the northeast convective flash flood project: july 29 th 2009 flash flood case study
DESCRIPTION
The Northeast Convective Flash Flood Project: July 29 th 2009 Flash Flood Case Study. Derek V. Mallia University at Albany Department of Atmospheric and Environmental Sciences Synoptic Meteorology Presentation. Outline:. Synopsis of case Overview of Synoptic/ Mesoscale Features - PowerPoint PPT PresentationTRANSCRIPT
The Northeast Convective Flash Flood Project:
July 29th 2009 Flash Flood Case Study
Derek V. Mallia University at AlbanyDepartment of Atmospheric and Environmental SciencesSynoptic Meteorology Presentation
Outline:Synopsis of caseOverview of Synoptic/Mesoscale
FeaturesAnalysis of indicesConclusion
Data Sources Used:Advanced Weather Information Processing System
(AWIPS)Weather Event Simulator (WES)Rapid Update Cycle (RUC40) (RUC80)Albany Radar (KENX)Geostationary Operational Environmental Satellite
(GOES)
Synopsis of July 29 2009 Flash Flood Event• Widespread flash flood event• Occurred in:
Saratoga County Greene County Rensselaer County Columbia County Berkshire County
• One day event• Occurred between 17-01 UTC
• Frontal case• Associated with cold front
over Ontario Lake
Pictures from July 29th Event
Courtesy of Brian Frugis and Tim Scrom
Courtesy of Stefan Bagnato
WV Satellite and 500 hPa RUC 80 Height Loop
RUC 80 500hPa Height Analysis16 UTC
RUC 40 500hPa Height and Relative Vorticity
16 UTC 20 UTCUpstream Vorticity Maximums
Upstream Vorticity Maximums
RUC 40 250hPa Wind Analysis 16 UTC
RUC 40 250hPa Wind Analysis 20 UTC
RUC 40 250hPa Wind Analysis 00 UTC
RUC 40 250hPa Wind Divergence Analysis16 UTC
20 UTCRUC 40 250hPa Wind Divergence Analysis
RUC 40 PWAT & 850 hPa Wind and Theta-E Advection
16 UTC16 UTC
20 UTC
RUC 40 PWAT & 850 hPa Wind and Theta-E Advection
RUC 40 PWAT & 850 hPa Wind and Theta-E Advection
00 UTC
KENX Radar Image Loops 16:27-22:24 UTC
KENX Radar Image Loops 22:24-00 UTC
Surface Analysis 18 UTC
Surface Analysis 20 UTC
Sounding Derived Parameters
CAPE= 2614J/kg “tall and moderate CAPE”
K-Index= 32Total Totals= 47PWAT= 1.86 in.Freezing level= 13.9k ftDew point= lower 70s FMax low level wind= 30 kts; southwest
Conclusions:Dual vorticity and right entrance region of jet
provided favorable upper air dynamics
Baroclinic boundary provided focus for precipitation due to isentropic lift.
Plenty of moisture transport into region
High CAPE and moderate K-Index value suggest plenty of instability
Possible topographic effects?
AcknowledgementsJoe Villani; Albany National Weather Service Neil Stuart; Albany National Weather Service Julie Gabriel; University of DelawareAllen Srock; University at AlbanyNick Metz; University at AlbanyAnd the rest of the NWS staff!