Click Here to Visit World Wave Expeditions.com!
See Video Forecast HERE (12/9)
Buoys | Buoy Forecast | Models: Wave - Weather - Surf - Altimetry - Snow | Pacific Forecast | QuikCAST | El Nino | Tutorials | Great Circles | Video

Google

Stormsurf Mobile App

Create Your Own Surf Forecast
Swell Calculator
Swell Decay Tables
Sea Height Tables
Swell Category Table
Convert from GMT:
 
 to timezone:

---
Pacific Storm and Surf Forecast
Updated: Saturday, December 17, 2016 1:08 PM
Buoys: Northern CA - Southern CA - Hawaii - Gulf of Alaska - Pacific Northwest
Buoy Forecast:
Northern CA - Southern CA - Hawaii - Gulf of Alaska - Pacific Northwest
Pacific Links:  Atmospheric Models - Buoy Data - Current Weather - Wave Models
Forecast Archives: Enter Here
A chronology of recent Mavericks Underground forecasts. Once you enter, just click on the HTML file forecast you want to review (e.g. 073199.html equals July 31, 1999). To view the maps that correspond to that forecast date, select the html file labeled 073199 maps.html
4.0 - California & 3.3 - Hawaii
Using the 'Winter' Scale
(See Swell Category Table link at bottom of page)

Probability for presence of largest swells in near-shore waters of NCal, SCal or Hawaii.    

Issued for Week of Monday 12/19 thru Sun 12/25

Swell Potential Rating Categories
5 = Good probability for 3 or more days of Significant swell
4 = Good probability for 1-2 days of Significant swell
3 = Good probability for 3 or more days of Intermediate/Advanced swell
2 = Good probability for  1-2 days of
Intermediate/Advanced swell
1 = Good probability for 3 or more days of Impulse or Windswell
0 = Low probability for 1-2 days of Impulse or Windswell   

N. Dateline Swell Heading East
Another Forecast Right Behind

BUOY ROUNDUP
On Saturday, December 17, 2016 :

  • Buoy 106 (Waimea): Seas were 11.5 ft @ 13.3 secs with swell 7.7 ft @ 13.0 secs from 333 degrees.
  • Buoy 46025 (Catalina RDG): Seas were 5.7 ft @ 7.1 secs with swell 4.9 ft @ 6.5 secs from 266 degrees. Wind northwest 6-8 kts. Water temperature 59.9 degs. At Ventura swell was 2.5 ft @ 6.4 secs from 274 degrees. At Santa Monica swell was 4.3 ft @ 6.8 secs from 268 degrees. At Camp Pendleton swell was 3.6 ft @ 7.5 secs from 235 degrees. Southward at Pt Loma swell was 5.5 ft @ 8.3 secs from 280 degrees.
  • Buoy 46012 (Half Moon Bay)/029 (Pt Reyes): Seas were 8.7 ft @ 7.7 secs with swell 7.0 ft @ 8.0 secs from 316 degrees. Wind northwest 18-21 kts at the buoy. Water temp 53.4 degs.
    Notes

    46006, 46059, New! Hi-Res Buoy Dashboards (at the bottom of the page)

Swell Classification Guidelines

Significant: Winter - Swell 8 ft @ 14 secs or greater (11+ ft faces) for 8+ hours (greater than double overhead).
Summer
- Head high or better.
Advanced: Winter - Swell and period combination capable of generating faces 1.5 times overhead to double overhead (7-10 ft)
Summer - Chest to head high.
Intermediate/Utility Class: Winter - Swell and period combination generating faces at head high to 1.5 times overhead (4-7 ft).
Summer
- Waist to chest high.
Impulse/Windswell: Winter - Swell and period combination generating faces up to head high (1-4 ft) or anything with a period less than 11 secs.
Summer
- up to waist high swell. Also called 'Background' swell.

Surf Heights for Hawaii should be consider 'Hawaiian Scale' if period exceeds 14 secs.

PACIFIC OVERVIEW
Current Conditions
On Saturday (12/17) in North and Central CA locally generated northwest windswell was producing waves in the chest high range on the sets at exposed breaks and clean but lumpy early. Protected breaks were waist to chest high. At Santa Cruz surf was flat and clean. In Southern California up north surf was thigh high and clean at top breaks. Down in North Orange Co surf northwest windswell was producing waves at waist high or so and lumpy but clean. In San Diego northwest windswell was chest high and clean early. Hawaii's North Shore was getting north local windswell at 8 ft and raw and lumpy with Kona winds in control. The South Shore was flat and clean. The East Shore was getting north windswell with waves 2-3 ft overhead and clean with moderate southwest winds.

See QuikCASTs for the 5 day surf overview or read below for the detailed view.

Meteorological Overview
Hawaii was getting larger raw local north windswell from a cutoff low that produced 25 ft seas just 350 nmiles north of the Islands on Fri (12/16). But it is fading. A storm developed Wed-Thurs (12/15) with up to 47 ft seas on the Northern Dateline region aimed east. Small swell is possible for Hawaii and the US West Coast. Another gale is to develop in the extreme Northwest Gulf of Alaska Sat-Mon (12/19) producing up to 43 ft seas aimed east then fading some but tracking slowly east through the Northern Gulf Tues-Thurs (12/22) producing more 30-33 ft seas aimed east. Perhaps a small storm is to develop off Japan Fri-Sat (12/24) with up to 42 ft seas aimed east. The jetstream is looking good and forecast to hold decently as the Active Phase of the MJO tries to get footing in the West Pacific.

SHORT- TERM FORECAST
Current marine weather and wave analysis.cgius forecast conditions for the next 72 hours

North Pacific

Overview
Jetstream
On Saturday AM (12/17) the jetstream was consolidated pushing east-northeast off Japan with winds to 200 kts reaching into the Northwestern Gulf of Alaska forming a broad trough off Kamchatka reaching almost to the north dateline region providing support for gale development. The jet .cgiit over the Gulf of Alaska some then consolidated over San Francisco pushing inland from there. Over the next 72 hours the jet is to continue holding consolidated and pushing east reaching the coast of Washington on Mon AM (12/19) with winds 140-150 kts from just west of the dateline into the US West Coast and a broad but gentle trough over the North Dateline region moving to the Northwestern Gulf on Tues (12/20) and fading. Beyond 72 hours winds in the jet are to weaken briefly then start rebuilding on Fri (12/23) to 180 kts mainly over the dateline while falling south digging out a trough and pushing east into the Northern Gulf on Sat (12/24) offering good support for gale development. And another trough is to start forming over the Southern Kuril Islands being fed by a pocket of 150 kt winds there again offering support for gale development. An improving jetstream pattern seems possible.

Surface Analysis
On Saturday (12/17) swell from a cutoff low previously north of Hawaii was fading in Hawaii (see Hawaiian cutoff low below). Also a solid storm developed off the Kurils Wed-Fri (12/160 producing sideband swell tracking towards Hawaii and the US West Coast (See Solid Kuril Storm below)

Over the next 72 hours another gale is forecast developing starting Sat AM (12/17) on the dateline just south of the Aleutians with 45 kt northwest winds and seas on the increase. In the evening winds are to be building to 55-60 kts from the west just south of the Central Aleutians with 40 ft seas at 51N 179W over a modest sized area. On Sun AM (12/18) fetch is to stall with 50 kt west winds just south of the Aleutians with seas building to 43 ft at 51N 174W (308 degs NCal) aimed east targeting north CA and the Pacific Northwest. In the evening fetch is to fade from 45 kts from the west in the same location with seas fading from 39 ft over a solid area at 52N 171W (308 degs NCal). On Mon AM (12/19) fetch is to fade from 40 kts from the west with seas fading from 35 ft at 51N 166W with secondary fetch moving in from the west. Solid swell is possible for exposed breaks from Central CA northward ad limited sideband swell for Hawaii.

Secondary fetch is to be racing off north Japan towards the dateline Sun (12/19) reaching the dateline Monday and tracking into the Western Gulf in the evening with winds building to 45 kts and seas 32 ft at 46N 166W aimed east (297 degs NCal). On Tues AM (12/20) 40-45 kt west winds to continue east generating a broad area of 30-32 ft seas up at 50N 154W (308 degs NCal). Fetch is to be fading in the evening from 35 kts from the west winds seas fading from 32 ft at 52N 150W (311 degs NCal). This system is to dissipate thereafter. More reinforcing swell is possible for the US West Coast.

 

Hawaiian Cutoff Low
A cutoff low started to form 400 nmiles north of Hawaii on Thurs AM (12/15) producing 30-35 kt north winds with seas building. In the evening fetch built to 45 kts over a tiny area still 40 nmiles north of the Islands aimed directly at them with seas building from 24 ft at 29N 162W (350 nmiles NNW of Kauai). Fetch faded from 40 kts Fri AM (12/16) with seas 26 ft at 28N 161W. This system remained stationary fading slowly Fri PM with winds dropping from 30 kts and seas slowly fading from 22 ft at 26N 161W then gone 12 hours later. Large raw local north windswell possible for Maui and the Islands west of there.

Oahu: Expect windswell arrival on Fri afternoon (12/16) building to 10 ft @ 13-14 secs late (13 ft). Swell fading Sat (12/17) from 8.6 ft @ 12 secs (10 ft). Swell dissipating over night. Swell Direction: 345+ degrees

 

Solid Kuril Storm
A small storm developed well off the Kurils on Wed PM (12/14) tracking northeast with winds 45 kt from the west and seas building to 27 ft at 42N 161E. On Thurs AM (12/15) winds built to 55-60 kt from the west but positioned just south of the Central Aleutians on the Dateline with 42 ft seas at 49N 170E targeting mainly the Pacific Northwest and the Central Aleutians. In the evening fetch was fading from 50-55 kts over a solid area south of the Aleutians from the west with seas fading from 47 ft at 51N 178E targeting mainly the Pacific Northwest and starting to impact the Central Aleutians directly. This system was fading out on Fri AM (12/16) with winds dropping from 40 kts just south of the Aleutians and seas fading from 37 ft at 51N 178W. Limited sideband swell is possible for Hawaii with better energy tracking towards the Pacific Northwest.

Hawaii: Expect swell arrival on Sun (12/18) slowly building to 4.2 ft @ 17 secs (7 ft) just before sunset. Swell fading Mon AM (12/19) from 3.6 ft @ 13-14 secs (4.5-5.0 ft). Residuals fading Tues AM (12/20) from 3 ft @ 12-13 secs (3.5-4.0 ft). Swell Direction: 320 degrees

North CA: Expect swell arrival on Mon AM (12/19) slowly building to 3.8 ft @ 18 secs (6.5-7.0 ft) late and inconsistent. Swell peaking Tues AM (12/20) at 5.6 ft @ 16 secs 9.0 ft) and slightly more consistent. Swell fading on Wed AM (12/21) and possibly being overtaken by new stronger swell. Swell Direction: 308 degs (shadowed in the SF Bay Area).

 

  North Pacific Animations: Jetstream - Surface Pressure/Wind - Sea Height - Surf Height

 

Tropical Update
No tropical systems of interest are being monitored.

California Nearshore Forecast
On Saturday AM (12/17) high pressure at 1034 mbs was building 600 nmiles off the Oregon-CA boarder generating north winds at 15-20 kts along the North and Central CA coast a bit off the shore but Southern CA was protected. High pressure is to hold on Sunday but start ridging into Oregon with winds turning northeast at 10-15 kts over North and Central CA fading to 10 kts on Monday then 10-15 kts Tuesday still from the north-northeast early. A front is to push down the North Coast later Tues but fading over Pt Arena with rain only making it south to there. Wed AM northeast winds to continue at 15 kts. Winds light early Thurs (12/22) as another front queues up with light rain down to Bodega Bay late afternoon. High pressure behind turning winds to the north for all of North and Central CA late afternoon building to 20 kts late. A dusting of snow for Tahoe. North winds in control of North and Central CA at 20 kts on Fri and Sat (12/24) but maybe turning northeast nearshore later Saturday.

 

South Pacific

Overview
Surface Analysis  
No swell of interest was in the water and no swell producing fetch of interest was occurring.

Over the next 72 hours no swell producing fetch of interest is forecast.

 

South Pacific Animations: Jetstream - Surface Pressure/Wind - Sea Height - Surf Height

 

QuikCAST's

 

LONG-TERM FORECAST
Marine weather and forecast conditions 3-10 days into the future

North Pacific

A tiny gale is to develop on the dateline Thurs (12/22) with 45 kt northwest winds and seas to 26 ft in the evening at 46N 172W aimed somewhat at Hawaii but swinging to the east. fetch is to fade from 35 kt Fri AM (12/23) with seas fading from 26 ft at 48N 163W targeting the US West Coast, then dissipating. Something to monitor.

A far broader gale is to develop Fri PM (12/23) just off North Japan with winds 45 kt from the west and seas building from 30 ft at 37N 151E targeting Hawaii. Fetch is to build Sat AM (12/24) to 50 kts from the northwest with seas building to 41 ft at 42N 159E again targeting Hawaii well. The gale is to be lifting northeast in the evening with winds fading from 40 kts and seas fading from 41 ft at 44N 166E.

 
South Pacific

Beyond 72 hours no swell producing fetch of interest is forecast.

More details to follow...

SST Forecast Suggests La Nina to Dissipate in Next 3 Months

The Madden Julian Oscillation is a periodic weather cycle that tracks east along the equator circumnavigating the globe. It is characterized in it's Inactive Phase by enhanced trade winds and dry weather over the part of the equatorial Pacific it is in control of, and in it's Active Phase by slack if not an outright reversal of trade winds and enhanced precipitation. The oscillation occurs in roughly 20-30 day cycles (Inactive for 20-30 days, then Active for 20-30 days) over any single location on the.cgianet, though most noticeable in the Pacific. During the Active Phase in the Pacific the MJO tends to support the formation of stronger and longer lasting gales resulting in enhanced potential for the formation of swell producing storms. Prolonged and consecutive Active MJO Phases help support the formation of El Nino. During the Inactive Phase the jet stream tends to .cgiit resulting in high pressure and less potential for swell producing storm development. The paragraphs below analyze the state of the MJO in the Pacific and provide forecasts for MJO activity (which directly relate to the potential for swell production).

Overview: The 2014-2016 El Nino is gone. La Nina has developing but generally weak.

KWGA/Equatorial Surface Wind Analysis & Short-term Forecast:
Analysis (TAO Buoys): As of Friday (12/16) east winds were over the entire equatorial Pacific but calm to light northwest over the Kelvin Wave Generation Area. The KWGA is on the equator from 135E-170W and 5 degs north and south. Anomalies were weak over the equatorial East Pacific and neutral over the KWGA. This is a good turn of events. Previous east anomalies over the KWGA were attributable to La Nina and are being modulated by the MJO.
1 Week Forecast (GFS Model): Modest east anomalies were modeled over the dateline but weak west anomalies over the western KWGA. The forecast suggests west anomalies are to build at modest strength holding through 12/19. then fading some into 12/24 with weak east anomalies backtracking west from the dateline. The first real easterly wind burst from this La Nina started on 9/23 and continued into 12/13, fading some, but likely to return. Easterly anomalies have been consistent, pulsing stronger at times, then weaker, attributable to La Nina and modulated by the MJO.

Kelvin Wave Generation Area wind monitoring model: West and East

Longer Range MJO/WWB Projections:  
OLR Models: As of 12/16 a weak Active MJO signal was present in the West Equatorial Pacific. The statistic model projects it dissipating 5 days out and a neutral MJO signal remaining through the end of the 15 day run of the model. The dynamic model depicts the Active Phase of the MJO is to build slightly and hold into day 15. This is the preferred outcome.
Phase Diagrams 2 week forecast (ECMF and GEFS): (12/17) The ECMF model indicates the Active Phase of the MJO is weak and barely discernible in the west Pacific and is to hold that way for the next 2 weeks. GEFS model depicts mostly the same thing but with the Active Phase building slightly through the 2 week window.
40 day Upper Level Model: (12/17) This model depicts a modest Active Phase of the MJO moving into the West Pacific and it is to move east into Central America while weakening on 1/11. A modest Inactive Phase is to develop behind that in the West Pacific on 1/6 tracking east to the East Pacific 1/26. This model runs about 2 weeks ahead of what happens at the surface.
CFS Model - 3 month (850 mb wind): (12/17) This model depicts a weak Inactive MJO signal over the dateline with modest east anomalies there too while the Active Phase of the MJO starts building in the far West KWGA and weak west anomalies there also. The Inactive Phase is to fade on 12/29 with the Active Phase building in the West Pacific moving to the dateline through 1/26 with weak west anomalies in.cgiay. A weak Inactive Phase is to try and follow near 2/2 but fade quickly, with the Active Phase rebuilding on the dateline 2/11-2/27 with solid west anomalies forecast. But overall the MJO signal is projected to be very weak and this pattern is to hold as we move deeper into Winter. We suspect La Nina is having the effect of dampening the MJO, and producing weak east anomalies in the KWGA but not producing an outright bias towards the Inactive Phase of the MJO. Likewise the MJO is serving to dampen the effects of La Nina when in the Active Phase.

CFSv2 3 month forecast for 850 mb winds, MJO, Rossby etc

Subsurface Waters Temps
TAO Array: (12/17) Actual temperatures remain stratified with warm water in the West Pacific at 30+ degs C (reaching east to 165E) and the 28 deg isotherm line reaching to 177W and steep, suggesting a hard break between warm water in the west and cool water in the east at depth. This is expected with La Nina in.cgiay. Anomaly wise, warm anomalies at +1-2 degs rule from the West Pacific to 180W.  Neutral to weak negative anomalies are east of there to Ecuador at no more than -1.0 degs, with warmer anomalies building under it pushing up from 150 meters down and building in coverage daily. The hi-res GODAS animation posted 12/9 depicts this pocket of of cooler water -1-2 degs below normal in the East Pacific and getting weaker. La Nina is in control of the ocean at depth, but not strongly so and weakening and getting shallower.
Sea Level Anomalies: (12/9) Negative anomalies at -5.0 cm with a few small pockets to -10 cm rule the equatorial Pacific from Ecuador to the dateline and 5 degs north and south. This is an upgrade from months past where anomalies were up to -10 cm and suggest La Nina is loosing it's grip at depth.

Surface Water Temps: The more warm water in the equatorial East Pacific means more storm production in the North Pacific during winter months (roughly speaking). Cold water in that area has a dampening effect. Regardless of what the atmospheric models and surface winds suggest, actual water temperatures are a ground-truth indicator of what is occurring in the ocean. All data is from blended infrared and microwave sensors.
Satellite Imagery
Hi-res Nino1.2 & 3.4: (12/16) The latest images (1.2 3.4) indicate a very thin and repressed cool pool of water along the immediate coast of Peru but it is contained there migrating nowhere and if anything getting smaller. Warm water is developing solidly just off the coast there and reaching up into Ecuador and the Galapagos. A cool bubble previously between Costa Rica to the Galapagos is retreating fast and loosing identity. The standard thin cool stream continued from just west of the Galapagos out to 120W, much smaller in coverage than weeks past. A broader area of cool temperatures remains from 120W westward to 160W but appears to be fading. La Nina is loosing some control of surface waters of the East Pacific and holding in the Central Pacific suggesting the a westward di.cgiaced La Nina is remains in control.
Hi-res 7 day Trend (12/16): A warming trend continues along Chile and Peru but is fading some off Ecuador. Warming generally holds out to 110W with maybe one cool pocket embedded there. West of there a neutral trend was exhibited with pockets of warming and cooling waters present and a little stronger than in weeks past. The cool pattern in the Central Pacific is nowhere near as prominent as weeks and months previous and is weakening strongly in the East.  
Hi-res Overview:
(12/16) A La Nina cool pool is present over the equator from the Galapagos west to 170E and broadest south of Hawaii. La Nina is holding coverage in the west and loosing coverage in the east.
Nino1.2 Daily CDAS Index Temps: (12/17) Today's temps are falling at +0.224.  
Nino 3.4 Daily CDAS Index Temps: Today (12/17) temps were steady down at -0.476 coming off a recent peak at +0.15 on 12/6. Temps are oscillating warm to cool and back in 2-3 week cycles within a range from -0.3 to -1.0 degs.

Click for Full Sized Image

CFSV2 Forecast for Nino3.4 SST Anomalies



SST Anomaly Projections
CFSv2 Uncorrected Data (12/17) This model suggests La Nina developed from June thru Oct in the -0.55 deg range then started rising to -0.5 on Nov 1 and up to 0.2 degs on Dec 1. The forecast has temps gently rising to -0.1 degs on Jan 1, neutral on mid-Feb, then slowly rising from there to +0.2 degs in July, steady out till Sept. This indicates that La Nina is effectively over and a return to normal temps is expected in Spring.
IRI Consensus Plume: The mid-Nov Plume depicts temps have reached their peak minimum at -0.6. A slow increase in temps is forecast thereafter to -0.4 in Jan 2017 and neutral in April, starting to turn weakly positive after that to +0.1 in June. This is consistent with last months forecast and barely in La Nina territory. See chart here - link. 

Atmospheric Deco.cgiing (Indicating the presence of El Nino in the atmosphere driven by the ocean):
Southern Oscillation Index (12/17): The daily index was rising some today at 0.88 coming off a 7 day mostly negative run. The 30 day average was rising to +1.12. This suggests the Inactive Phase of the MJO has been in control recently driving the SOI upwards. The 90 day average was falling at +0.47. La Nina is trying to hang on, but loosing ground.
ESPI (like SOI but based on satellite confirmed precipitation. Positive is good, negative bad): (12/17) Today's value was falling more at  -1.32. A peak low was reached on 11/2 at -1.94 the deepest it had been so far in this event suggesting La Nina was getting better established. But that is changing, with it trending generally upwards (a better direction) and suggesting La Nina is fading.
Pacific Decadal Oscillation: The PDO continues positive, though much weaker lately (as expected with La Nina setting in).
Per NOAAs index recent values (Jan-Oct) are: +0.79, +1.23, +1.55, +1.59, +1.42, +0.76, +0.12 then falling to -0.90, -1.09 and -0.88 in Oct. But in Nov, it was up to +0.53
The Washington EDU index (Jan-Oct) are: +1.53, +1.75, +2.40, +2.62, +2.35, +2.03, +1.25 +0.52, +0.45 and +0.56 in Oct. We're waiting for the Nov update.
The PDO turned from a 6 year negative run (2008-2013) in early 2014 and has been positive until Aug 2016, the result of a turn towards La Nina. Looking at the long term record, it is premature to conclude that we have in-fact turned from the negative phase (La Nina 'like') to the positive phase (El Nino 'like'), but the data suggests that could be a real possibility. We've been in the negative phase since 1998 through at least 2013 (15 years). By the time it is confirmed (4-5 years out), we will be well into it.

See imagery in the ENSO Powertool

****

External Reference Material: El Nino Southern Oscillation (ENSO), Madden Julian Oscillation (MJO), Pacific Decadal Oscillation (PDO), Southern Oscillation Index (SOI), Kelvin Wave

Add a STORMSURF Buoy Forecast to your Google Homepage. Click Here: Add to Google
Then open your Google homepage, hit 'edit' button (top right near graph), and select your location


Powerlinessurf Jeff Clark Inside Mavericks

Local Interest

Stormsurf Video Surf Forecast for the week starting Sunday (12/18): https://www.youtube.com/watch?v=unW5ghPgDh4&feature=youtu.be&hd=1
For automatic notification of forecast updates, subscribe to the Stormsurf001 YouTube channel - just click the 'Subscribe' button below the video.

Titans of Mavericks on HBO Sports with Bryant Gumbel https://www.youtube.com/watch?v=luQSYf5sKjQ

- - -

Click here to learn more about Casa Noble Tequila! Casa Noble Tequila If you are looking for an exquisite experience in fine tequila tasting, one we highly recommend, try Case Noble. Consistently rated the best tequila when compared to any other. Available at BevMo (in California). Read more here: http://www.casanoble.com/

Mavericks Invitational Pieces Featuring Stormsurf:
http://www.bloomberg.com/video/how-to-predict-the-best-surfing-waves-EsNiR~0xR5yXGOlOq2MqfA.html
http://www.cbsnews.com/videos/surfs-up-for-mavericks-invitational-in-calif/

Time Zone Converter By popular demand we've built and easy to use time convert that transposes GMT time to whatever time zone you are located. It's ion left hand column on every page on the site near the link to the swell calculator.

Read all the latest news and happenings on our News Page here

Surf Height-Swell Height Correlation Table

750

.
Contact | About | Disclaimer | Privacy
Advertise/Content | Links
Visit Mark Sponsler on Facebook Visit Stormsurf on Instagram Visit Stormsurf on YouTube
Copyright © 2018 STORMSURF - All Rights Reserved
This page cannot be duplicated, reused or framed in another window without express written permission.
But links are always welcome.
Buoys | Buoy Forecast | Models: Wave - Weather - Surf - Altimetry - Snow | Pacific Forecast | QuikCAST | El Nino | Tutorials | Great Circles | Calculator