Graphic: |
Run finished at 10 AM.
Heavy Snow forecasted for this morning! The largest snow
and liquid water paths I've seen yet, 400 and 800 g m-2 respectively.
Heaviest snow between 14 and 19 UTC, tapering off by 03 UTC Feb 15.
Lots of cloud water at surface on Mt Werner at -10 C until 21 UTC.
Snow accumulations (rtot) vary between 6-12 cm depending on elevation.
Qv decreasing with time (see graphics file). Note hint of dry layer
around 6 km at 18 UTC (A dry layer between 6-8 km in sounding
was reported by Tian). Another moist layer evident between 2.5
and 4 km after 06 UTC.
Winds decreasing with time and shifting from westerly to a deep
layer of weak northeasterlies after 00 UTC Feb 15.
Would be interesting to see soundings at
23 UTC and 02 UTC to compare with MAPR during this wind shift.
Strong upward vertical velocities modeled above 1.5 km
over NCAR site between 12 and 20 UTC.
133: MM5, Site , Wed 13-Feb-2002 13:34:51 MST, 13 Feb 2002 Run
Run finished at 11 AM.
Next storm to begin influencing Steamboat area around 12 Feb 14
as cloud and snow begin to move in then.
The boundary layer dries out over the next 20 hours. Above 1.5 km
the profile moistens with time beginning around 5 UTC .
Shallow layer of northeasterlies below 500 m shifts to SE after 5 UTC.
Strong upward motion of almost 1 m s-1 associated with moistening
above 1.5 km.
132: MM5, Site , Fri 08-Feb-2002 11:29:11 MST, 08 Feb 2002 Run
Run finished at 11 AM.
Output shows snow showers on and off throughout the 24 hour
period ending 12 UTC on Feb 9. Lots of cloud water around with
the lab being fogged in on and off beginning around 18 UTC
Feb 8. Locally up to 18 cm of snow forecasted (rtot) in the mtns, much
less (2-4 cm) in Steamboat.
Qv again interesting today with moist layer in place between
17 and 23 UTC. I wonder if sonde at 16 Z will be moist or dry.
Would be interesting to compare with another
sounding taken at 18 or 19 UTC.
Strong winds down to the surface. Wind shift takes place around 21 UTC
from southwesterly to northwesterly.
Vertical velocity also interesting with extended period of
upward motion preceeded by two strong updrafts at 18 and
21 UTC.
131: MM5, Site , Thu 07-Feb-2002 16:52:48 MST, 07 Feb 2002 Run
Run completed at 10:30 AM. Once again, no snow is forecast for
24 hour period. Interesting evolving structure in qv might be
worth a sonde launch between now (00 Z) and 06 Z to see if this pans out.
James
130: MM5, Site Boulder, Wed 06-Feb-2002 11:35:57 MST, 06 Feb 2002 (no run)
Due to lack of interesting weather I decided not to run the
model last night as I am trying to catch up on recovering
disk space. Turns out I can only fit output from 3 runs on
a CD.
I saved the input data so we can run at a later time if
needed.
129: MM5, Site Boulder, Wed 06-Feb-2002 11:33:12 MST, 04 Feb 2002 Run
clouds around today and some snow but the model
doesn't allow any to reach the ground at the NCAR site, while
a little does reach the ground up at the lab around 0 Z on the 5th.
looks like a deep front passes through this evening with winds shifting
from westerly to easterly over a deep layer around 04 Z feb 5. Wind
shift is preceeded briefly by a deep layer of upward motion.
128: MM5, Site Boulder, Wed 06-Feb-2002 11:32:08 MST, 03 Feb 2002 Run
No snow or cloud forecasted for the next 24 hours.
Winds shift from NW to SW between 0 and 3 km AGL
around 00 UTC on Feb 4. Easterly winds again show up below
700 m. Overall winds are light.
Vert. vel. are weak also, but an extended period of downward motion
is forecast below 700 m between 18 and 00 UTC.
127: MM5, Site Boulder, Wed 06-Feb-2002 11:29:06 MST, 02 Feb 2002 Run
Hi All, Todays run is on the web. I found a new more reliable source
for input data that is available earlier in the day thanks to help from the
folks from NCEP.
Today's run not too interesting with only some high cirrus passing over head
in the afternoon.
Vertical velocities are mostly downward below 1 km. Winds are rather light
from the east below 700 m and west aloft.
126: MM5, Site Boulder, Fri 01-Feb-2002 11:17:21 MST, no run today
The data files for MM5 run were unavailable last night
and this morning so no runs have been made. Will
try again tonight.
Addendum: The input files were finally obtained this
afternoon and stored in realtime/20020201/eta* so a
run can be made at a later time.
125: MM5, Site Boulder, Thu 31-Jan-2002 12:16:50 MST, 31 Jan 2002 Run
Late run again caused by late availability of model inputs.
Simulation shows a brief period of some light snow possible late this
afternoon (00Z feb 1).
Winds near surface below 300 m are light and variable with
periods when wind shifts from easterly to westerly. Above 1 km
winds shift from NE to WNW and then west by the end of the run.
Note: vectors only indicate wind direction. The variations in
length are meaningless as speed is color coded.
124: MM5, Site Boulder, Wed 30-Jan-2002 16:06:34 MST, 30 Jan 2002 Run
MM5 output now available for today. Late start due to late availability
of the model input data.
Forecasted winds are very interesting today with lots of directional and
speed shear. Vertical velocities are small ( < 20 cm s-1) and mostly
positive until the end of the period when some stronger upward motion is
forecast near the surface.
Clouds to dissipate and snow to end around 22 UTC at NCAR site. Liquid
water around during first 6 hours of the forecast period at the Lab.
123: MM5, Site Boulder, Tue 29-Jan-2002 13:16:01 MST, output note
New time-height plot now generated which plots wind field
with color coded vector arrows.
122: MM5, Site Boulder, Tue 29-Jan-2002 11:10:01 MST, 29 Jan 2002 Run
Model run completed at 11 AM MDT. It shows a good amount of snow
through the 24 hour period ending 12Z on Jan 30, with snow becoming
lighter after 06Z on the 30th. Not alot of cloud water around but
enough that there could be intermittent riming events. I
wonder if they are observing much at the lab.
Winds switch from northeasterly below 500 m AGL to southwesterly above
1 km and are fairly strong aloft. Vertical velocity over NCAR site is
upward at 10-30 cm s-1 through about 03Z, then subsidence begins
to take over.Predicted snowfall at the NCAR site from 00Z Jan 29 to
12 Z Jan 30 is 6 mm liq equiv (RTOT) or about 6-10 cm of snow. Locally
as much as 20 cm of snow are possible in preferred locations.
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