Document: NUREG-0800
Document ID: cd6f87fe-98e4-4726-8a49-7793f2f2caf1
Document Type: srp
Title: REGIONAL CLIMATOLOGY
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070225.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.3.1
CFR Part: 
CFR Title: 

Content:
REVIEW RESPONSIBILITIES Primary - Accident Evaluation Branch (AEB) Emergency Preparedness and Radiation Protection Branch (PERB)1 Secondary - None I. AREAS OF REVIEW Information for a construction permit (CP), operating license (OL), combined license (COL), standard design certification, or early site permit is presented by the applicant and reviewed by 2 the staff concerning averages and extremes of climatic conditions and regional meteorological phenomena which affect the safe design and siting of the plant. The review covers the following specific areas: 1. A description of the general climate of the region with respect to types of air masses, synoptic features (high- and low-pressure systems and frontal systems), general airflow patterns (wind direction and speed), temperature and humidity, precipitation (rain, snow, and sleet), and relationships between synoptic-scale atmospheric processes and local (site) meteorological conditions. 2. Seasonal and annual frequencies of severe weather phenomena, including tornadoes, waterspouts, thunderstorms, lightning, hail (including probable maximum size), and high air pollution potential. 3. Meteorological conditions used as design and operating bases, including: DRAFT Rev. 3 - April 1996 2.3.1-2 a. The maximum snow and ice load (water equivalent) that the roofs of safety-related structures must be capable of withstanding during plant operation. b. Ultimate heat sink meteorological conditions resulting in maximum evaporation and drift loss of water and minimum water cooling. c. Tornado parameters, including translational speed, rotational speed, and the maximum pressure differential with the associated time interval. d. Hundred-year return period "fastest mile of wind," including vertical velocity distribution and gust factor. e. Probable maximum annual frequency of occurrence and time duration of freezing rain (ice storms) and, where applicable, dust (sand) storms. f. Maximum rainfall rate.3 g. Other meteorological and