224  
FXUS65 KVEF 131804  
AFDVEF  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LAS VEGAS NV  
1105 AM PDT THU AUG 13 2020  
   
SYNOPSIS
 
CONSIDERABLE MID AND HIGH CLOUDS WILL SPREAD UP ACROSS  
THE REGION TODAY. ISOLATED THUNDERSTORMS CAN BE EXPECTED OVER THE  
SOUTHERN SIERRA AND PARTS OF NORTHWEST ARIZONA. MOSTLY SUNNY SKIES  
WILL RETURN FRIDAY AND TEMPERATURES WILL CLIMB WELL ABOVE NORMAL  
LEADING TO EXCESSIVE HEAT THROUGH THE WEEKEND AND MUCH OF NEXT WEEK  
UNDER A STRONG AREA OF HIGH PRESSURE SETTING UP OVER THE WESTERN  
STATES.  
 

 
 
   
UPDATE
 
INCREASED CLOUD COVER HAS ENTERED THE REGION THIS MORNING,  
ENCOMPASSING SOUTHERN NEVADA, SOUTHEASTERN CALIFORNIA AND  
NORTHWESTERN ARIZONA DUE TO ELEVATED MOISTURE FROM THE REMNANTS OF  
ELIDA. ADDITIONALLY, SMOKE LINGERS OVER SOUTHERN NEVADA THIS  
MORNING, WHICH IS A COMBINATION FROM THE LAKE FIRE IN SOCAL AS WELL  
AS A FEW FIRES IN THE NW BAJA. THESE CLOUDS ARE EXPECTED TO MOVE OUT  
OF THE REGION TONIGHT, ALLOWING FOR A SUNNY START TO THE WEEKEND.  
MOISTURE FROM FORMER HURRICANE ELIDA WILL NOT ONLY BRING AN INCREASE  
IN CLOUD COVER, BUT THE CHANCE FOR SOME LIGHT SHOWERS IN THE HIGHER  
ELEVATIONS, PARTICULARLY OVER THE SIERRA AND CENTRAL MOHAVE COUNTY  
THIS AFTERNOON. AN ISOLATED LIGHTNING STRIKE IS NOT OUT OF THE  
QUESTION, WHICH COULD ELEVATE FIRE DANGER CONCERNS. THOUGH SHOWERS  
ARE POSSIBLE, DUE TO THE DRY LOW LEVELS, NOT MUCH IN THE WAY OF  
MEASURABLE RAINFALL IS EXPECTED.  
 
I INCREASED THE CHANCE OF PRECIPITATION IN SAN BERNARDINO COUNTY,  
THE EASTERN SIERRA, AND CENTRAL MOHAVE COUNTY FOR THIS AFTERNOON  
WITH THIS MORNING UPDATE. THE REST OF THE FORECAST LOOKS TO BE IN  
GOOD SHAPE; NO ADDITIONAL CHANGES WERE MADE.  
 
NO UPDATES HAVE BEEN MADE TO THE CURRENT EXCESSIVE HEAT WARNINGS NOR  
HEAT ADVISORIES IN EFFECT, BUT WILL REVISIT THE POSSIBILITY OF AN  
EXPANSION TO ESMERALDA AND SOUTHERN NYE COUNTIES AS WELL AS NORTHERN  
MOHAVE COUNTY. DUE TO THE LONG-DURATION NATURE OF THIS HEAT WAVE,  
EXPECTING TO DIVE FURTHER INTO CONVERSATION WITH NEIGHBORING OFFICES  
REGARDING EXTENDING THESE HEAT HEADLINES THROUGH AT LEAST THE MIDDLE  
OF NEXT WEEK.  
 

 
   
PREVIOUS DISCUSSION
 
320 AM PDT THU AUG 13 2020/  
 
   
SHORT TERM
 
TODAY THROUGH FRIDAY.  
 
CONSIDERABLE CLOUD COVER TODAY THROUGH THIS EVENING WILL BE THE MOST  
NOTABLE CHANGE IN THE WEATHER AS MID AND HIGH LEVEL MOISTURE IS  
PULLED UP ACROSS OUR REGION FROM POST-TROPICAL CYCLONE ELIDA...  
WHICH WAS DISSIPATED WELL WEST OF BAJA CALIFORNIA. THE CHANCE OF ANY  
MEASURABLE PRECIPITATION WILL BE LESS THAN 10 PERCENT ACROSS MOST OF  
THE REGION. THE EXCEPTIONS WILL BE THE SOUTHERN SIERRA AND OWENS  
VALLEY AND ALSO OVER EASTERN MOHAVE COUNTY WHERE SUFFICIENT MOISTURE  
AND INSTABILITY WILL SUPPORT ISOLATED THUNDERSTORMS THIS AFTERNOON.  
 
SKIES WILL CLEAR TONIGHT AS THE SWATH OF MOISTURE LIFTS AWAY TO THE  
NORTH ALLOWING MOSTLY SUNNY SKIES TO RETURN FRIDAY AS HIGH PRESSURE  
OVER ARIZONA AND NEW MEXICO BEGINS TO EXPAND AND STRENGTHEN OVER  
SOUTHERN NEVADA. TEMPERATURES WILL CLIMB 4-5 DEGREES FRIDAY AND THIS  
BEGINS A PROLONGED PERIOD OF WELL ABOVE NORMAL TEMPERATURES  
APPROACHING RECORD VALUES. THE EXCESSIVE HEAT WARNING WHICH GOES  
INTO EFFECT FRIDAY REMAINS UNCHANGED.  

 
   
LONG TERM
 
SATURDAY THROUGH WEDNESDAY.  
 
GEFS ALONG WITH THE ECMWF ENSEMBLE GUIDANCE REMAINS CONSISTENT  
ADVERTISING THAT A STRONG AREA OF HIGH PRESSURE WILL STAY POSITIONED  
OVER THE REGION THIS WEEKEND THROUGH MOST OF NEXT WEEK. THIS WILL  
LEAD TO A PROLONGED HEATWAVE WITH DAILY RECORD HIGHS, AS WELL AS  
HIGH MINIMUM TEMPERATURES POTENTIALLY BEING TIED OR BROKEN. FOR LAS  
VEGAS, WE COULD POTENTIALLY SEE UP TO 6 DAYS WITH HIGH TEMPERATURES  
GREATER OR EQUAL TO 110 DEGREES. THE CURRENT RECORD STRETCH OF DAYS  
FOR AUGUST IS 7 DAYS (8/7/1940-8/13/1940). WE HAVE HAD 6 TIMES WERE  
THE LENGTH OF DAYS WAS EITHER 5 OR 6. RECORDS FOR LAS VEGAS DATE  
BACK TO 1937. THE EXCESSIVE HEAT WARNING RUNS THROUGH MONDAY BUT  
WILL LIKELY NEED TO BE EXTENDED BASED ON HEATRISK VALUES WHICH KEEP  
MOST OF THE AREA IN HIGH-VERY HIGH RISK.  
 
AS FAR AS ANY PRECIPITATION. OPERATIONAL ECMWF CONTINUES TO INDICATE  
THAT SOME MID-LEVEL MOISTURE WILL BECOME TRAPPED AND CIRCULATE  
UNDERNEATH THE STRONG HIGH CENTER. HOWEVER, NOT OVERLY IMPRESSED BY  
THE AMOUNT OF INSTABILITY AS LOW LEVELS REMAIN DRY WITH LITTLE  
PENETRATION OF H85 DEWPOINTS IN EXCESS OF 8 DEGREE C NORTHWARD INTO  
THE MOJAVE DESERT OR SOUTHERN GREAT BASIN. GEFS LOOKS MODESTLY MORE  
AGGRESSIVE WHICH DOES GENERATE AT LEAST A SLIGHT CHANCE OF  
THUNDERSTORMS OVER SOME OF OUR HIGHER TERRAIN EACH AFTERNOON AND  
EVENING. THESE STORMS WOULD PRODUCE MORE WIND AND LIGHTNING THAN  
RAIN SO NEW FIRE STARTS ARE A CONCERN AS WELL.  
 

 
   
AVIATION...FOR MCCARRAN
 
BY EARLY THIS AFTERNOON, WINDS WILL  
SHIFT TO THE SOUTHWEST AT SPEEDS OF AROUND 9-12 KNOTS WITH  
INTERMITTENT GUSTS OF 15-20 KNOTS POSSIBLE. THERE ARE LOW-END  
CHANCES FOR A STRAY SHOWER OR STORM TO DEVELOP OVER THE HIGHER  
ELEVATIONS OF CLARK COUNTY BETWEEN 20Z-01Z WHICH COULD PUSH SOME  
GUSTY, OUTFLOW WINDS INTO THE VALLEY LATER THIS AFTERNOON. THIS  
SCENARIO IS UNLIKELY AND BETTER CHANCES REMAIN WELL TO THE EAST  
ACROSS NORTHWEST ARIZONA. SCT-BKN MID/HIGH CLOUDS WILL MOVE IN BY  
12Z AND CONTINUE FOR MUCH OF THE DAY AT HEIGHTS OF 15K FEET OR  
ABOVE.  
 
FOR THE REST OF SOUTHERN NEVADA, NORTHWEST ARIZONA AND SOUTHEAST  
CALIFORNIA...AFTERNOON WIND SPEEDS SHOULD REMAIN AROUND 10 KNOTS  
WITH A FEW GUSTS OF 15-20 KNOTS POSSIBLE. BEST CHANCES TO SEE A  
SHOWER OR STORM WILL REMAIN OVER THE SIERRA (NEAR KBIH) AND MOHAVE  
COUNTY THIS AFTERNOON (BUT EAST OF KIFP/KEED). A STRAY SHOWER OVER  
THE HIGHER ELEVATIONS OF CLARK COUNTY AND THE REMAINDER OF INYO  
COUNTY CAN'T BE RULED OUT THOUGH. GUSTY, ERRATIC WINDS WILL BE THE  
MAIN THREAT WITH ANY ACTIVITY THAT DEVELOPS TODAY, IF ANY. MID/HIGH  
CLOUDS STREAM IN FROM THE SOUTH THIS MORNING WITH SCT-BKN CLOUD  
DECKS AT OR ABOVE 12K FEET.  
 

 
   
CLIMATE
 
 
DAILY RECORD HIGH MAXIMUM TEMPERATURES  
 
FRI 8/14 SAT 8/15 SUN 8/16 MON 8/17  
LAS VEGAS, NV 111 (2016) 111 (2002)* 113 (1939)* 111 (1939)*  
BISHOP, CA 106 (2002) 105 (2002)* 106 (1994)* 106 (2015)  
BARSTOW, CA 112 (2002) 112 (2002)* 114 (1994)* 111 (2015)*  
NEEDLES, CA 117 (2012)* 118 (2019)* 118 (2015)* 117 (1892)*  
KINGMAN, AZ 109 (1933) 106 (1933)* 110 (1933)* 106 (2001)*  
DEATH VALLEY 124 (2002) 124 (2002)* 125 (1994)* 124 (2001)*  
 
DAILY RECORD HIGH MINIMUM TEMPERATURES  
 
FRI 8/14 SAT 8/15 SUN 8/16 MON 8/17  
LAS VEGAS, NV 86 (2007)* 86 (2016)* 88 (2008)* 89 (2015)*  
BISHOP, CA 67 (2015) 65 (1958) 67 (1992) 65 (1992)*  
BARSTOW, CA 81 (1983)* 83 (1996)* 81 (1994)* 82 (2012)*  
NEEDLES, CA 93 (1996)* 92 (1962)* 93 (1892)* 94 (1903)  
KINGMAN, AZ 79 (1996) 78 (1972)* 77 (1917)* 81 (1903)*  
DEATH VALLEY 100 (1924) 97 (2008)* 98 (2008)* 99 (2013)*  
 
*-CURRENT FORECAST MAY BE CLOSE TO CURRENT RECORD VALUES.  
 

 
   
SPOTTER INFORMATION STATEMENT
 
SPOTTERS ARE ENCOURAGED TO REPORT  
ANY SIGNIFICANT WEATHER OR IMPACTS ACCORDING TO STANDARD OPERATING  
PROCEDURES.  

 
 

 
 
UPDATE...VARIAN  
SHORT TERM...ADAIR  
LONG TERM...PIERCE  
AVIATION/CLIMATE...GUILLET/TB3  
 
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:  
HTTPS://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab NV Page
The Nexlab AZ Page
The Nexlab CA Page Main Text Page