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Area Forecast Discussion (AFD)

Issued by Denver/Boulder, CO (BOU)

                            
000
FXUS65 KBOU 182112
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
312 PM MDT Tue Jun 18 2019

.SHORT TERM...(This evening through Wednesday)
Issued at 310 PM MDT Tue Jun 18 2019

Generally weak to moderate convection has developed 
over the mountains and plains so far this afternoon. Since there was 
very little sunshine this morning and no low level inversion, weak 
showers and storms have developed very quickly in most locales. So 
far rainfall amounts have generally been less than a quarter of an 
inch per hour. Instability a bit better over the plains with better 
rainfall rates expected.  Expect showers and thunderstorms to 
continue at least through this evening as we are under weak ascent 
from upper wave over Western Wyoming. Wave will move across Colorado 
later tonight with a gradual trend from west to east. 

For Wednesday, we will transition to a drier and stronger northwest 
flow pattern across Northern Colorado. Precipitable water values 
will drop to around a half of an inch over the Front Range to 
around 3/4 of an inch over the plains. Could still be a few 
thunderstorms, mainly over the far northeast plains of Colorado. 
Temperatures will be warmer as well with more sunshine expected. 

.LONG TERM...(Wednesday night through Tuesday)
Issued at 310 PM MDT Tue Jun 18 2019

A few thunderstorms may be ongoing over the far northeastern
plains Wednesday evening, otherwise skies should be clearing with
near to warmer than average overnight lows. 

The upper low will dig deeper into the Great Basin Thursday to
turn flow aloft from west to southwest to bring the warmest,
though near average, day of the week to the area. The jet will 
sink further south to increase shear. This along with increasing 
moisture into the plains will bring a chance of severe 
thunderstorms across the northern and northeastern plains 
Thursday. With the jet nearby, a chance of showers and storms will
likely last through the night. The upper low will dig further 
south into NV and UT Friday to sink the jet further, allowing for 
a cold front to push into the area. Currently the NAM and ECMWF 
are quicker than the GFS, having it into the area before noon, 
compared to later in the afternoon per the GFS. Either way, will 
have cooler max temperatures Friday, along with scattered to 
numerous showers and thunderstorms, with a chance of stronger 
storms further south toward the Palmer Divide.

Saturday will be cool and showery as the upper trough passes
overhead, with Sunday clearing out as the subsidence on the
backside moves in from the west. Monday and Tuesday will be warm
and dry as an upper ridge begins to build up from Mexico. 


&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 310 PM MDT Tue Jun 18 2019

Scattered showers and a few thunderstorms will continue to move
across the terminals through this evening but overall convection
has been on the weaker side. Stronger storms will likely remain
east of the local terminals. Expect drainage winds later tonight
and so any stratus will remain east of the terminals. Expect a
mainly dry day on Wednesday with VFR conditions. 

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...Entrekin
LONG TERM...Kriederman
AVIATION...Entrekin