Scientific and Technical Aerospace Reports Volume 38 July 28, 2000

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METEOROLOGY AND CLIMATOLOGY
20000062469 ENSCO, Inc., Applied Meteorology Unit, Cocoa Beach, FL USA
Improved Anvil Forecasting Final Report
Lambert, Winifred C., ENSCO, Inc., USA; May 2000; 32p; In English
Contract(s)/Grant(s): NAS10-96018
Report No.(s): NASA/CR-2000-208573; NAS 1.26:208573; Rept-00-002; No Copyright; Avail: CASI; A03, Hardcopy; A01,
Microfiche
This report describes the outcome of Phase 1 of the AMU’s Improved Anvil Forecasting task. Forecasters in the 45th Weather
Squadron and the Spaceflight Meteorology Group have found that anvil forecasting is a difficult task when predicting LCC and
FR violations. The purpose of this task is to determine the technical feasibility of creating an anvil-forecasting tool. Work on this
study was separated into three steps: literature search, forecaster discussions, and determination of technical feasibility. The literature
search revealed no existing anvil-forecasting techniques. However, there appears to be growing interest in anvils in recent
years. If this interest continues to grow, more information will be available to aid in developing a reliable anvil-forecasting tool.
The forecaster discussion step revealed an array of methods on how better forecasting techniques could be developed. The forecasters
have ideas based on sound meteorological principles and personal experience in forecasting and analyzing anvils. Based
on the information gathered in the discussions with the forecasters, the conclusion of this report is that it is technically feasible
at this time to develop an anvil forecasting technique that will significantly contribute to the confidence in anvil forecasts.
Author
Technology Assessment; Feasibility Analysis; Forecasting; Predictions; Computer Systems Simulation
20000063498 NASA Goddard Space Flight Center, Greenbelt, MD USA
Effect of Combined Spaceborne Microwave and Continuous Lightning Measurements on Precipitation Forecasts of the
1998 Ground-Hog Day Storm
Weinman, James A., NASA Goddard Space Flight Center, USA; Chang, Dong-Eon, Universities Space Research Association,
USA; Morales, Carlos A., Connecticut Univ., USA; [2000]; 2p; In English; No Copyright; Avail: CASI; A01, Hardcopy; A01,
Microfiche
We evaluated the impact of several newly available sources of meteorological data on mesoscale model forecasts of precipitation produced
by the extra-tropical cyclone that struck Florida on February 2, 1998. Precipitation distributions of convective rainfall events were
derived from Special Sensor Microwave Imager (SSM/I) and Multi-Channel Passive Microwave Sensor (TMI) microwave radiometric data
by means of the Goddard PROFiling (GPROF) algorithm. Continuous lightning distributions were obtained from sferics measurements
obtained from a network of VLF radio receivers. Histograms of coincident sferics frequency distributions were matched to those of precipitation
to derive bogus convective rainfall rates from the continuously available sferics measurements. SSM/I and TMI microwave data were
used to derive Integrated Precipitable Water (IPW) distributions. The TMI also provided sea surface temperatures (SSTS) of the Loop Current
and Gulf Stream with improved structural detail. A series of experiments assimilated IPW and latent heating from the bogus convective
rainfall for six-hours in the MM5 mesoscale forecast model to produce nine-hour forecasts of all rainfall as well as other weather parameters.
Although continuously assimilating latent heating only slightly improved the surface pressure distribution forecast, it significantly improved
the precipitation forecasts. Correctly locating convective rainfall was found critical for assimilating latent heating in the forecast model, but
measurement of the rainfall intensity proved to be less important. The improved SSTs also had a positive impact on rainfall forecasts for
this case. Assimilating bogus rainfall in the model produced nine-hour forecasts of radar reflectivity distributions that agreed well with coincident
observations from the TRMM spaceborne precipitation radar, ground based radar and spaceborne microwave measurements.
Author
Lightning; Meteorological Radar; Microwave Radiometers; Precipitation (Meteorology); Weather Forecasting; Mesometeorology;
Radar Measurement; Rainstorms
20000063521 ENSCO, Inc., Applied Meteorology Unit, Cocoa Beach, FL USA
IRIS Product Recommendations Final Report
Short, David A., ENSCO, Inc., USA; March 2000; 28p; In English
Contract(s)/Grant(s): NAS10-96018
Report No.(s): NASA/CR-2000-208572; NAS 1.26:208572; Rept-00-001; No Copyright; Avail: CASI; A03, Hardcopy; A01,
Microfiche