Murcia, where it is

Murcia, the capital of the Autonomous Community of the same name, is located in the plains, about 35 km (20 mi) away from the coast, in south-eastern Spain, and has a climate that can be defined as almost Mediterranean, having a particularly remarkable aridity and a very hot summer, and a good amount of sunshine even in winter.
The average temperature of January is 10.5 °C (51 °F), that of August is 27.5 °C (81.5 °F). In winter there are several mild periods, while occasionally there can be cold periods, with highs around 10 °C (50 °F) and light frosts at night. In summer, especially in July and August, the temperature can reach 38/40 °C (100/104 °F).
Here are the average temperatures.
Murcia - Average temperatures
Min (°C)5681013182021181496
Max (°C)171821232731343431262017
Min (°F)414346505564687064574843
Max (°F)636470738188939388796863

The rains are scarce, only 300 millimetres (12 inches) per year; in particular the winter is drier than it normally is in Mediterranean climates; in summer it almost never rains. Due to the scarcity of rainfall, the landscape is arid. Rainy days are particularly rare, although when it rains, sometimes it can rain a lot.
In the city, basically it never snows, while sometimes it can snow in the higher areas of the province.
Here is the average precipitation.
Murcia - Average precipitation

The amount of sunshine in Murcia is great in summer, when clear skies prevail; even in winter, however, there are several sunny days.
Murcia - Sunshine

Murcia, Cathedral

Costa Cálida

On the coast of the province of Murcia, called Costa Cálida, the temperatures are typical of the Mediterranean coasts, and therefore summer is not as hot as in the capital and in the flat inland areas of the province, although it is more humid (but fortunately with the breeze from the sea), while in winter, very cold temperatures at night are even more rare: typically they only drop to 0 °C (32 °F) in the coldest nights. The rains, however, remain scarce, around 300 millimetres (12 inches) per year, and there's a good amount of sunshine even in winter. Although it is an arid area, on occasion the coast of the province of Murcia may be affected by heavy rains, which can lead to flooding.
Along the coast, like in Murcia, it practically never snows. On the 27th of January 2005, after 60 years, it snowed in Cape Palos, a place more exposed to the north wind than the rest of the coast.
Along the coast we find towns such as Cartagena, San Pedro del Pinatar, Santiago de la Ribera, Águilas, Los Alcázares, Mazarrón. There are tourist resort with golf courses, bays and natural harbors, islands and beaches where you can surf; there is also a large lagoon, called Mar Menor, separated from the sea by a strip of sand (called la Manga); inside the lagoon there are five small islands.
In the southern part of the coast, we find the natural park of Sierra de la Muela, Cabo Tiñoso y Roldán.

Manga del Mar Menor

Here are for example the average temperatures of San Javier, where the average of January is 11 °C (52 °F), that of August is 25.5 °C (78 °F).
San Javier - Average temperatures
Min (°C)67810141821221915107
Max (°C)161719202326293028242017
Min (°F)434546505764707266595045
Max (°F)616366687379848682756863

In San Javier, only 310 mm (12.2 in) of rain fall per year; here also you can notice the low number of rainy days. Here is the average precipitation.
San Javier - Average precipitation

The sea in the Costa Cálida is warm enough for swimming from July to September, when it reaches 23/25 °C (73/77 °F); it remains cool until June. Here, for example, the temperature of the sea at Cartagena.
Cartagena - Sea temperature
Temp (°C)151415161821232524211816
Temp (°F)595759616470737775706461

When to go

The best time for a beach holiday in the Costa Cálida is the summer, from June to August. For swimming, the best time is from July to September, although by September, which overall is still a good month (especially in the first half), the first Atlantic disturbances begin to occur. May and June are sunny months, but the sea is still a bit cool, especially in May, when it is actually a bit cold.
Even though good weather is not always guaranteed, spring and autumn are ideal for visiting the city of Murcia and for excursions to the other cities of the interior (see Lorca), given that the summer can be very hot.