Jennifer Q. BelgeEric G. HoffmanPlymouth State University11/06/08Northeast Regional Operational WorkshopPreferred Regions of Convective Development over Northern New England as a Function of Flow Regime: Southwesterly Flow Case Studieshttp://www.eoearth.org/upload/thumb/6/61/Mature_thunderstorm_cloud.jpg/250px-Mature_thunderstorm_cloud.jpg

Previous Work- Evan Lowery (2008)5 year climatology of northern New England thunderstormsKGYX radar domainApril September2003-2007SCITSpatial distribution of cells as a function of large-scale flow at 700 hPa

Results- Lowery (2008)SW FLOW5 clustersCentral Oxford, Franklin and Somerset counties in MEJust south of Belknap, Merrimack border in NHSouthern Oxford county in MENorthern Grafton county in NHSouthern Somerset county in MEGraftonOxfordFranklinSomersetCoosCarrollBelknapMerrimackYorkStraffordRockinghamHillsboroughSullivanCheshirePiscataquisAroostookCumberlandAndroscogginKennebecPenobscotWaldoKnoxLincolnSagadahocNW FLOW3 clustersBorder of Strafford (NH) and York (ME) countiesTri-county border of Oxford (ME), Carroll (NH) and York(ME)Border of Grafton (NH) and Coos (NH) county

MotivationLowerys study did not address:Why are there preferred regions of development with respect to flow regime?Differences between flow regimes?Forecasting potentialKGYX

Scientific QuestionsWhy do thunderstorm cells initiate where they do as a function of large-scale flow?SW and NW @ 700 hPa onlyAre there certain meteorological patterns present in the mesoscale environment that is conducive to convection in these regions found by Lowery (2008)?

Data and MethodologyCase StudiesRadar reflectivity examined for each case from May-September 2007 onlyCase study selectionCells were to initiate in the significant areas identified by Lowery (2008)Cells were to not be associated with a frontal zoneEliminate influence of frontal boundary in mesoscale analysis

NWFLOW

SWFLOW

ResultsRadarSounding 12 UTCKGYXSurface analysisRUCSynoptic overview12 UTCLAPSKGYXMesoscale analysis17 UTC

July 13, 2007

Synoptic Analysis12 UTC

Surface Analysis 12 UTC

500 hPa Height 12 UTC

250 hPa Height and Wind 12 UTC

Sounding 12 UTC

Mesoscale Analysis17 UTC

Surface Analysis 18 UTC

Surface Dew Point 17 UTC

Surface CAPE 17 UTC

Surface Flow Vectors and Topo 17 UTC

Surface Flow Vectors and Topo 17 UTC

Surface Convergence 17 UTC

Mean Sea Level Pressure 17 UTC

Conclusions

Preliminary ResultsJuly 13, 2007 SW Flow CaseMoisture & instability sufficient over entire areaGenesis region was not uniqueSurface convergence and corresponding surface trough could provide the necessary liftResults from the August 2, 2007 case show the same results and conclusions

WORKS CITED

Lowery, E.M, 2008: Using the WSR-88D Storm Structure Product to Develop a Climatology of Northern New England Thunderstorms as a Function of Large-Scale Flow, Plymouth State University, Master of Science ThesisQuestions?http://www.wetter-vista.de/pub/thunderstorm/cb-big.jpg

Vales in initiation region around 50-55 degrees FTowards the coast- around 60 degrees F*800-1500 (bulls eye) J/kg in and around initiation areaValues of around 1300 J/kg near coast bulls eyes*