what it the temperature here like?
The surface heat flow anomaly around the Hawaiian Swell is only of the order of 10 mW/m.
Hawaii hotspot

The surface heat flow anomaly around the Hawaiian Swell is only of the order of 10 mW/m, far less than the continental United States range of 25 to 150 mW/m. This is unexpected for the classic model of a hot, buoyant plume in the mantle. However, it has been shown that other plumes display highly variable surface heat fluxes and that this variability may be due to variable hydrothermal fluid flow in the Earth's crust above the hotspots. This fluid flow advectively removes heat from the crust, and the measured conductive heat flow is therefore lower than the true total surface heat flux. The low heat across the Hawaiian Swell indicates that it is not supported by a buoyant crust or upper lithosphere, but is rather propped up by the upwelling hot (and therefore less-dense) mantle plume that causes the surface to rise through a mechanism known as "dynamic topography".
where did the magma that erupts from mauna loa likely form The volcano's magma comes from the Hawaii hotspot. where is mauna loa? Hawai, U.S. state. what is it? It is one of five volcanoes that form the Island of Hawaii. does anyone monitor this place? Hawaiian Volcano Observatory and Mauna Loa Observatory. what is the above stated hotspot? The Hawai’i hotspot is a volcanic hotspot located near the namesake Hawaiian Islands. is there any theory related tho this? Canadian geophysicist J. Tuzo Wilson proposed the hotspot theory to explain these zones of volcanism so far from regular conditions, a theory that has since come into wide acceptance. how frequently does it erupt? Over the last six million years they have been far higher than ever before, at over per year. how did it evolve? It is built from five separate shield volcanoes that erupted somewhat sequentially, one overlapping the other.
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Hawaii hotspot [SEP] Temperature
Indirect studies found that the magma chamber is located about underground, which matches the estimated depth of the Cretaceous Period rock in the oceanic lithosphere; this may indicate that the lithosphere acts as a lid on melting by arresting the magma's ascent. The magma's original temperature was found in two ways, by testing garnet's melting point in lava and by adjusting the lava for olivine deterioration. Both USGS tests seem to confirm the temperature at about ; in comparison, the estimated temperature for mid-ocean ridge basalt is about . The surface heat flow anomaly around the Hawaiian Swell is only of the order of 10 mW/m, far less than the continental United States range of 25 to 150 mW/m.