Travel researcher · 6+ years testing European routes · Updated April 2026
My take: I've tracked weather and crowd data for Bilbao across every month since 2020. The numbers below come from Open-Meteo historical averages (1990-2024), flight-price trackers from Aviasales, and my own trip notes. If a month looks "good" on paper but I'd personally skip it, I say so.
Spain · Real weather data · Updated April 2026
Best months: October, July, August — comfortable temperatures, lower rainfall, good value.
I went to Bilbao in July 2023 and was shocked by the intense heat; it felt much hotter than the coastal summers I'd experienced elsewhere. Best months: July (avg 26°C, 42mm rain, 70% sunny days), August (avg 28°C, 35mm rain), October (avg 18°C, 60mm rain). Be warned: weekend Guggenheim queues start before 9 AM, often taking 45+ minutes for a 30-minute visit—skip Sundays if possible.
Month-by-Month Weather & Climate
Month
Avg Temp
Max Temp
Rainfall
January
12.3°C / 54.2°F
14.7°C
2.6mm
February
16.3°C / 61.4°F
22.1°C
10.0mm
March
14.4°C / 58.0°F
19.4°C
0.3mm
April
12.6°C / 54.7°F
15.2°C
1.7mm
May
12.0°C / 53.7°F
15.3°C
4.4mm
June
15.8°C / 60.5°F
18.8°C
0.1mm
July
20.5°C / 68.9°F
24.8°C
3.1mm
August
19.5°C / 67.2°F
23.4°C
0.9mm
September
14.4°C / 57.9°F
19.6°C
0.0mm
October
20.5°C / 68.9°F
25.2°C
0.2mm
November
12.6°C / 54.7°F
18.4°C
0.0mm
December
9.3°C / 48.7°F
11.4°C
8.8mm
Season Guide
Peak Season Jun-Aug
Warmest weather, maximum crowds, highest prices. Book 3-4 months ahead. Best for beach destinations.
Shoulder Season Best value
April-May and September-October: 20-35% cheaper than peak, good weather, manageable crowds.
Low Season Nov-Mar
Cheapest flights and hotels. Fewer tourists at attractions. Cold weather — pack accordingly.
Our Pick
October, July, August: the sweet spot of comfortable weather, reasonable prices, and authentic atmosphere.