHARLEY ARE CURRENTLY MOVING ACROSS SRN NEW
ENGLAND. THE CENTER OF CIRCULATION IS PRESENT JUST SOUTHEAST OF LONG
ISLAND. THE CIRCULATION WILL MOVE ONSHORE ACROSS FAR ERN NEW
ENGLAND. ALTHOUGH INSTABILITY IS WEAK...0-6 KM SHEAR VALUES OF 50 TO
60 KT WILL MAKE ROTATING STORMS POSSIBLE EMBEDDED IN THE HEAVY RAIN.
VAD WIND PROFILES IN ERN MA SHOW VEERED WINDS FROM THE SFC TO 2 KM.
THIS COMBINED WITH LCLS AROUND 600 METERS WILL BE FAVORABLE FOR A
FEW ROTATING STORMS AND THE POTENTIAL FOR AN ISOLATED TORNADO NEAR
THE CIRCULATION CENTER.

..BROYLES.. 08/15/2004

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...GYX...BOX...OKX...ALY...

40407262 40617305 40937347 41317335 41867304 42537226
42807181 43107076 43016975 42186933 41536964 40467136
40307207

Nearby

Mesoscale Discussions in Massachusetts, 2004Mesoscale Discussions in Connecticut, 2004Mesoscale Discussions in Rhode Island, 2004Every mesoscale discussion in 2004

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.