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temperature anomalies, as stratospheric temperature conditions are primarily of opposite sign to those in the troposphere for the duration of each episode. That these stratospheric warmings and coolings precede their tropospheric counterparts is consistent with the tilt of blocked baroclinic waves with height ( Palmen and Newton 1969 ). The hourly winter NetLW time series at the SHEBA surface site (upper panel, Fig. 2 ) ranges between −65 and 20 W m −2 over the course of the winter 1997/98 season
temperature anomalies, as stratospheric temperature conditions are primarily of opposite sign to those in the troposphere for the duration of each episode. That these stratospheric warmings and coolings precede their tropospheric counterparts is consistent with the tilt of blocked baroclinic waves with height ( Palmen and Newton 1969 ). The hourly winter NetLW time series at the SHEBA surface site (upper panel, Fig. 2 ) ranges between −65 and 20 W m −2 over the course of the winter 1997/98 season
with AR days in the high elevation regions of the Cascades, Olympic Peninsula, and Sierra Nevada ( Fig. 5c ) are similar to the 40%–60% of snowfall in the western United States attributed to ARs by Rutz et al. (2014 ; their Fig. 8b) and the 60%–80% frequencies of winter weather–related WWAs associated with ARs in California by Cordeira et al. (2018) . The 50%–90% frequency of wind-related WWAs days that occurred in association with cool-season AR days in the Pacific Northwest and Pacific Central
with AR days in the high elevation regions of the Cascades, Olympic Peninsula, and Sierra Nevada ( Fig. 5c ) are similar to the 40%–60% of snowfall in the western United States attributed to ARs by Rutz et al. (2014 ; their Fig. 8b) and the 60%–80% frequencies of winter weather–related WWAs associated with ARs in California by Cordeira et al. (2018) . The 50%–90% frequency of wind-related WWAs days that occurred in association with cool-season AR days in the Pacific Northwest and Pacific Central
differentiate between GSLE and non-GSLE periods, through the development and analysis of a 13-yr cool-season radar-derived climatology. We will show that GSLE events occur primarily within specific ranges of instability, moisture, and kinematic parameters, whereas considerable overlap exists between the conditions associated with different GSLE morphologies. Furthermore, we identify deficiencies in current forecast techniques and present a new probabilistic approach using lake–air temperature difference
differentiate between GSLE and non-GSLE periods, through the development and analysis of a 13-yr cool-season radar-derived climatology. We will show that GSLE events occur primarily within specific ranges of instability, moisture, and kinematic parameters, whereas considerable overlap exists between the conditions associated with different GSLE morphologies. Furthermore, we identify deficiencies in current forecast techniques and present a new probabilistic approach using lake–air temperature difference
soundings (e.g., vertical velocity) at grid points close to KSLC. The NARR was also used for filling in any missing observations in the soundings. Both reanalysis datasets were obtained from the National Oceanic and Atmospheric Administration/Office of Oceanic and Atmospheric Research/Earth System Research Laboratory’s (NOAA/OAR/ESRL) Physical Science Division (information online at http://www.cdc.noaa.gov ). b. Inversion definition During each winter season, Salt Lake City is subjected to two main
soundings (e.g., vertical velocity) at grid points close to KSLC. The NARR was also used for filling in any missing observations in the soundings. Both reanalysis datasets were obtained from the National Oceanic and Atmospheric Administration/Office of Oceanic and Atmospheric Research/Earth System Research Laboratory’s (NOAA/OAR/ESRL) Physical Science Division (information online at http://www.cdc.noaa.gov ). b. Inversion definition During each winter season, Salt Lake City is subjected to two main
separately. Table 1. Index phase for the highest-frequency storm seasons (top 15%). All climate indices have been normalized to Z scores (anomaly/ σ ). Negative values (<0.5 σ ) are italicized and positive values (>0.5 σ ) are boldface. 1) ETL Because ETL events are infrequent in late winter (August) we restrict the seasonal investigation to May–June–July. The six highest-frequency ETL seasons (top 15%) were 1984, 1985, 1990, 1996, 1999, and 2008. Seasonal ETL frequency is correlated to cool SST in
separately. Table 1. Index phase for the highest-frequency storm seasons (top 15%). All climate indices have been normalized to Z scores (anomaly/ σ ). Negative values (<0.5 σ ) are italicized and positive values (>0.5 σ ) are boldface. 1) ETL Because ETL events are infrequent in late winter (August) we restrict the seasonal investigation to May–June–July. The six highest-frequency ETL seasons (top 15%) were 1984, 1985, 1990, 1996, 1999, and 2008. Seasonal ETL frequency is correlated to cool SST in
wind velocities were first averaged into a daily mean, from which the daily wind speeds were evaluated. The daily mean wind speeds from the model and the observations were then averaged in the same manner to produce their monthly means. During the 2003/04 cold season, month-to-month changes in surface winds based on the JRA-25 analysis are characterized by the rapid maturing of the East Asian winter monsoon in December and its subsequent gradual weakening in late winter and early spring ( Fig. 1
wind velocities were first averaged into a daily mean, from which the daily wind speeds were evaluated. The daily mean wind speeds from the model and the observations were then averaged in the same manner to produce their monthly means. During the 2003/04 cold season, month-to-month changes in surface winds based on the JRA-25 analysis are characterized by the rapid maturing of the East Asian winter monsoon in December and its subsequent gradual weakening in late winter and early spring ( Fig. 1
UHI environment may act as a lake-enhanced snowfall environment, and possibly enhance urban snowfall downwind of the city center, is presented. Urban temperatures have been shown to exceed rural temperatures in all seasons, including winter ( Gallo and Owen 1999 ; Seeley and Jensen 2006 ). The distribution of the urban temperature through the vertical profile of the atmosphere over the UHI is comparable to that over an unfrozen lake ( Dixon and Mote 2003 ; Tardy 2000 ). When determining the
UHI environment may act as a lake-enhanced snowfall environment, and possibly enhance urban snowfall downwind of the city center, is presented. Urban temperatures have been shown to exceed rural temperatures in all seasons, including winter ( Gallo and Owen 1999 ; Seeley and Jensen 2006 ). The distribution of the urban temperature through the vertical profile of the atmosphere over the UHI is comparable to that over an unfrozen lake ( Dixon and Mote 2003 ; Tardy 2000 ). When determining the
1. Introduction Cool-season long-lived and widespread extreme precipitation events often lead to substantial societal and economic impacts, including the loss of life, property, and infrastructure. One example is the multiple storms composing the historic ice storm of January 1998, which affected parts of northern New York (NY), northern New England, eastern Ontario, and southern Quebec with up to 100 mm of ice accumulation (along with flooding farther south), leading to millions of power
1. Introduction Cool-season long-lived and widespread extreme precipitation events often lead to substantial societal and economic impacts, including the loss of life, property, and infrastructure. One example is the multiple storms composing the historic ice storm of January 1998, which affected parts of northern New York (NY), northern New England, eastern Ontario, and southern Quebec with up to 100 mm of ice accumulation (along with flooding farther south), leading to millions of power
Reanalysis (NARR). The annual cycle of precipitation in the Caribbean and Central American region has a rainy season in boreal summer ( Giannini et al. 2000 ; Taylor et al. 2002 ) that extends from May through October. During boreal summer the intertropical convergence zone (ITCZ) shifts northward, leading to intense precipitation over the tropical North Atlantic, Central America, and the tropical northeastern Pacific. However, over the Caribbean Sea the precipitation is not as intense as it is over
Reanalysis (NARR). The annual cycle of precipitation in the Caribbean and Central American region has a rainy season in boreal summer ( Giannini et al. 2000 ; Taylor et al. 2002 ) that extends from May through October. During boreal summer the intertropical convergence zone (ITCZ) shifts northward, leading to intense precipitation over the tropical North Atlantic, Central America, and the tropical northeastern Pacific. However, over the Caribbean Sea the precipitation is not as intense as it is over
most frequently associated with CO deaths, and that most nonfire CO fatalities occurred in the cool-season months. Other research reveals that fatal CO cases disproportionately impact non-Hispanic White individuals after weather perils ( Black 2015 )—for example, 73% of CO fatalities linked to Hurricane Irma ( Issa et al. 2018 ), as well as all CO deaths connected to the four major hurricanes of 2004 (Charley, Frances, Ivan, and Jeanne), were non-Hispanic White ( CDC 2005a ; Hampson and Stock
most frequently associated with CO deaths, and that most nonfire CO fatalities occurred in the cool-season months. Other research reveals that fatal CO cases disproportionately impact non-Hispanic White individuals after weather perils ( Black 2015 )—for example, 73% of CO fatalities linked to Hurricane Irma ( Issa et al. 2018 ), as well as all CO deaths connected to the four major hurricanes of 2004 (Charley, Frances, Ivan, and Jeanne), were non-Hispanic White ( CDC 2005a ; Hampson and Stock
