Area forecast discussion 
National Weather Service Tucson Arizona 
900 PM MST Friday may 29 2015 

Synopsis...building high pressure will bring a strong warming trend 
into early next week. High temperatures will exceed 100 degrees this 
weekend for Tucson...Safford and the lower deserts...with middle to 
upper 90s elsewhere. There is a slight chance of afternoon and 
evening showers and thunderstorms east of Tucson through Monday. 
Otherwise...dry conditions will prevail into the upcoming week. 


Discussion...Tucson international fell just short of 100 today but 
will very likely hit it tomorrow. A strong ridge over Arizona will 
bring the heat Saturday and Sunday. 850-700mb thicknesses maximum out on 
Sunday afternoon and support up to a 104 at tia. Current forecast 
trends look good. Please see the previous discussion below for 
additional details. 


Aviation...valid through 31/06z. 
Clearing trend tonight with mostly clear skies late tonight and 
Saturday morning. Ktus vicinity-eastward there will be a few to 
occasionally broken clouds at 8-12k feet above ground level Saturday afternoon. 
There is a slight chance of -tsra/-shra mainly east of a ksad-kfhu 
line Saturday afternoon. Surface wind Saturday afternoon will be 
westerly/northwesterly at 10-15 kts with occasional gusts to around 20 kts. 
Otherwise...surface wind will be less than 10 kts. Aviation 
discussion not updated for taf amendments. 


Fire weather...there is a slight chance of showers and/or 
thunderstorms east of Tucson to the New Mexico border Saturday 
through Monday. The best chance for this activity will be Sunday. 
The coverage of showers and/or thunderstorms Sunday afternoon and 
evening may be as far west as the galiuro/Pinaleno Mountains in 
Graham County...and perhaps as far west as the Dragoon Mountains in 
Cochise County. Most rainfall amounts will be light...with generally 
trace amounts to perhaps one tenth of an inch...although 
locally heavier amounts may occur. The main concern will be the 
potential for brief strong...gusty and erratic winds associated with 
any thunderstorms. 

Otherwise...dry conditions will be the rule through next Friday. 
Daytime minimum relative humidity values will generally be in the 
single digits to middle teens. Expect normal diurnal wind trends 
into early next week...with some gustiness during the afternoon and 
early evening hours due to strong daytime heating. Somewhat stronger 
winds should occur during the latter part of next week as a low 
pressure system deepens west of the area. 


Previous discussion...upper ridge axis adjacent the West Coast this 
afternoon will amplify and move eastward into the southwestern Continental U.S. This 
weekend. Meanwhile...some increase in lower and middle-level moisture 
will occur mainly near the New Mexico border Sat followed by a more 
pronounced moisture increase especially east of Tucson sun. There is 
a slight chance of showers and thunderstorms across the White 
Mountains Sat afternoon/ evening. A few showers/thunderstorms may occur 
further southward adjacent the New Mexico border Sat afternoon/evening. 
The coverage of showers/thunderstorms should extend further westward Sun 
afternoon/evening...perhaps as far west as the galiuro/Pinaleno 
Mountains in Graham County...and perhaps near the Dragoon Mountains 
in Cochise County. 

Most rainfall will be quite light...with amounts ranging from a 
trace to a few hundredths of an inch or so. The main concern will be 
from brief strong and gusty winds associated with any thunderstorms. 
The upper ridge axis will move east of the area Monday allowing for 
some increase in westerly flow aloft. There will still be enough moisture 
to maintain a slight chance of showers/thunderstorms across the White 
Mountains Monday afternoon/evening. 

The flow aloft will become increasingly westerly/southwesterly Tuesday-Thursday in 
response to a deepening upper trough over the western Continental U.S.. there 
continued to be fairly substantial differences between the 
European model (ecmwf)/GFS/CMC regarding the amplification of this upper trough 
during the latter part of next week. In essence...the European model (ecmwf) depicted 
a considerably deeper trough versus the GFS/CMC...and the GFS 
depicted the least amplified solution. Curious to note that the GFS 
produced light rainfall amounts near the international border Thursday 
and Thursday night. However...the European model (ecmwf) held light rainfall amounts 
until Friday. For this forecast issuance...have maintained precipitation-free 
conditions during the latter part of next week. 

A warming trend will occur this weekend...with high temperatures sun and 
Monday to average about 3-7 degrees above normal. A very gradual decrease 
in daytime is expected to occur by the middle of next week. 


Twc watches/warnings/advisories...none. 



Visit US on at weather.Gov/Tucson 


National Weather Service Glossary of Abbreviations
Back to forecast page
Non-Expanded Version (with abbreviations)

Units: English | Metric

Find the Weather for any City, State or Zipcode, or Country:

U.S. State List | Severe Weather | Tropical Storms | Ski Conditions
United States | Canada | Central America | South America | Asia | Europe | Australia | Africa | Islands

Weather Underground Copyright© 2015
Weather Underground, Inc.

Questions or Comments? Contact Us