Reduced Rainfall in Future Heavy Precipitation Events Related to Contracted Rain Area Despite Increased Rain Rate

Abstract The quantitative precipitation estimate (QPE) algorithm developed and described in Part I was validated using data collected from 33 Weather Surveillance Radar 1988-Doppler (WSR-88D) radars on 37 calendar days east of the Rocky Mountains. A key physical parameter to the algorithm is the parameter alpha α, defined as the ratio of specific attenuation A to specific differential phase KDP. Examination of a significant sample of tropical and continental precipitation events indicated that α was sensitive to changes in drop size distribution and exhibited lower (higher) values when there were lower (higher) concentrations of larger (smaller) rain drops. As part of the performance assessment, the prototype algorithm generated QPEs utilizing a real-time estimated and a fixed α were created and evaluated. The results clearly indicated ~26% lower errors and a 26% better bias ratio with the QPE utilizing a real-time estimated α as opposed to using a fixed value as was done in previous studies. Comparisons between the QPE utilizing a real-time estimated α and the operational dual-polarization (dual-pol) QPE used on the WSR-88D radar network showed the former exhibited ~22% lower errors, 7% less bias, and 5% higher correlation coefficient when compared to quality controlled gauge totals. The new QPE also provided much better estimates for moderate to heavy precipitation events and performed better in regions of partial beam blockage than the operational dual-pol QPE.

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Changes in Intense Precipitation over the Central United States

Journal of Hydrometeorology ◽

10.1175/jhm-d-11-039.1 ◽

2012 ◽

Vol 13 (1) ◽

pp. 47-66 ◽

Cited By ~ 137

Author(s):

Pavel Ya. Groisman ◽

Richard W. Knight ◽

Thomas R. Karl

Keyword(s):

United States ◽

Extreme Precipitation ◽

Heavy Precipitation ◽

The Past ◽

Extreme Precipitation Events ◽

Intense Precipitation ◽

Central United States ◽

Extreme Rain ◽

Rain Events ◽

Precipitation Events

Abstract In examining intense precipitation over the central United States, the authors consider only days with precipitation when the daily total is above 12.7 mm and focus only on these days and multiday events constructed from such consecutive precipitation days. Analyses show that over the central United States, a statistically significant redistribution in the spectra of intense precipitation days/events during the past decades has occurred. Moderately heavy precipitation events (within a 12.7–25.4 mm day−1 range) became less frequent compared to days and events with precipitation totals above 25.4 mm. During the past 31 yr (compared to the 1948–78 period), significant increases occurred in the frequency of “very heavy” (the daily rain events above 76.2 mm) and extreme precipitation events (defined as daily and multiday rain events with totals above 154.9 mm or 6 in.), with up to 40% increases in the frequency of days and multiday extreme rain events. Tropical cyclones associated with extreme precipitation do not significantly contribute to the changes reported in this study. With time, the internal precipitation structure (e.g., mean and maximum hourly precipitation rates within each preselected range of daily or multiday event totals) did not noticeably change. Several possible causes of observed changes in intense precipitation over the central United States are discussed and/or tested.

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Perturbing the potential vorticity field in mesoscale forecasts of two Mediterranean heavy precipitation events

Tellus A Dynamic Meteorology and Oceanography ◽

10.3402/tellusa.v64i0.17224 ◽

2012 ◽

Vol 64 (1) ◽

pp. 17224 ◽

Cited By ~ 3

Author(s):

Maria-Del-Mar Vich ◽

Romualdo Romero ◽

Evelyne Richard ◽

Philippe Arbogast ◽

Karine Maynard

Keyword(s):

Potential Vorticity ◽

Heavy Precipitation ◽

Vorticity Field ◽

Precipitation Events

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Atmospheric conditions associated with heavy precipitation events in comparison to seasonal means in the western mediterranean region

Climate Dynamics ◽

10.1007/s00382-016-3058-y ◽

2016 ◽

Vol 51 (3) ◽

pp. 951-967 ◽

Cited By ~ 15

Author(s):

Samiro Khodayar ◽

Norbert Kalthoff ◽

Christoph Kottmeier

Keyword(s):

Mediterranean Region ◽

Heavy Precipitation ◽

Western Mediterranean ◽

Atmospheric Conditions ◽

Precipitation Events

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Changes in Temperature and Precipitation Extremes in Superparameterized CAM in Response to Warmer SSTs

Journal of Climate ◽

10.1175/jcli-d-17-0214.1 ◽

2017 ◽

Vol 30 (24) ◽

pp. 9827-9845 ◽

Cited By ~ 6

Author(s):

Xin Zhou ◽

Marat F. Khairoutdinov

Keyword(s):

Large Scale ◽

Rain Rate ◽

Precipitable Water ◽

Heavy Precipitation ◽

Global Scale ◽

Precipitation Extremes ◽

Temperature And Precipitation ◽

Hourly Data ◽

Cloud Resolving Model ◽

Cold Extremes

Subdaily temperature and precipitation extremes in response to warmer SSTs are investigated on a global scale using the superparameterized (SP) Community Atmosphere Model (CAM), in which a cloud-resolving model is embedded in each CAM grid column to simulate convection explicitly. Two 10-yr simulations have been performed using present climatological sea surface temperature (SST) and perturbed SST climatology derived from the representative concentration pathway 8.5 (RCP8.5) scenario. Compared with the conventional CAM, SP-CAM simulates colder temperatures and more realistic intensity distribution of precipitation, especially for heavy precipitation. The temperature and precipitation extremes have been defined by the 99th percentile of the 3-hourly data. For temperature, the changes in the warm and cold extremes are generally consistent between CAM and SP-CAM, with larger changes in warm extremes at low latitudes and larger changes in cold extremes at mid-to-high latitudes. For precipitation, CAM predicts a uniform increase of frequency of precipitation extremes regardless of the rain rate, while SP-CAM predicts a monotonic increase of frequency with increasing rain rate and larger change of intensity for heavier precipitation. The changes in 3-hourly and daily temperature extremes are found to be similar; however, the 3-hourly precipitation extremes have a significantly larger change than daily extremes. The Clausius–Clapeyron scaling is found to be a relatively good predictor of zonally averaged changes in precipitation extremes over midlatitudes but not as good over the tropics and subtropics. The changes in precipitable water and large-scale vertical velocity are equally important to explain the changes in precipitation extremes.

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Listening to Stakeholders: Initiating Research on Sub-seasonal to Seasonal Heavy Precipitation Events in the Contiguous U.S. by First Understanding What Stakeholders Need

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-20-0313.1 ◽

2021 ◽

pp. 1-35

Author(s):

Olivia VanBuskirk ◽

Paulina Ćwik ◽

Renee A. McPherson ◽

Heather Lazrus ◽

Elinor Martin ◽

...

Keyword(s):

United States ◽

Environmental Management ◽

Predictive Models ◽

Extreme Precipitation ◽

Heavy Precipitation ◽

Role Playing ◽

Extreme Precipitation Events ◽

Rainfall Extremes ◽

Actionable Science ◽

Precipitation Events

AbstractHeavy precipitation events and their associated flooding can have major impacts on communities and stakeholders. There is a lack of knowledge, however, about how stakeholders make decisions at the sub-seasonal to seasonal (S2S) timescales (i.e., two weeks to three months). To understand how decisions are made and S2S predictions are or can be used, the project team for “Prediction of Rainfall Extremes at Sub-seasonal to Seasonal Periods” (PRES2iP) conducted a two-day workshop in Norman, Oklahoma, during July 2018. The workshop engaged 21 professionals from environmental management and public safety communities across the contiguous United States in activities to understand their needs for S2S predictions of potential extended heavy precipitation events. Discussions and role-playing activities aimed to identify how workshop participants manage uncertainty and define extreme precipitation, the timescales over which they make key decisions, and the types of products they use currently. This collaboration with stakeholders has been an integral part of PRES2iP research and has aimed to foster actionable science. The PRES2iP team is using the information produced from this workshop to inform the development of predictive models for extended heavy precipitation events and to collaboratively design new forecast products with our stakeholders, empowering them to make more-informed decisions about potential extreme precipitation events.

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On the Relationship between Intensity and Rainfall Distribution in Tropical Cyclones Making Landfall over China

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-16-0334.1 ◽

2017 ◽

Vol 56 (10) ◽

pp. 2883-2901 ◽

Cited By ~ 26

Author(s):

Zifeng Yu ◽

Yuqing Wang ◽

Haiming Xu ◽

Noel Davidson ◽

Yandie Chen ◽

...

Keyword(s):

Tropical Cyclones ◽

Rain Rate ◽

Vertical Wind Shear ◽

Intensity Change ◽

Total Rainfall ◽

Rainfall Distribution ◽

Rain Area ◽

Maximum Rainfall ◽

Rain Rates ◽

The Relationship

AbstractTRMM satellite 3B42 rainfall estimates for 133 landfalling tropical cyclones (TCs) over China during 2001–15 are used to examine the relationship between TC intensity and rainfall distribution. The rain rate of each TC is decomposed into axisymmetric and asymmetric components. The results reveal that, on average, axisymmetric rainfall is closely related to TC intensity. Stronger TCs have higher averaged peak axisymmetric rain rates, more averaged total rain, larger averaged rain areas, higher averaged rain rates, higher averaged amplitudes of the axisymmetric rainfall, and lower amplitudes of wavenumbers 1–4 relative to the total rainfall. Among different TC intensity change categories, rapidly decaying TCs show the most rapid decrease in both the total rainfall and the axisymmetric rainfall relative to the total rain. However, the maximum total rain, maximum rain area, and maximum rain rate are not absolutely dependent on TC intensity, suggesting that stronger TCs do not have systematically higher maximum rain rates than weaker storms. Results also show that the translational speed of TCs has little effect on the asymmetric rainfall distribution in landfalling TCs. The maximum rainfall of both the weaker and stronger TCs is generally located downshear to downshear left. However, when environmental vertical wind shear (VWS) is less than 5 m s−1, the asymmetric rainfall maxima are more frequently located upshear and onshore, suggesting that in weak VWS environments the coastline could have a significant effect on the rainfall asymmetry in landfalling TCs.

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Analysis of intense rainfall events on Madeira Island during the 2009/2010 winter

Natural Hazards and Earth System Science ◽

10.5194/nhess-12-2225-2012 ◽

2012 ◽

Vol 12 (7) ◽

pp. 2225-2240 ◽

Cited By ~ 26

Author(s):

F. T. Couto ◽

R. Salgado ◽

M. J. Costa

Keyword(s):

Precipitable Water ◽

Heavy Precipitation ◽

Rain Gauge ◽

Horizontal Resolution ◽

Pressure System ◽

Orographic Effects ◽

Madeira Island ◽

High Rainfall ◽

High Precipitation Events ◽

Precipitation Events

Abstract. This paper constitutes a step towards the understanding of some characteristics associated with high rainfall amounts and flooding on Madeira Island. The high precipitation events that occurred during the winter of 2009/2010 have been considered with three main goals: to analyze the main atmospheric characteristics associated with the events; to expand the understanding of the interaction between the island and the atmospheric circulations, mainly the effects of the island on the generation or intensification of orographic precipitation; and to evaluate the performance of high resolution numerical modeling in simulating and forecasting heavy precipitation events over the island. The MESO-NH model with a horizontal resolution of 1 km is used, as well as rain gauge data, synoptic charts and measurements of precipitable water obtained from the Atmospheric InfraRed Sounder (AIRS). The results confirm the influence of the orographic effects on precipitation over Madeira as well as the tropical–extratropical interaction, since atmospheric rivers were detected in six out of the seven cases analyzed, acting as a low level moisture supplier, which together with the orographic lifting induced the high rainfall amounts. Only in one of the cases the presence of a low pressure system was identified over the archipelago.

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