Search Results
and 1700 MST 11 May soundings. As the jet region north of Utah moved farther to the south during the second half of the night, northern Utah came under the influence of a southwesterly flow ( Fig. 3 ). Fig . 3. ERA-Interim reanalysis ( Dee et al. 2011 ) of 850-hPa geopotential height (black solid lines; 50-m contour interval), temperature (white dashed lines; 2-K contour interval), wind (arrows), and relative humidity (color contours). The red symbol indicates the location of Granite Mountain, and
and 1700 MST 11 May soundings. As the jet region north of Utah moved farther to the south during the second half of the night, northern Utah came under the influence of a southwesterly flow ( Fig. 3 ). Fig . 3. ERA-Interim reanalysis ( Dee et al. 2011 ) of 850-hPa geopotential height (black solid lines; 50-m contour interval), temperature (white dashed lines; 2-K contour interval), wind (arrows), and relative humidity (color contours). The red symbol indicates the location of Granite Mountain, and
Forecasting Model (WRF). In particular, version 3.3 of an Advanced Research version of the WRF (ARW; Skamarock et al. 2008 ) is used for three typical severe weather events (i.e., a low-level jet, a cold front, and a wintertime persistent inversion) over the southern Great Plains (SGP) and the Intermountain West of the United States. Our purposes are not only to examine the ability of the ARW to predict near-surface atmospheric conditions, but also to compare the predictability of near-surface conditions
Forecasting Model (WRF). In particular, version 3.3 of an Advanced Research version of the WRF (ARW; Skamarock et al. 2008 ) is used for three typical severe weather events (i.e., a low-level jet, a cold front, and a wintertime persistent inversion) over the southern Great Plains (SGP) and the Intermountain West of the United States. Our purposes are not only to examine the ability of the ARW to predict near-surface atmospheric conditions, but also to compare the predictability of near-surface conditions
(big and small) gaps. Figure 8 shows the measured vertical structure of fully established nocturnal downvalley flow in the basins, where a low-level jet is evident. The IOS-Sagebrush exhibits much cooler surface temperatures and a strong low-level elevated capping inversion that prevents the surface jet from mixing vertically. The larger ground heat flux at IOS-Playa leads to warmer nighttime surface temperatures than at Sagebrush, allowing the nocturnal jet to mix deeper aloft. F ig . 8. (bottom
(big and small) gaps. Figure 8 shows the measured vertical structure of fully established nocturnal downvalley flow in the basins, where a low-level jet is evident. The IOS-Sagebrush exhibits much cooler surface temperatures and a strong low-level elevated capping inversion that prevents the surface jet from mixing vertically. The larger ground heat flux at IOS-Playa leads to warmer nighttime surface temperatures than at Sagebrush, allowing the nocturnal jet to mix deeper aloft. F ig . 8. (bottom
gradient over the top of the tower (orange) and the bottom of the tower (blue). Sample size for all variables is 43 LTFs. Prior to the initiation of the LTF, the flow field ( Fig. 5b ) and stability ( Fig. 5c ) at ES2 indicate the presence of a katabatic flow. The wind is out of the west (downslope), with a jet structure with a peak observed wind speed of 4 m. Relatively strong near-surface stratification of 1°C m −1 is also observed ( Fig. 5c ). These flow characteristics are indicative of katabatic
gradient over the top of the tower (orange) and the bottom of the tower (blue). Sample size for all variables is 43 LTFs. Prior to the initiation of the LTF, the flow field ( Fig. 5b ) and stability ( Fig. 5c ) at ES2 indicate the presence of a katabatic flow. The wind is out of the west (downslope), with a jet structure with a peak observed wind speed of 4 m. Relatively strong near-surface stratification of 1°C m −1 is also observed ( Fig. 5c ). These flow characteristics are indicative of katabatic
, 2008 : A description of the Advanced Research WRF version 3. NCAR Tech. Note NCAR/TN-475+STR, 113 pp., doi: 10.5065/D68S4MVH . 10.5065/D68S4MVH Tenenbaum , J. , 1996 : Jet stream winds: Comparisons of aircraft observations with analyses . Wea. Forecasting , 11 , 188 – 197 , doi: 10.1175/1520-0434(1996)011<0188:JSWCOA>2.0.CO;2 . 10.1175/1520-0434(1996)011<0188:JSWCOA>2.0.CO;2 Wang , J. , H. L. Cole , D. J. Carlson , E. R. Miller , K. Beierle , A. Paukkunen , and T. K. Laine
, 2008 : A description of the Advanced Research WRF version 3. NCAR Tech. Note NCAR/TN-475+STR, 113 pp., doi: 10.5065/D68S4MVH . 10.5065/D68S4MVH Tenenbaum , J. , 1996 : Jet stream winds: Comparisons of aircraft observations with analyses . Wea. Forecasting , 11 , 188 – 197 , doi: 10.1175/1520-0434(1996)011<0188:JSWCOA>2.0.CO;2 . 10.1175/1520-0434(1996)011<0188:JSWCOA>2.0.CO;2 Wang , J. , H. L. Cole , D. J. Carlson , E. R. Miller , K. Beierle , A. Paukkunen , and T. K. Laine
