The best times to visit Porthmadog for ideal weather are
June 18th to September 9th
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
Porthmadog Travel Guide
Other Porthmadog Travel Info
Weather in Porthmadog
Average temperatures in Porthmadog vary somewhat. Considering humidity, temperatures feel cold for most of the year with a chance of rain or snow throughout most of the year. The area is less temperate than some — in the 13th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Porthmadog, the hottest months are July, August, and then June. See average monthly temperatures below. The warmest time of year is generally late July where highs are regularly around 65.3°F (18.5°C) with temperatures rarely dropping below 52.3°F (11.3°C) at night.
Porthmadog Temperatures (Fahrenheit)
Porthmadog Temperatures (Celsius)
The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.
Porthmadog Perceived Temperature (F)
Porthmadog Perceived Temperature (C)
Average Porthmadog Temperatures by Month
Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.
|Month||Avg. High (°F)||Avg. Mean (°F)||Avg. Low (°F)|
|Month||Avg. High (°C)||Avg. Mean (°C)||Avg. Low (°C)|
Precipitation (Rain or Snow)
If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Porthmadog are June, April, and then March. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around mid April. For example, on the week of April 16th there is 1 day of precipitation on average. By contrast, it’s most likely to rain or snow in early December with an average of 5 days of significant precipitation the week of December 3rd.
When can you find snow in Porthmadog? Weather stations report no annual snow. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.
Chance of Precipitation
The graph below shows the % chance of rainy and snowy days in Porthmadog.
Snow on the Ground
The graph below shows the average snow on the ground in Porthmadog (in).
Average Rain and Snow by Month
|Month||Daily Chance of Rain||Average Snow Depth (in)||Total Precipitation (in)|
|Month||Daily Chance of Rain||Average Snow Depth (cm)||Total Precipitation (cm)|
Humidity and Wind
Porthmadog has some very humid months, and high humidity throughout the year. The least humid month is May (71.4% relative humidity), and the most humid month is October (80.4%).
Wind in Porthmadog is usually stronger than many places. The windiest month is January, followed by December and November. January’s average wind speed of around 16 knots (18.4 MPH or 29.6 KPH) is considered “a moderate breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in early December where average top sustained speeds reach 28.1 knots, which is considered high wind or moderate gale winds.
Relative Humidity (%)
The graph below shows the average % humidity by month in Porthmadog.
The graph below shows wind speed (max and average) in knots.
Average Wind Speeds
Show Wind Speeds
All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.
|Month||Avg. Wind||Avg. Wind Feel||Sustained High Wind||High Wind Feel|
|Jan||16||Significant breeze||25.7||Very strong breeze|
|Feb||12.8||Significant breeze||21.4||Strong breeze|
|Mar||13||Significant breeze||21.8||Very strong breeze|
|Apr||11.3||Significant breeze||19.2||Strong breeze|
|May||12.9||Significant breeze||21||Very strong breeze|
|Jun||10.7||Gentle breeze||18.1||Strong breeze|
|Jul||11.2||Significant breeze||19.1||Very strong breeze|
|Aug||12||Significant breeze||19.6||Strong breeze|
|Sep||10.9||Gentle breeze||18.4||Very strong breeze|
|Oct||12.9||Significant breeze||21.7||Strong breeze|
|Nov||14.1||Significant breeze||23.5||Very strong breeze|
|Dec||15.9||Significant breeze||26.1||Very strong breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to Porthmadog?
Our best data indicates this area is somewhat safe. As of Oct 07, 2019 there are travel warnings for the United Kingdom; exercise a high degree of caution. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Sep 06, 2019.
The Busiest and Least Crowded Months
The busiest month for tourism in Porthmadog, the United Kingdom is January, followed by June and July. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Porthmadog in December. Those willing to visit at these times will likely find it the least expensive month.
Estimated Tourism by Month
Most Popular Months to Visit
Overall Porthmadog Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderately cold. Highs range from 61.1°F (16.2°C) and 46°F (7.8°C) with warmer temperatures in the later months. Rain is very common with 10 to 12 days of significant precipitation per month. Spring is the slowest for tourism, which makes it a good time for those looking for deals.
Summer (June through August)
The middle-year months have comfortably cool weather with high temperatures that are brisk. These months see moderate precipitation with 9 to 16 days of precipitation per month. June – August is the busiest season for tourism in Porthmadog, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 61.7°F (16.5°C) and 45.9°F (7.7°C), which will feel chilly given the humidity and wind. It rains or snows a great amount: 11 to 18 days per month. Tourism is fairly slow during these months due to the weather, so hotels may be lower priced.
Winter (December through February)
Weather is too cold this time of year in Porthmadog to be enjoyable for warm weather travelers. The average high during this season is between 46.6°F (8.1°C) and 42.3°F (5.7°C). On average, it rains or snows a very great amount: 12 to 19 times per month. These times of year are the second busiest with tourists.
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