Monsoon Watch

azsnowman · #21 Postby **azsnowman** » Sun Jul 04, 2004 7:36 am

I'm not holding my breath just yet but this sounds a *little* more promising...this is this mornings NAFD from NWSFLAG

BY THE WEEKEND...SIGNIFICANT PATTERN SHIFT BEGINS TO TAKE PLACE WITH
HIGH PRESSURE SHIFTING NORTHWARD OUT OF THE GULF OF MEXICO AND OVER
THE CONTINENT. THIS WILL ALLOW THE RIDGE AXIS TO SHIFT NORTHWARD AS
WELL SO THAT AZ WILL SWITCH FROM A SOUTHWESTERLY FLOW TO A MORE
SOUTHERLY FLOW. HAVE INCLUDED LOW POPS FOR FRIDAY INTO THE WEEKEND
FOR WHAT NOW APPEARS TO BE THE APPEARANCE OF THE MONSOON FLOW
PATTERN OVER ARIZONA. DB
&&

.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.

SEAZSky · #22 Postby **SEAZSky** » Sun Jul 04, 2004 1:58 pm

Take Your Pick - When Will "It" Start This Year ? - - -

http://www.wrh.noaa.gov/tucson/monsoon/ ... stats.html

I would say - sometime in the week of July 11-17,
but what do I know..............

Stan - looking south-southeast for the gang to arrive...

#23 Postby **Aslkahuna** » Sun Jul 04, 2004 2:55 pm

The period of 11-17 is also when the GFS is hinting at the start, my revised outlook is 15-20 and my son expects that it will start in force by the 16th when he does his data analysis and briefing stint for NAME.

Steve
8-)

azsnowman · #24 Postby **azsnowman** » Mon Jul 05, 2004 7:27 am

Flip a coin....

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
315 AM MST MON JUL 05 2004

.SYNOPSIS...A WEAK DISTURBANCE WILL BRING SOME CLOUDS AND A FEW
SHOWERS TO THE FOUR CORNERS REGION OF ARIZONA TODAY. OTHERWISE...
HIGH PRESSURE OVER THE REGION WILL RESULT IN SEASONABLE DAYTIME
TEMPERATURES...COOL OVERNIGHT TEMPERATURES...AND MOSTLY CLEAR SKIES
THROUGH MIDWEEK. ON THURSDAY...TROPICAL MOISTURE WILL MOVE NORTHWARD
BRINGING INCREASING CLOUDS AND A SLIGHT CHANCE OF SHOWERS TO MUCH OF
ARIZONA. FOR FRIDAY AND THE WEEKEND...EXPECT PARTLY CLOUDY SKIES AND
A CHANCE OF SHOWERS OVER THE HIGHER TERRAIN.
&&

.DISCUSSION...A WEAK S/W TROUGH WAS MOVING ACROSS THE SRN GREAT
BASIN THIS MORNING BRINGING AN INCREASE IN CLOUDS AND SOME LIGHT
SHOWERS TO THE UT/AZ BORDER REGION. EXPECT THIS FEATURE TO MOVE
QUICKLY TO THE EAST DURING THE DAY TODAY WITH A SCHC OF SHOWERS IN
THE FOUR CORNERS REGION DURING THE DAY. ELSEWHERE...IT WILL BE
MOSTLY SUNNY WITH SEASONABLE HIGH TEMPS. VERY DRY AIRMASS REMAINS IN
PLACE OVER MUCH OF THE STATE AND OVERNIGHT LOW TEMPS CONTINUE TO RUN
WELL BELOW CLIMO WITH A FEW RECORD LOWS STILL BEING SET EACH
MORNING. WILL CONTINUE TO UNDERCUT MOS GUIDANCE FOR THE NEXT FEW
DAYS UNTIL LOW LEVEL MOISTURE BEGINS TO INCREASE MODERATING
OVERNIGHT MIN TEMPS.

.EXTENDED...MODELS CONTINUE TO SUGGEST THAT TROPICAL MOISTURE WILL
MOVE NORTHWARD AROUND THE SUBTROPICAL RIDGE AND ACROSS AZ ON
THURSDAY. BELIEVE THAT GFS SOLUTION IS MUCH TOO AGGRESSIVE WITH
DEVELOPING PCPN. NONETHELESS...WILL INTRODUCE SOME VERY LOW POPS FOR
MUCH OF NRN AZ. WARM TROPICAL LAPSE RATES WILL RESULT IN A FAIRLY
STABLE ENVIRONMENT AND IT APPEARS MORE LIKELY THAT MID LEVEL
MOISTURE WILL RESULT IN MOSTLY CLOUDY SKIES BUT LITTLE PCPN.

PAST FEW MODEL RUNS HAVE ALL SUGGESTED A PATTERN TRANSITION BY THIS
WEEKEND ALLOWING THE SUBTROPICAL RIDGE TO SHIFT NORTHWARD AND
OPENING THE DOOR TO TROPICAL MOISTURE MOVING ACROSS AZ. NEWEST GFS
MODEL IS VERY DIFFERENT AND MAINTAINS A TROUGH AND WESTERLY FLOW
OVER THE SOUTHWEST WELL INTO NEXT WEEK AND BEYOND WITH LITTLE/NO
PCPN. WITH THE SUDDEN FLIP-FLOP OF MODEL SOLUTIONS...HAVE LITTLE
CONFIDENCE IN THE EXTENDED FCST ATTM. DB

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.

SEAZSky · #25 Postby **SEAZSky** » Mon Jul 05, 2004 12:52 pm

Why not "play" with your own desktop thunderstorm:

http://www.wcmsolutions.com/products/th ... storm.html

(cut/paste - if you have to)

The link takes a little time to load all the images and
sounds........Turn up your speakers.....and enjoy.....

Stan

#26 Postby **Aslkahuna** » Mon Jul 05, 2004 7:03 pm

For the first timee this Summer, Today we saw the big CB to our south in Mexico. This usually means that the onset is about 7-10 days away.

Steve
8-)

#27 Postby **Aslkahuna** » Tue Jul 06, 2004 6:48 pm

Standby-something is going to happen this weekend into early next week but whether it's a false start or the real one remains to be seen.

Steve
8-)

weatherlover427 · #28 Postby **weatherlover427** » Wed Jul 07, 2004 8:09 pm

The following excerpt from this afternoon's NWS TUS AFD looks promising (they even introduced small POPs as soon as tomorrow afternoon

):

DURING THE PAST COUPLE OF DAYS VARIOUS NWP PROGS HAVE UNDERDONE THE AMOUNT OF MOISTURE FROM SRN AZ SWD THOUGH RECENT FORECAST CYCLES HAVE ADJUSTED SOMEWHAT TO THIS MOISTURE INCREASE. THUS CONFIDENCE QUITE LOW IN NWP SOLUTIONS REGARDING PRECIP DETAIL THIS FORECAST PACKAGE AND MANUAL ADJUSTMENTS MADE. PER COORD WITH WFO/S PSR/FGZ HAVE OPTED TO ADJUST PRECIP CHANCES FURTHER W THURSDAY INCLUDING 10 PERCENT CHANCE TUCSON VICINITY BUT BELIEVE BEST CHANCE WILL OCCUR MAINLY NEAR ERN MOUNTAINS. PRECIP CHANCES TO INCREASE FRI ESPECIALLY CENTRAL/ERN SECTIONS. HOWEVER STILL BELIEVE SAT AFTERNOON/ EVENING TO BE BEST CHANCE MEASURABLE PRECIP ACROSS FORECAST AREA AS FLOW BECOMES INCREASINGLY SLY/SELY INCREASING AVAILABLE MOISTURE. SOME DRYING MAY OCCUR ACROSS WRN SECTIONS SUN AS WLY FLOW TRIES TO ENCROACH UPON THE AERA BUT STILL BELIEVE MOISTURE WILL REMAIN SUFFICIENT FOR ISOLATED AFTERNOON/EVENING SHOWERS/ THUNDERSTORMS FROM TUCSON VICINITY EWD. MORNING COLLABORATION CALL WITH HPC/CPC AND EXTENDED GFS SOLUTION SUGGESTS AN INCREASE IN POPS WARRANTED MON-WED AS UPPER HIGH TRANSITIONS NWD AND INVERTED TROUGH APPROACHES AREA FROM THE EAST.

#29 Postby **Aslkahuna** » Wed Jul 07, 2004 11:30 pm

Yes, but Pytlak-who's the Lead Forecaster from NWS on NAME is not going for the 'soon this weekend. This will be a precursor event and not the main show as the Upper High is not expected to get into the 4 Corners until 14-16 July.

Steve
8-)

weatherlover427 · #30 Postby **weatherlover427** » Wed Jul 07, 2004 11:48 pm

Which would be a week from today; and the last line or so of the above says

AND EXTENDED GFS SOLUTION SUGGESTS AN INCREASE IN POPS WARRANTED MON-WED AS UPPER HIGH TRANSITIONS NWD AND INVERTED TROUGH APPROACHES AREA FROM THE EAST.

#31 Postby **Aslkahuna** » Thu Jul 08, 2004 2:55 pm

I saw that as well and comment on it in my forecast and monsoon watch on my homepage but the best thing to do with the extended GFS-particularly with regard to the monsoon, is to believe it when you see it. Over the years, I have found that it's best to be conservative in your forecasting and not go off the deep end until it's time to do so.

Steve

#32 Postby **Aslkahuna** » Thu Jul 08, 2004 11:43 pm

We had a classic type of monsoon day today with afternoon thunderstorms building along the mountains and moving NW followed by the outflow boundary from a Sonoran MCS generating evening activity and dumping on us. If this pattern persists into the weekend, then July 8th will be the monsoon start for Cochise County-if not, then we have a classic false start-Time will tell. Big problem is that FHU doesn't put its sounding out on line so we don't know what the true state of affairs in upstairs over us. TUS may only be 50 airmiles away, but there's a major terrain feature within those 50 miles and at times TUS and Sierra Vista could be on different planets weather wise.

Steve
8-)

weatherlover427 · #33 Postby **weatherlover427** » Fri Jul 09, 2004 2:05 am

Looking like some good weather around southeastern AZ at this time, at least on radar. IR satellite shows a nice MCS in northern Mexico moving from the SE to the NW.

Progs here call for a monsoon flow pattern to possibly start setting up by the middle of next week.

azsnowman · #34 Postby **azsnowman** » Fri Jul 09, 2004 6:44 am

MODELS BRING IN SOME DRYING ESPECIALLY IN THE WESTERN PORTION OF THE
FORECAST AREA FOR THE WEEKEND. WILL SHOW A DECREASING TREND WITH
SHOWERS AND THUNDERSTORMS FOR THE WEEKEND...ALTHOUGH NOT AS
SIGNIFICANT AS MODELS INDICATE DUE TO UNCERTAINTY OF RESIDUAL
MOISTURE MOVING INTO THE REGION FROM DAILY CONVECTION TO OUR SOUTH.
BY MONDAY...GFS INDICATES HIGH PRESSURE CENTER TO DEVELOP OVER THE
FOUR CORNERS AREA WITH DEEPER SOUTHEAST FLOW MOVING ACROSS THE
STATE. THIS SHOULD ALLOW FOR A SLOW INCREASE IN PRECIPITATION
CHANCES NEXT WEEK AS THE MONSOON BOUNDARY MOVES WESTWARD AGAIN.

#35 Postby **Aslkahuna** » Fri Jul 09, 2004 3:32 pm

The dewpoints are up again today, the 850mb moisture boundary has surged north of us, the flow at H7 and H5 is SE-SSE at 10-15kt and the temperature break has occurred. The dewpoints have to stay up tomorrow and then we declare the monsoon to have started over Cochise County. TUS may also make the call this weekend for the 8th as well. We shall see.

Steve

azsnowman · #36 Postby **azsnowman** » Fri Jul 09, 2004 7:28 pm

We've had *some sprinkles* today, not even enough to MEASURE though...our dewpoint here at the house actually hit 58° around 1545 MST, let's HOPE like HADES it keeps going up!

Dennis

#37 Postby **Aslkahuna** » Fri Jul 09, 2004 11:19 pm

We've picked up 0.66in of rain the past three days and the dewpoint tonight is in the mid 60's.

Steve

#38 Postby **vbhoutex** » Fri Jul 09, 2004 11:22 pm

Aslkahuna wrote:We've picked up 0.66in of rain the past three days and the dewpoint tonight is in the mid 60's.

Steve

SO is the monsoon declared to be on?

#39 Postby **Aslkahuna** » Sat Jul 10, 2004 10:25 pm

I have to check the dewpoints at FHU, but Tucson may make the call late tonight or tomorrow with the 8th as the start.

Steve
8-)

azsnowman · #40 Postby **azsnowman** » Sat Jul 10, 2004 10:28 pm

vbhoutex wrote:
Aslkahuna wrote:We've picked up 0.66in of rain the past three days and the dewpoint tonight is in the mid 60's.

Steve

SO is the monsoon declared to be on?

YUP....I think so 8-)

We had .23" today with one complex, another .12" with another AND THEN....a WHOPPING .87" with one, I was laying down taking my afternoon nap and BANG, CRASH....a clap of thunder so loud. 8-)

AFDFGZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
900 PM MST SAT JUL 10 2004

.SYNOPSIS...LINGERING LOW LEVEL MOISTURE WILL CONTINUE TO PRODUCE
AFTERNOON AND EVENING THUNDERSTORMS THROUGH THE WEEKEND. STORMS WILL
BE MORE NUMEROUS OVER THE WHITE MOUNTAINS AND AREAS NEAR THE NEW
MEXICO BORDER. A MOIST EASTERLY FLOW WILL DEVELOP EARLY NEXT WEEK AS
A HIGH PRESSURE SYSTEM SETS UP OVER THE FOUR CORNERS REGION. THIS
WILL BRING AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY TO MUCH
OF NORTHERN ARIZONA THROUGH THE UPCOMING WORK WEEK.

&&

.DISCUSSION...A LOWER TO MID LEVEL ANTICYCLONIC CIRCULATION WAS
LOCATED OVER NORTHWEST MEXICO THIS EVENING JUST SOUTH OF THE ARIZONA
BORDER. THIS CIRCULATION WILL CONTINUE TO SLOWLY HEAD NORTHWARD FROM
SUNDAY INTO TUESDAY EVENTUALLY ENDING UP IN THE AREA OF THE FOUR
CORNERS. THE NET RESULT WILL BE A CONTINUED TREND OF INCREASING
MOISTURE OVER ARIZONA. IN ADDITION THE PATTERN WILL BECOME MORE
FAVORABLE TO THE DEVELOPMENT OF THUNDERSTORM COMPLEXES OVER
NORTHWEST MEXICO. STORMS IN MEXICO IN CONJUNCTION WITH A FAVORABLE
SOUTHEASTERLY LARGE SCALE FLOW NORMALLY DELIVERS DEEP MOISTURE TO
ARIZONA. SUNDAY WILL BE A TRANSITION DAY TO A MORE MOIST MONSOON
REGIME. THERE SHOULD BE AN INCREASE IN THUNDERSTORM ACTIVITY ON
SUNDAY...ESPECIALLY EAST OF FLAGSTAFF. BY MONDAY AND TUESDAY DEEP
LAYER MOISTURE WILL COMBINE WITH STRONG DAYTIME HEATING TO PRODUCE
SCATTERED THUNDERSTORMS EACH DAY. CURRENT GRIDS SHOW THIS TREND
INCLUDING LOWER DAYTIME HIGHS AS CONVECTION INCREASES OVER NORTHERN
ARIZONA. JUST A FEW MINOR ADJUSTMENTS TO THE GRIDS/FORECAST.

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