Sunday, April22, 2018 L-36.com


Marine Weather and Tides
South Lake Tahoe, CA

Version 3.4
What's New / NOTES
3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.

Sunrise 6:10AMSunset 7:45PM Sunday April 22, 2018 11:00 AM PDT (18:00 UTC) Moonrise 11:06AMMoonset 12:52AM Illumination 49% Phase: First Quarter Moon; Moon at 7 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
    EDIT      (on/off)   Help
7 Day Forecast for Marine Location Near South Lake Tahoe, CA
   Hourly   EDIT   Help
location: 38.91, -120.01     debug


Area Discussion for - Reno, NV
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus65 krev 220826
afdrev
area forecast discussion
national weather service reno nv
126 am pdt Sun apr 22 2018

Synopsis
Much warmer temperatures are expected through next week with mainly
dry conditions. A wave passing to the north today will bring
increased afternoon and evening winds. Low pressure developing off
the california coast will bring increasing chances for showers
and a few thunderstorms from mid week into the weekend.

Short term
The main change for this cycle was to re-introduce thunderstorm
chances for Tuesday afternoon. Otherwise, the forecast largely
remains unchanged with warm temperatures and dry conditions
continuing. Synoptic weather features include a weak passing wave
this afternoon that will shift regional winds, then building high
pressure over the western united states Monday and Tuesday.

Isolated thunderstorms will be possible this afternoon for extreme
northern washoe county as a passing wave destabilizes the
atmosphere near the oregon border. With prevailing flow out of the
west weakening convergence along the eastern sierra,
thunderstorms are less likely for the sierra crest this afternoon.

Still, we could get a very isolated build-up over the higher
terrain, but generally less than a 10% chance.

Flow turns more northerly for Monday with a slight "cool-down"
from the upper 70s for western nevada and around 70 for sierra
valleys to the mid 70s and upper 60s respectively. While high
pressure starts building over the region, this flow regime will
keep surface convergence at a minimum resulting in no appreciable
chances of afternoon thunderstorms.

Convergence Saturday afternoon was sufficient to kick off a
couple of cells over the sierra south of lake tahoe with a
slightly eastward position of the ridge axis in central nevada.

Similarly, the ridge axis is anticipated to shift eastward and
amplify Tuesday afternoon. With easterly flow weakening as the
pressure gradient weakens and afternoon temperatures heading back
into the upper 70s to around 80 for central nevada, convergence
will increase in the eastern sierra. While gfs's convective scheme
continues to be an outlier with widespread coverage of showers
and thunderstorms over sierra locations, other models also favor
at least a slight chance of convection. Since several model suites
match the conceptual model for thermally-induced-convergence-
based-convection, slight chances for thunderstorms were re-
introduced for Tuesday afternoon. Current forecast chances for
thunderstorms along the sierra crest from just west of lake tahoe
through mono county are around 20%. If you have plans outdoors
Tuesday afternoon, you may want to check the forecast over the
next couple of days. Boyd

Long term Wednesday onward...

the main focus for the long term continues to be the problematic
closed off low in the eastern pacific and how it progresses inland.

These types of lows are notoriously tricky to forecast and
forecaster confidence Friday onward is very low.

For Wednesday and Thursday, there is decent confidence in the low
remaining offshore. Increasing moisture and instability in southerly
flow ahead of the low will bring chances for showers and
thunderstorms each afternoon and evening. This will be especially
true for the sierra and adjacent lower valleys of western nevada,
as well as the sweetwater and pine nut mountains.

The operational GFS has continued the trend of bringing the low
directly over california and nevada for the weekend while the ec
continues its trend of bringing the low inland farther north into
oregon. Ensembles for both models are highly dispersive with no real
solid solutions able to be gained from the data. For now, will
maintain the general idea in the forecast, keeping chances for
showers and thunderstorms and a slight cool down for the weekend,
but this is really a middle ground. Keep in mind, if the low tracks
north, temperatures may be mild with drier conditions, while if it
takes a direct track over the region the weekend could be much
colder and wetter. -dawn

Aviation
Vfr conditions to continue today with some cumulus development
possible over the sierra in the afternoon and a stray shower or
thunderstorm possible near the oregon idaho border. Fog did not
form at ktrk the past couple of nights, so thinking the odds are
low for fog formation. A weak wave passing north of the region and
warm afternoon temperatures will contribute to increasing
westerly breezes this afternoon with peak gusts of 20-25 kts.

Afternoon showers and thunderstorms are possible Tuesday through
Friday which could bring lowered CIGS vis, mountain obscuration,
turbulence, and erratic winds. It's too early to tell if a storm
will directly impact a terminal at this time. -dawn

Rev watches warnings advisories
Nv... None.

Ca... None.

For more information from the national weather service visit...

http: weather.Gov reno


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
South Lake Tahoe, Lake Tahoe Airport, CA1 mi68 minN 010.00 miFair56°F35°F46%1017.6 hPa
Carson City Airport, NV24 mi66 minWSW 310.00 miFair61°F35°F39%1019.6 hPa

Wind History from TVL (wind in knots)
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
Last 24hr5N8N84NE6CalmCalmCalmCalmCalmCalmSW3S6CalmS4CalmS3CalmCalmCalmCalmCalmCalmS10
G18
1 day agoN8NE8NE103NE9NE7N5CalmCalmCalmCalmCalmS5CalmCalmCalmCalmSW33CalmS3SE4NE6--
2 days agoNE9NE6NE10
G16
NE9NE10
G16
N6NE10N5N3CalmCalmCalmCalmS4CalmS4S4S5S3S4SE4E3Calm5

Tide / Current Tables for Sacramento, Sacramento River, California
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Sacramento
Click for MapNote: These data apply only during low river stages.

Sun -- 01:54 AM PDT     2.25 feet High Tide
Sun -- 01:57 AM PDT     Moonset
Sun -- 06:20 AM PDT     Sunrise
Sun -- 08:14 AM PDT     0.76 feet Low Tide
Sun -- 12:10 PM PDT     2.72 feet High Tide
Sun -- 12:12 PM PDT     Moonrise
Sun -- 02:46 PM PDT     First Quarter
Sun -- 07:49 PM PDT     Sunset
Sun -- 09:45 PM PDT     -0.08 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.62.12.32.11.81.51.10.90.80.91.52.32.72.72.52.11.71.20.80.40.1-0-0.10.3

Tide / Current Tables for Sacramento #4, Sacramento River, California
   EDIT      (on/off)   Help   One Week of Data
Sacramento #4
Click for Map
Sun -- 01:54 AM PDT     2.24 feet High Tide
Sun -- 01:57 AM PDT     Moonset
Sun -- 06:20 AM PDT     Sunrise
Sun -- 08:14 AM PDT     0.75 feet Low Tide
Sun -- 12:11 PM PDT     2.71 feet High Tide
Sun -- 12:12 PM PDT     Moonrise
Sun -- 02:46 PM PDT     First Quarter
Sun -- 07:49 PM PDT     Sunset
Sun -- 09:44 PM PDT     -0.08 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.62.12.22.11.81.51.10.90.80.91.52.32.72.72.52.11.71.20.80.40.1-0-0.10.3

Weather Map and Satellite Images
       (on/off)   HelpWeather Map
wmap_P
GOES Local Image of CentralWestCoast    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Reno, NV (14,3,4,5)
      (on/off)   Help

Ground Weather Radar Station Reno, NV
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.